Andrew Massie's Blog

2012 - Moving forward?

2012-01-11T12:44:00.010+13:00

Well, a new year is upon us. Mayans? Nah!

Things that have happened since the last post (not in any particular order):

23rd December 2011 a Magnitude 6 earthquake occurred in the Christchurch area, initiating a swarm of quakes offshore, prompting tsunami concerns and the GNS to report the aftershocks could go on for decades. Being only 3km from the epicentre, our house received further damage, as well as thousands more. The quake was extremely violent and knocked my wife off her feet even though she was bracing herself in a doorway. Scary stuff.

The 23rd December earthquake swarm courtesy GNS

Red Zones have been announced around Canterbury, in which property owners have been offered 2007 Rateable Value prices for their properties by CERA (Canterbury Earthquake Recovery Authority), a New Zealand Government Department established due to the quakes with Roger Sutton as CEO. Our own property was declared blue/green zone, which means we could rebuild, but with a stronger foundation and after a geotech report on our property's viability in future earthquakes has been compiled by a geologist. Mainzeal, our insurance companies' main contractor is apparently 'waiting for the earthquakes to stop', before commencing rebuilding.

A sunken house in Bexley

I have given two presentations on my experiences during my Academic Study Leave (ASL), one to a joint CPIT/Canterbury Electrical Association, and one to the Canterbury Electrical Association's AGM.

I was generously invited to co-write an academic paper on 'The impact of the Christchurch earthquakes on the electrical power system infrastructure' by Professor Neville Watson from Canterbury University for the New Zealand Society for Earthquake Engineers quarterly journal. This paper was accepted for publication in December.

Professor Watson also introduced me to Professor Venayagamoorthy from The Missouri University of Science and Technology, who is a worldwide leading authority on 'Smart power networks'. I gave both Professors a tour of our Sullivan Ave campus. CPIT and I have given both Professors authority to use my ASL photos in their very valuable work. In December, Professor Watson gave me a tour of the Canterbury University Electrical Engineering department, which was fantastic!

Professor Venayagamoorthy and me at the CPIT Tradefit site

I applied to have my ASL work classed as research at CPIT under the title 'Learning Cable Jointing and Line Mechanic work during the Canterbury earthquakes', asking the question; "What are the educational benefits of collecting and analyzing multimedia evidence of workplace skills to inform the development of new courses?". As part of this I have submitted an abstract with a view to presenting at the New Zealand Vocational Education and Training (VET) Research Forum in Wellington in April.

I attended the 2011 ESITO annual Lines Competition and Awards dinner at Mystery Creek in Hamilton with my Manager, Stephen Price.

ESITO Lines Comp Lineys going hard

My wife and I visited Geonet in Lower Hutt in November where we were given a fantastic tour by Sara, author of the 'Shaken not Stirred' blog.

Me at Geonet

Geonet reception wall - flash gear!

The famous Sara from Geonet!

I completed the Diploma in Tertiary Learning and Teaching 604 course 'Applied Learning Project', based on my ASL experience and written conclusions. Thanks Selena!

My wife and I attended a Connetics 'thank you dinner' at the RNZAF Air Force Museum in Christchurch we were generously invited to. It was a fantastic night dining amongst the fantastic aircraft in superb company for a superb company!

A4K Skyhawk at the RNZAF Museum, Christchurch.

I gained promotion from 'Academic Staff Member' to 'Senior Academic Staff Member' at CPIT although one of my colleagues, who I thought would get promoted ahead of myself did not, which I was very confused and disappointed about.

So a lot of water has passed under the bridge. Poor Christchurch (and Canterbury) have been nailed again by yet another major earthquake with yet more damage, but thanks to power network reinforcing, there were few outages. The Rawhiti Substation, which replaced the sunken New Brighton substation is open now. The power reliability has been good. Not perfect, but good, which is good(?) considering the current environment.

Rawhiti Substation (now complete)

CPIT for the rest of 2011 was 'flat stick'. Due to contractual negotiations being difficult, one of the CPIT unions engaged random strike action, which made life difficult, as all staff and students were stressed (as well as the rest of Canterbury) and emotion was high.

I have so far received no 'green light' to start development of Cable Jointing or Line Mechanic courses, however, I have been doing work on this in my own time. CPIT are in the process of employing two more staff into our department, which will hopefully help to ease the load. Unfortunately no Cable Jointers or Line Mechanics have applied for these jobs, as they seem reluctant to apply for jobs in the academic profession, as they have also done for the last 6 years, which is a shame.

In 2012 I am continuing to teach CTC (Canterbury Tertiary College) and 'Youth Guarantees' students. My Manager tells me it will be an unbelievably busy year. We have our normal courses, CTC, Youth Guarantees, and also special Maori and Pacific Island electrical students to teach this year.

My Manager also instructed me to take all my leave now, as time off during the year will not be allowed, so I'm having a big holiday now, but with no more until December 2012, which is a shame, as my wife Emma can't take any as leave her work is so busy at the moment.

I hope everybody who reads this has a prosperous 2012, and fingers crossed for Canterbury that the quakes stop and the rebuild hopefully begins soon. It has to sometime!

Finally, here's a tribute video to the Christchurch power workers I made:

Cheers, Andrew

Christmas decorated chemical toilet disposal container in Dallington. YES people are still using them!

'Thank you's..

2011-07-20T00:17:00.000+12:00

I've settled back in at CPIT and getting back in the run of things at the Trades Innovation Institute. I'm getting used to being back now, and finally accepting my ASL is over and had time to reflect on it..

Into it on the 8th March

I'm looking back now and realizing just how amazingly lucky I was, having started this on the 31st January this year (wondering if I was going to see quake damage from September!), and what we've been through here in Christchurch. Not only have I gained a massive amount of experience in Cable Jointing and Line Mechanic work, I've also gained 20Gb of photos and video of the aforementioned work as teaching resources, earthquake damage, and really, captured a part of our history from a 'trades academic' point of view. I feel extremely lucky and privileged to have worked with some of the most heroic individuals I have ever met, who have showed grit and determination in their various tasks to fix the quake-damaged Christchurch distribution network.

The quakes are tapering off (at this stage), and geologists' statistical forecast is looking promising for less quakes and (hopefully) maybe no more M6+ quakes. It's great news, trust me!

I want to make this post about thanking the awesome individuals who helped me at Connetics and other companies too. This has been the greatest work experience of my life, and I hugely appreciate the way that the following people went out of their way for me, instructed, instructed, tolerated and taunted me!

Firstly; Phil Duns, the Connetics Underground Manager. Phil was instrumental in helping me at every turn, and even 'went in to bat for me' when things didn't go to plan. Phil, you're an inspiration, and I hope to repay your kindness eventually.

I'd like to thank the following also from Connetics' Management;
Jono Brent, the CEO who showed awesome leadership during what was clearly a difficult time. John Goodenough, for the general assistance and the 'open office'! Sandy, Wendy, Louisa, Diane, and the Pete Johnson. Thank you all for your help.

Jono and John 'rallying the troops', March 7.

The Cable Jointers:
Steven Bright, thank you so much for the help, instruction, and fun! Robbie Hill, the same! I had a blast with you guys, and I'm forever corrupted!

Steve and Robbie after Steve dinged a big digger.. kidding!

John Hyland; Thanks for telling me about the unusual work! The 'John Hyland system' of using a bike jack is being patented as we speak!

John 'texting' the joint closed.. He has a new brand of arcproof overalls on in this pic..!

Reece, thank you for the instruction and taking photos of me working!

Barry; thank you for letting me know the best jobs to go to, and for sending me off early on the 22nd February. You quite possibly indirectly saved my wife's life.

Karl, Wayne, Ivor, CJ, Scannel, Rex, Ted, Dennis, Terry (the Joint Guru!), Andy, Jeff, Jamie (the famous guy!), and Skid, thanks for all the help and fun guys!

CJ and Scannel flying the flag

Jamie's 'spiking face' and Steve's 'Cheesy grin'.

Ted and Rex ignore the nice view and got down to work..

And our Northland and Auckland mates; Jamie (ma hun!), Clinton, Whari, and Garfield; You and your brothers from the North were our saviours. Thank you, you're awesome. Chur, Bros!

Whari and Alby from Northpower.. That's how we roll!

T and Peachy from Transfield; thank for the laughs!

Thanks also Barry and Conrad from Top Energy, too.

Line Mechanics:
Firstly I want to thank my mate (and brother!) Awesome Peter Boyce.. Thanks for the instruction and help (pre-loaded tool use), fella!
Also Carl (the Chopper King!), Nik, Anton, Danny, Simon (the genius), Hard-case Tim(!), Roger, Ken, Murph, Bevan, James, Jason, Steve and Blair. Thanks all you guys!

Carl surveys the battlefield from his HV tank turret.

Ken is awesome! (Sorry, Pete, but he is too!)

Simon uses his tongue to measure a cable

Test Room:
Jacko, Nigel, Chris, Clive, Steve, Steve Duggan, Nick. Thank you.

I also want to thank Big Jase (Super-tough man-shorts) and Mark the STMS guys, Dave, Dean (BIG is good!), and Rodney (fellow chemical loo fan!) from underground too.

Jase the STMS (Super tough man-shorts) and Tim wearing his helmet!

'Big is good' Dean and Terry 'the jointing guru' spot a UFO.

I would like to thank CPIT for the opportunity to do this ASL also. I will do my utmost to help run courses in Cable Jointing and Line Mechanic work in the future, to train new blood and help fix our broken city.

Finally I want to thank YOU, the reader! I'm over 2000 hits now, and I'm honestly surprised how popular this blog is..! I'll continue to run this, I'm 'in the zone' now, and want to keep contributing to record the recovery of Christchurch.. keep watching!

Cheers

Andrew ;D

...... the story DOES NOT end here.....

Weeks 21 and 22 - final weeks of my ASL.

2011-07-13T00:55:00.001+12:00

Well, I'm back at CPIT now, and it's been a week of many emotions.. Even though I know I'm a Tutor who is now teaching the future electrical workers who will help rebuild Christchurch, I feel I've abandoned my city. Packing a shovel and digging, helping with joints, even talking to locals with broken homes, I felt like I was helping defy these earthquakes that have progressively worsened or ruined life for many of us.

What I don't miss; seeing damage. The central city and towards the east just has so much damage. Seeing all of this gets me down, really. I get this feeling of 'where do you start'? The job of fixing Christchurch seems massive. It will be a long process.

I want to thank so many people for helping me with my Academic Study Leave, what I will do is a new post (next time) and do it then. This post will cover my last two weeks with Connetics.

Soooooo....

Work log:

Monday 20th June: 11kV PILCA-XLPE-PILCA transition joints outside AMI stadium with Steve, Ivor, Dennis and CJ.

The cable joint hole.. took a long time to pump out!

Starting the joint

Tuesday 21st June: Reconnect pole, Lincoln.

The pole in Lincoln to be reconnected

Wednesday 22nd June: Disconnect overhead lines for insulation test, Moncks Spur, and straighten pole, Kingsford St, Dallington.

Danny attaching earths to 11kV cables on Monck's Spur

Poles on Kingsford St, Dallington.

Thursday 23rd June: Pages Road reattach barge board, Sumner 11kV overhead repair using helicopter.

Love this photo.. the boys about to earth the 11kV circuit.

The helicopter about to lift Carl

Carl working hanging from the helicopter

Friday 24th June: Straighten pole Locksley Ave, light pole New Brighton Road, and pole on Avonside Drive.

Leaning pole at Locksley Ave

Monday 27th June: Install disconnect in 11kV overhead conductors, Birch's Rd, Lincoln.

Ken and Bevan installing a line break

Finished line break

Tuesday 28th June: Grays Road, Chch Airport, install 33kV copper conductors.

Wednesday 29th and Thursday 30th June: 66kV underground-overhead pole connection, Islington substation.

Sealed against the weather; a 66kV pole having underground-overhead terminations done.

Barry and Terry preparing the 66kV cable for terminating

Friday 1 July: Red Zone: cut and sleeve 11kV PILCA, Gloucester and Colombo Sts.

Robbie and I sleeving off the 11kV PILCA

Steve isolating the cable

Me in front of the destroyed Christ Church Cathedral

Further analysis to come. Now my Academic Study Leave is over, I'm in a 'holding pattern' waiting for the green light to start developing courses for Cable Jointers and Line Mechanics. In the meantime, I'm back in my old role of teaching electricians, students that struggle at high school, and pre-trade electrical theory to current high school students. Next week, thank-yous.

Analysis; Damage to a power network from multiple major earthquakes.

2011-06-27T09:16:00.001+12:00

Christchurch has had 3 major, 10 moderate, and around 7000 minor earthquakes and aftershocks at this point in time. The following is a personal account of the damage based on my personal experiences and the different side-effects of earthquakes.

I need to stress at this point in time, I am NO geologist, seismologist, or network analyst. So some of this information may not be accurate, it's simply based on my logic as an Electrical Tutor! I apologize in advance if I say anything incorrect, and feel free to post anonymous comments (this has been done, already, thank you!) and correct me.

In my opinion there have been four major side-effects of a quake (in Christchurch's case):

Ground shaking
Liquefaction
Lateral spread
Landslides/building collapse/rockfalls.

Christchurch did not experience tsunami related to our own quakes at any stage. I will cover each category for some systems in the Christchurch distribution network that were affected, namely:

Substations
Overhead lines
Underground cables

Substations:

Ground shaking:
Large cast-iron circuit breakers and large transformers were affected by the shaking. Nothing is exempt from the ground acceleration and the following effects occurred:

Masonry bolts were removed from the concrete foundations by the ground shaking, which affected both circuit breakers and transformers. Also on multiple occasions, oil-filled transformers 'tripped out' due to the 'sloshing' of the internal insulating oil, making the float
switches think the transformer had developed a leak, which causes outages. I am not aware of any circuit breakers 'tripping' due to ground shaking, but it is a possibility.

Seismic bracing behind circuit breakers at Bromley substation

Seismic bracing at Bromley substation

During the last two decades, Christchurch's Network owner invested a significant amount of money in seismic strengthening their 270 brick substations which resulted in few sustaining serious damage. See HERE for more information.

Liquefaction:
Christchurch is effectively built on an existing swamp, particularly the eastern areas. The worst-hit example of a substation affected by liquefaction was New Brighton substation, which is approximately 200m from the Avon River. Lateral spread and a high water table were factors here also.

New Brighton substation sunk due to liquefaction

The February magnitude 6.3 quake caused the New Brighton substation to sink approximately 2m into the ground, damaging incoming and outgoing power cables. It also filled the switch room with approximately 700mm deep silt and water. This had to be cleaned out comprehensively and the two 66kV transformers were replaced with a single 66kV transformer fed from a new overhead line.

There were several smaller substation buildings that also sank and 'went out of level', but most appeared to continue operating without issue.

Lateral spread:

New Brighton substation may have been affected by lateral spread, but evidence was sparse to indicate that. As with liquefaction, lateral spread would have affected any substations that were near the Avon River. I'm not sure if that actually occurred at any stage.

Landslide/building collapse/rockfalls:
Sumner substation was hit by a massive boulder and partially disabled by this. It was built below a cliff composed of volcanic rock, some brittle, some boulders. I'm no geologist, so I couldn't describe the type of rock the cliff face was composed of, but the boulder that hit the substation was substantial and did serious damage.

The boulder that destroyed Sumner substation

Inside Sumner substation

Overhead lines:

Ground shaking:
Having seen up to 2.2G of ground acceleration from the magnitude 6.3 quake of February 22nd, Christchurch has seen unprecedented shaking due to an earthquake. Thousands of poles were heavily affected by this shaking and a large number were affected, predominantly by being left on leans, pulling barge boards off houses, straining lines, and damaging pole fittings such as cross arms and insulators. Conductors swung to within arcing distances and proceeded to do so. Also the ground acceleration caused the shafts of insulators to be bent and ties to be broken.

Leaning poles due to a combination of shaking and liquefaction in Kingsley St.

Video of using a helicopter to repair broken ties on an 11kV circuit that was inaccessible due to rockfall hazard in Sumner:

Liquefaction:
Many poles were affected by liquefaction, some sinking straight down, some leaning due to liquefaction coming up underneath the pole.

Installed 3 weeks prior to the June 13 magnitude 6.3 quake, this pole was affected by liquefaction.

The same newly-installed pole.

Lateral spread:
Once again, many poles close to rivers were affected by this in a similar manner to liquefaction. Also, due to the lateral spread, the land sank, causing the water table to rise, which also caused poles to sink.

This building sank more than the pole did, ripping the termination bracket off the roof of the building.

Landslide/building collapse/rockfalls:
Poles above and below cliffs were affected by rockfalls and landsliding. Poles were hit by debris below, as well as their associated lines. This damaged poles by outright destroying the pole to breaking insulators and crossarms.

The Sumner boulder that fell on a pole.

The pole with the boulder on it.

Underground cables:

Ground shaking:
Two of the four types of dynamic force that travel underground during a large earthquake can be seen below.

A static description of waves is shown HERE.

As anybody can imagine, these massive forces can affect subterranean infrastructure systems, such as power cables, telecommunication cables, water pipes and waste pipes to name a few. In Christchurch all the aforementioned systems were affected by the quakes, power cables being in the firing line.

A minimum of four major 66kV underground cables were damaged, two beyond repair. The sheer ground acceleration ruptured the concrete the cables were embedded in in multiple locations, mostly where the liquefaction was at its worst. The other two cables had faults that were able to be repaired.

Partially completed 66kV XLPE repair joint

In the centre of the picture is a faulted 11kV PILCA cable, above is the concrete in which the one of the heavily damaged 66kV oil-filled cables can be partially seen.

3-in-a-row; three PILCA 11kV cables all bent and faulted.

Other cables were damaged also, approximately 800 underground cable faults occurred from the February quake. 11kV paper insulated lead covered armoured (PILCA) cables were bent into Z and S shapes, causing the insulation to fail on them. Other faults included previous faults pulling apart and terminations being removed from protective devices. Cables that transitioned up poles were bent by the pole swaying during the quake.

Liquefaction:
The makeup of the swampy soil in the eastern areas of Christchurch seemed to allow cables to be damaged as stated above, but the actual liquefaction process of water bubbling to the surface of soil did not affect cables as the shaking did. Liquefaction rather made travel impossible in some cases and created large potholes that vehicles fell into. The higher water table involved pumping out joint holes before work, which in some cases took hours.

An abandoned joint hole, this particular joint incomplete as several faults were found on the same cable.

Lateral spread:

Lateral spread caused cables to fault next to bridges that the cables passed under, and also caused joints to tear apart near rivers. Also cracks that appeared in land on hillside suburbs tore T-joints, other joints and terminations apart.

Originally straight; this <still functioning> LV XLPE cable has been bent by lateral spreading.

Steve from Connetics showing the bent cable.

An 11kV XLPE joint torn apart by lateral spread.

A LV joint torn apart by lateral spread.

Landslide/building collapse/rockfalls:

I'm not aware of any faults due to these effects, however I understand many kiosks were damaged by falling buildings in the Christchurch CBD 'Red Zone' and the Lyttelton town centre.

Solutions:

Substations:

The circuit breakers inside Bromley substation were reinforced with steel braces to prevent further shaking and destabilizing. New Brighton substation was relocated to Rawhiti Domain, where there was little liquefaction and lateral spread. Sumner substation, I'm not entirely sure, but I think it was bypassed.

Overhead lines:

Due to the ease of fault finding and maintenance, overhead lines were rapidly repaired. Severe unstable poles were immediately repaired, and ongoing pole straightening is continuing.

Underground cables:

Approximately 800 underground cable faults were repaired. Test Technicians and Cable jointers from all over New Zealand and Australia were employed to assist with the mammoth diagnosis and repair effort. Specialist 66kV jointers were bought in to repair oil-filled and XLPE insulated cables. The irreparable 66kV cables were replaced with temporary 66kV overhead lines, to keep the power supply running through winter until such time as a window of opportunity to replace the faulty cables exists.

See HERE for my blog post regarding the Bromley-Dallington 66kV overhead install.
See HERE for my blog post regarding the New Brighton-Rawhiti 66kV overhead install.

Weeks 19 & 20 - Prebbleton Sub and major quake #3.

2011-06-23T07:07:00.001+12:00

Another fortnight post unfortunately, sorry. Life has become busy since June 13th when we had our 3rd major earthquake. Classed as an aftershock of the Mag 7.1 quake of September 4 2010, this was a Mag 6.3 quake which struck at 2:20pm on June 13th. More damage and liquefaction occurred, and was violent where I was working with my Line crew in Akaroa. I will cover this quake in depth later.

Work log:

Tuesday 7th June:
Connect 11kV cables into kiosk for 4x 1MW emergency generators, QEII park.

The 4x 1MW diesel generators, QEII park

Wednesday 8th June:
Connect 11kV cables from 4x 1MW generators into 11kV network, QEII park.

'Tapped into' 11kV cable, QEII park generator supply.

Thursday 9th June:
Underground-overhead 33kV transition terminations, outside Prebbleton substation.

Me doing 33kV termination, Jeff on right.

Friday 10th June:
Underground-overhead transition terminations, outside Prebbleton substation.

The overhead guys connect the 33kV terminations from the underground cables to the overhead lines.

Monday 13th June:
11kV overhead circuit breaker oil replacement live line and M6.3 aftershock.

Oil replacement in overhead circuit breaker

Tuesday 14th June:
Post-quake network assessment before repair start.

One of the underground Managers digging silt out of New Brighton substation (again)

Wednesday 15th June:
Re-energize domestic dwelling in Sumner after boulder destroyed pole, replace pole Lyttelton after quake caused wall to collapse and destabilize pole.

Me in front of the boulder that landed on a power pole. The boulder won..

The pole under the boulder. The cliff behind shows where the boulder came from.

Replacement pole being installed in Lyttelton. The bucket is holding the lines up temporarily.

Thursday 16th June:
Replace pole, Ripon St, Lyttelton after collapsing wall destabilized pole.

Unstable pole due to quake-related wall collapse in Ripon St, Lyttelton.

Friday 17th June:
Multiple jobs: Straighten pole Breezes Rd and reterminate conductors, straighten pole and reterminate conductors, Burwood, reenergize dairy, South Brighton, replace broken crossarm Waltham Rd, disconnect link pole Redcliffs.

Broken crossarm due to falling bricks, Waltham Rd

Broken crossarm

Analysis: Cable Jointer and Line Mechanic procedures

Due to the electrical industry in general being highly regulated, all trades within the sector have regulations and procedures all with one overarching purpose in mind: SAFETY.

Electricity can be lethal, as can falling, cutting, burning, crushing, and a host of other hazards. But with correct procedure and accurate following of that procedure, safety can be well maintained.

Connetics follow a strict procedure of using safety sheets in conjunction with job permits. All employees (and observers) must read this hazard sheet and sign it to state they are aware of the hazards and will comply with the site hazard rules. There are also job sign on/sign off sheets as well. It is not unusual to sign several safety sheets for a job, one for the job permit holder and another for the Site Traffic Management Supervisor (STMS).

One side of a hazard sheet. It has been blurred to protect privacy and copyright.

All Connetics vehicles carry an on-board safety folder which pack the latest safety regulations (the SM-EI manual is one), and lists safety procedures for Connetics staff and Orion contractors.

Lines vehicles carry several documents; examples include (see below):

The Orion Standard Construction Drawing Set <(c) Orion>. This contains instruction as to how poles and structures shall be constructed for the Christchurch and Canterbury region.

And the Connetics Live Line Procedure Manual <(c) Connetics> . This contains in-house instructions of procedure that must be followed when doing live line work.

Cable jointers also have such a comprehensive set of procedural rules, called the 'Underground Manual', which must be adhered to. Each jointing kit also has comprehensive instructions inside that describe how to safely and correctly complete a cable joint.

Accuracy in both jobs is crucial. Faults and mistakes can be very costly and dangerous. The ability to follow written instruction and procedure is critical in the supply industry, and unfortunately, students must develop skills in literacy to be able to perform jobs successfully and safely.

Sorry for such a short post, I'm developing a post about damage to power networks next, which should be very interesting. As always, questions and comments are welcome.

A wee link here showing how digital media can be used successfully for assignments:
http://www.stuff.co.nz/technology/digital-living/5160793/Students-give-YouTube-assignment-an-A-pass

Week 18; The relocation of New Brighton substation to Rawhiti substation.

2011-06-09T01:27:00.004+12:00

This week I observed the finishing of the circuit which is an extension of the original 'emergency circuit' that Orion, Connetics, Independent Lines, and Mainpower constructed to enable relivening of the New Brighton Substation after it was sunk by liquefaction from the M6.3 aftershock of the 22nd February 2011.

The extension runs to a new substation in Rawhiti Domain in New Brighton, which did not (and in future, hopefully won't) get much liquefaction. See 'Analysis' for further information.

New Brighton substation - a door even I can reach!

Work log:

Monday 30th May: Install 66kV poles on Keyes Road.

Tuesday 31 May: Start running 66kV conductors, Baker St.

Wednesday 1 June: Run 66kV conductors from Baker St to Keyes Rd.

Thursday 2 June: JOINTING: Prebbleton substation installation.

Prebbleton substation

11 and 33kV cables underneath the Prebbleton substation

Friday 3 June: Run 66kV conductors into Rawhiti substation.

ANALYSIS: How to relocate a substation and its circuits

Footage of the quake itself

Footage of liquefaction

The 22 Feb aftershock damaged Christchurch city power (and general) infrastructure terribly. As shown earlier in this blog, not only were subterranean power cables damaged and torn apart, substations were damaged also, and some sunk. The most crucial substation was the New Brighton substation on Pages Road.

The sunken New Brighton substation

Orion, Christchurch's power distribution company, immediately swung into action to get the power back on in the Eastern suburbs due to cable failures and the afore-mentioned substation. The underground 66kV oil-filled cable that originally supplied New Brighton substation was broken, bent and sheared off in many locations, rendering it unrepairable.

Uppermost embedded in the concrete is a damaged section of the original 66kV oil-filled cable that supplied New Brighton substation. Fully exposed is a damaged 11kV PILCA cable.

Orion called on some of its contractors, Connetics and Mainpower in conjunction with Transpower's contractor, Transfield, to construct an overhead 66kV circuit from the Transpower Bromley substation (which itself received damage) to the sunken New Brighton substation. This line was constructed in two weeks. In a normal situation, it would take around 18 months to get resource consent and approval to construct this kind of circuit.

Circuit map of the 66kV installed in record time inside 2 weeks after Feb 22nd.

Whilst the circuit was being constructed, the substation itself had to have tonnes of silt removed from inside to allow use of it again, and the two 66kV-11kV transformers had to be replaced by a single undamaged transformer, which I understand was obtained from Ilam substation.

The dark mark shows the level the silt was up to inside the substation.

After several 11kV underground cable faults were repaired, New Brighton substation was able to be re-energized, providing power to much of the Eastern side of Christchurch, including my own house (unfortunately it was too late for the anemones, clams, corals, tubeworms, starfish, and the Mandarin fish in our saltwater tropical fish tank, but hey, we're alive, right?).

The decision was undertaken to move the location of the New Brighton substation to a location that was not so prone to liquefaction and lateral spread, and Rawhiti Domain was deemed to be suitable.

Immediately the decision was made, preparations for construction began at the new substation site. This is another project that is being achieved in record speed.

Work beginning on Rawhiti substation site

A closer look

Good public information. All residents affected were given letterbox drops.

Once the substation was almost ready, Connetics and Independent Line Services were again contracted to do 66kV overhead lines, this time extending the original Bromley-New Brighton circuit to Rawhiti substation.

Circuit map of the New Brighton substation - Rawhiti substation run.

Pole installation began on the 25th May. The Connetics crews I was working with were on the northern side of the Avon river, Independent Lines Services doing the southern side and the river crossing.

Unfortunately I contracted a Gastronomic Virus at the start, so I was unable to see the first poles installed down Baker Street. I did, however, take a series of photos showing before, during and after..

A common misconception expressed by the public I spoke to on many an occasion was over the poles 'not all being straight'. Several poles are 'strainers', which means they are set at an angle on purpose on the outside of a bend or turn. 'Breast blocks' and 'Heel blocks' are pieces of pole underground which are actually used to keep the pole set at the angle it's set at.

Diagram of how underground blocks work.

Baker St poles

Live lines being temporarily held aloft while the existing pole is replaced with a much bigger 66kV one.

The insulated temporary crossarm, with spring loaded 'rat traps' which can be released using insulated 'hot sticks'.

Reconnecting LV crossarm and insulators

The 66kV HV line being strung above the LV crossarm

The poles were all installed, and the conductors done by 'streets', Baker St the first day, Gresham St the second day, and Keyes Rd into the substation on the third day.

As with Dallington, insulators were placed on the LV circuits below where we were running the 66kV conductors, and the conductors were fed through rollers attached to the insulators.

All rollers in place

Blair feeding conductor through a roller

Tim showing his pulling power!

Me being creative.. a view from the cable drum rollers. Winches are holding the conductors from rolling out and contacting the ground.

'Pistol grips' were used at every 90 degree pole, which is the norm. This allows the conductor to be run 'street by street'.

A 90-degree turn pole.

The substation wasn't quite ready for us, but conductors were run into place on time into the substation for connection onto onsite insulators.

Substation technicians install equipment

The transformer cooling unit arriving

Transformer and cooling unit in place. The overhead cables connect from the left of this picture.

The final run.

Once again, I am left in awe of the commitment of the supply industry workers, flawless, methodical work being done with all safety procedures being observed to the letter. Once again I observed the Line Mechanic 'psychic' ability of knowing the procedure inside out and working as one with little communication. Observation linked to good training and a professional attitude seem to be the keys to this ability.

The three 66kV overhead circuits that have been constructed to help keep the power on in Christchurch due to the M6.3 quake 22 February.

Next week I will cover connecting up 4x 1 Megawatt generators at QEII for bolstering the Eastern network over the winter. As seen on Queens' Birthday Monday, our shaking hasn't stopped and keeping the power network going over this winter is going to be a real task for Orion and its industry partners.

A sign that was attached to one of the new 66kV poles on Baker St. you just can't please everybody!

Weeks 16 & 17.. Test room, Jointing and the New Brighton-Rawhiti overhead 66kV circuit

2011-06-01T01:08:00.006+12:00

Hello again!

Before I start, I want to pay a personal tribute to the workers from other parts of NZ and Australia who have helped repair our broken city. Here's an Orion link:

My personal perspective comes from the coalface with the guys.
These workers came from Northland to Southland, and Australia. They came with a real sense of 'wanting to help', and talking to them, they initially felt it wasn't so bad, having arrived at a reasonably undamaged airport and well-built Connetics home base.

That all changed for them when they started working on damaged cables in our Eastern suburbs, hill suburbs and in and around the 'Red Zone'.

Comments such as 'Munted is so right' and 'how can this happen to these kind of cables' were made to me. It soon dawned on the workers the enormity of our situation. As a consequence, their response became more focused and considerate. A public thanking them daily, thank you BBQs and being 'looked after' became the reward for these workers. They took an ownership of the job and some felt bad abandoning us when they finally left! The majority felt several aftershocks and were very happy to leave them behind, however!

They focused on doing work in the place of locals who were doing up to 80 hours and more per week, while some spent up to 12 weeks away from their own families. Camaraderie was abound, and I found that Cable Jointers are practically 'cut from the same cloth' everywhere! Being privileged to work with these guys and being invited to a farewell social night for them was fantastic for me, and I can't say enough about these fantastic people.

I want to thank all of these workers personally. Thank you for helping us back onto our feet power-wise. You are all LEGENDS and I personally won't forget what you sacrificed for us.

I've created an online album of photos of the contractors HERE.

Work log:

I would like to point out that I was directed by CPIT to discontinue in the Test Room on the 17th May and go back to doing Cable Jointing and Line Mechanic work. Unfortunately this has stalled further education in cable fault finding and overarching understanding. I do not anticipate working in Street Lighting as earlier stated as a consequence.

Monday 16th May:
Worked on Peterborough St with Chris from the Test Room to find a low-voltage underground fault. Also worked late on a underground faulty cable in South Brighton on a private premises.

Damaged Peterborough St house

Chris from the Test Room Insulation Tests the suspect cable

The boys dig for a faulty underground cable in South Brighton.

Tuesday 17th May:
Maces Road 11kV faulty cable Bromley Road, Isolate, Earth, Test, and Energize when repaired.

Priory Street 11kV faulty cable find fault using thumper.

A BIG multifunction tester used to find underground cable faults

Wednesday 18th May:
Back into Cable Jointing department (ordered to by the Boss) 11kV PILCA-XLPE-PILCA New Brighton Road

More quake-bent cables

A contractor removes the semiconductor layer using a file

A number of failed historical underground joints

Thursday 19th May:
11kV 'Trouser' joint PILCA-XLPE-PILCA Orari Street, Bexley.

'Trouser' joint underway

Boundary box neutral bar broken when cable was stretched by the quake

Friday 20th May:
LV Kiosk Terminations, Dalziel Place, then communications cable and 11kV joints, Nurses' Hostel next to Christchurch Hospital.

The gates at the Nurses' Hostel are removed

LV terminations in kiosk

Communications joint

Finished Communications joint

Monday 23rd May:
Keyes Road 11kV PILCA-XLPE transition joint with Reece

ANOTHER damaged 11kV armoured cable

Tuesday 24th May:
11kV PILCA-PILCA to isolate the Copthorne Durham so the Christchurch Casino could be energized, Red Zone.

Side entry to the condemned Copthorne Durham Hotel

Shearbolt for 2x PILCA cable kit

Finishing 11kV PILCA-PILCA joint

Wednesday and Thursday 25th and 26th May:
Sick leave with a Gastronomic virus.

Friday 27th May:
LINES DEPARTMENT: Install poles for the 66kV overhead from New Brighton Substation to Rawhiti Substation.

Installing 66kV pole

Midway pole replacement; big for small!

Analysis: Jointing XLPE; A personal perspective

I thought it would be a good idea to describe what it's like to join an 11kV XLPE cable. It's all fine and good to see pics and video, but what is it like to actually do?

I joined a cable in Bexley as part of a trouser joint (see Thurs 19 May in log) and asked myself what it felt like to somebody who has never done one. Here we go:

Each cable jointing kit comes with an instruction sheet. The conductor size and obviously joint type must be taken into consideration (transition, trouser, XLPE-PILCA, PILCA-PILCA etc.) before getting the kit and ensuring the correct kit is being used. There is no margin for error; each kit costs around $1500.

Safety procedures must be followed. The test room must find the fault, mark the fault, and then the diggers dig the access hole and expose the cable. The test room must identify, isolate and earth both ends of the cable, at which point the Jointers 'spike' the cable to ensure isolation (spiking uses a blank shell cartridge to drive a metal spike into the cable, which would cause protective devices to operate when the spike shorts out conductors.

Once spiked, the cable is cut and jointing can start. In the picture below, I've already taken the HDPE orange outer layer off and the inner MDPE black layer also. The HDPE being the outer layer is hard plastic and strips a lot more easily if heated up (electricians strike something similar when stripping cable when prewiring a house on a frosty morning), so the cable is marked to the right length, heat is applied, and the outer layer is removed using a reasonably thick blade knife. Inside that is a type of white plastic webbing which fills gaps and allows flexibility of the cable. This is removed also, using a very sharp knife. Care must be taken using the knives, firstly to cut away from yourself, and secondly not to damage any other parts of the cable.

Removing the webbing.. Ignore the rug, some nice person threw it into the street!

Once the white webbing is removed, the three individual cores are exposed, each having an outer layer of copper which is termed 'neutral screen', but is actually an earth. In NZ's Multiple Earthed Neutral (MEN) system, Neutral and Earth should be the same potential anyway.
The Earths are peeled back and taped with insulation tape to the outer of the cable to protect them and keep them out of the way.

Dark red stretchy tape (called mastick) is applied to the outer of the cable just behind the initial strip mark. Mastick chemically bonds to itself once it touches, so extreme care must be taken to 'get it right first time'. Once the cores are separated, a 'boot' is applied and shrunk down at the base of the individual cores.

Applying the boot

Shrinking the boot down

The product so far..

Using semiconductor layer stripper

The semiconductor layer is stripped back extremely carefully (Connetics specify the use of a special tool) and the XLPE is stripped back as well. Once again measurements must be exact.

Using semiconductor layer stripper

Making measurements

XLPE strip tool

Removing the semicomductor layer

Prepared. Note the 'boot' at the left edge of the picture.

A layer of 'void filler' is applied to ensure a water block layer between the semiconductor layer and the XLPE layer. Void filler is yellow and chemically bonds to itself just like mastick, so care must be taken.

Applying 'void filler'

Heatshrink is applied outside the void filler.

Shrinking down. Care must be taken to avoid burning the heatshrink. This will degrade the insulating properties of the joint.

Shrink applied

Once the heatshrink has been shrunk down, the termination can be done. At this point it is a good time to 'double check' that all shrink is on the right parts of the cables being joined (you can't thread it on once the terminations are done!). The test room is then bought back to establish that phasing is correct. Once established, the terminations (shear bolts) can be tightened up and sheared off using a battery impact driver.

Inserting conductors into shearbolts.

Shearing off bolts

'Void filler' is applied to the outside of the shear bolts. Once done, the thick heatshrink with the semiconductor outer and insulating inner can be shrunk on in place.

More void filler

The thick heatshrink

Shrinking down

Still shrinking down.. there's a real knack to this!

Shrunk!

A layer of conductive webbing is applied to the outside of the joint so far. This allows earth conductivity to be consistent on the outside of the joint itself.

Doing the webbing

Once the webbing is attached, the external earths can be attached. The PILCA side neutrals have been bonded in the lead wipe. The neutrals are connected using 3 brass shear bolts.

Connecting the 'neutrals' (earths)

Brass shear bolts

Doing up the shear bolts

Once the neutral shear bolts have been connected, they have individual insulating tape applied around the outside of them to protect the final outer heatshrink from any sharp edges. The final outer heatshrink is in two pieces, and have another sticky black strip that is used inside the overlap.

The first of the final outer heatshrink bits

And the second...

Shrinking is done from the middle out.

Finishing off. All parts must be shrunk down.

Done!

Once finished, the Test Room is notified and they then do continuity testing, insulation testing, and then liven if Orion requires it to be live. I want to thank Reece for taking the photos of me!

I have to apologize for the now-fortnightly posting; I have been flat stick; The earthquake appears to have put several cracks in our foundation, and our house is on a lean as a result. Preliminary assessment from EQC and our Insurance company indicate our house will have to be rebuilt, which is making life busy for my lovely Wife and I.

I have put more photos in my earthquake damage online album HERE.

The Town Hall steps.. munted. I stood here a year ago for my graduation. So sad.

Next time: More 66kV overhead lines!

Weeks 14 & 15 - Subs department - Brookside, Hororata, Greendale Substations, Test Room

2011-05-17T23:08:00.005+12:00

Well, I've finished with lines in the interim until later this month. In the meantime I'm going to be spending some time in 'Subs' and the 'Test room' Departments.

Work log:

Monday 2 May: SUBS; Brookside and Hororata Substations; repair design fault with approved manufacturer's rewire.

Brookside substation

Switchgear at Brookside substation

Hororata Substation. The windows broken in the 4 September 2010 quake have been covered with wood.

Tuesday 3 May: Wire control unit in workshop.

Wednesday 4 May: Greendale Substation; Move and permanently wire communications unit.

Greendale substation.. yes, it's practically on the fault line.

Control units inside the substation

Evidence of the explosion that occurred at the back of a circuit breaker during the M7.1 earthquake.

Substation yard gates... do they line up?!!

Thursday 5 May: TEST ROOM; Isolate and earth faulty 11kV cables, Opawa Rd bridge and near AMI stadium. Also reconnect 11kV supply cable, Cannon Hill Crescent.

Australian cable jointers helping fix our broken network

Uppermost cable is earthquake damaged steel and lead armoured 11kV HDPE cable. Lower is replacement XLPE.

Damaged 11kV PILCA cable marked pink for jointers

Friday: 6 May: Sheath test 66kV cable between Papanui and McFaddens Rd Substations. Find fault on Orchard Rd and Bridge St lighting circuits.

McFaddens Rd Substation 66kV transformer building

Nigel from the Test Room earthing a 66kV circuit prior to the sheath test

Monday 9th May: Red Zone 66kV sheath test and Bankside LV underground cable fault.

Inside the Red Zone near Victoria Square.. Which building is 'wrong'?

The same jointers (Shaun Baker and Barry Kelly) that got Dallington Substation reconnected repair the Addington-Armagh 66kV Oil-filled cable

The Armagh "inside" substation

Robbie and Steve dig for a low-voltage (LV) cable after the fault has been found with the 'thumper'.

Nigel replaces pole fuses

Tuesday 10th May: Find faulty 11kV cable between Beach Road substation and New Brighton substation using TDR and 'thumper'.

Connetics and Delta (Otago) vehicles at Beach Rd sub

The TDR (time domain reflectometer) in action

Peter from Delta using listening equipment for 'thumping'

Marking the faulty cable after 'thumping'

Wednesday 11th May: Red Zone test 11kV cable.

The CTV elevator shaft and stairwell is demolished.

A Madras St sub. Left is the gap where a church was.

Thursday 12th May: Ferry Road LV cable fault find and repair.

LV fault found using 'thumper'

Existing joint torn apart by earthquake.

Friday 13th May: Isolate/Test/Join/Test/Energize 11kV XLPE cable Shands Road.

Analysis: Subs and Test room departments

Subs are electrical fitters, which is the supply equivalent of industrial electricians, of which I am one. The work the subs workers do is very familiar to me and I felt quite at home in their workshop and on-job with them. However, the point of my ASL is not to be in my 'comfort zone', and to throw myself at the unfamiliar and learn it, so educationwise, it was, however, not hugely beneficial for me to spend too much time in subs, so I limited that to just three days.

The Test Room, however, is a whole new ballgame for me. The workers in the test room are the network 'fault finders', 'isolators', 'energizers', and almost direct the repair of the network. Faults in underground and overhead cables are found using complex pieces of equipment acting upon order sheets from network owner Orion.
There are two ways the Test Room operate; faults and scheduled maintenance.

Faults are identified by the network controller in the control room or rung in by the public. Orion will then use a Network Operator to identify the fault or faulty circuit. Often the supply to consumers can be maintained by 'ring circuits' or 'backfeeding'.
Once the faulty circuit is identified, the Operator will disconnect the circuit by operating circuit breakers or removing fuses or links.

The Orion 'Operating order' sheet

The job is then passed on to the Test Room for fault diagnosis and identification. The faulty cable is tested, and once the fault location identified, the cable is earthed.
This is where the picture becomes complete. A 'dig up' crew carefully exposes the faulty cable, cable jointers 'spike' the cable, and then repair the cable. The Test Room then test the cable once the jointers are clear, and if the cable is found to be without fault, the circuit is possibly re-energized, if Orion require it to be.

'Scheduled maintenance' is very similar, except a fault does not need to be found. Usually it involves a cable movement or connection change, once again involving the Cable Jointers.

My time in the Test Room completes a cycle of learning for me, I now have full understanding of the process involved in repairing a damaged cable. It would not be appropriate for me to endeavour into the very flash toys the Test Room employ to fault find cables with, as my focus at Connetics really is Cable Jointing and Line Mechanic work.

Analysis: Line Mechanic Vehicles

Line Mechanics have a large scope of work to cover; wooden poles, metal poles, reinforced concrete poles, and towers (pylons) must all be worked upon. A Line Mechanics' truck must be fully equipped for any eventuality as they sometimes work very far afield. There are two trucks used:

'HIAB' Truck

The 'HIAB' or 'crane' truck

The 'HIAB' truck is so named from one of the first models of transportable hydraulic crane trucks; Hydrauliska Industri AB, which is a Finnish manufacturer of loader cranes, demountable container handlers, forestry cranes, truck-mounted forklifts and tail lifts. See HERE.

The HIAB truck is predominantly used for pole handling and live line work. It's powerful yet compact when packed away crane is ideal for Line Mechanics' use. With plenty of cargo space on the back, and room for compartments in the side, it is a fully mobile workshop and crane.

A skilled crane operator can make a job far, far easier and less time consuming than a less experienced operator. Dual controls, one set either side of the rear of the truck enable ease of operation.

In addition to the hydraulic crane, there are hydraulic stability legs to prevent the truck capsizing under crane loads.

Another clever addition the HIAB truck has is a fully insulated 'line holder'. This device holds conductors up in the air when doing live line jobs as a temporary 'pole'.

The 'line holder'

The HIAB being the 'pole'

Tool and equipment compartments

Spare part compartments and even a jug and toastie maker!

Fuel and chainsaw

The deck

There are many other uses for a HIAB truck, these are just a simple overview.

'Bucket Truck' or 'Cherry Picker'

The 'Bucket truck' or 'cherry picker'

The 'bucket truck' is a vehicle primarily used for line mechanic access to poles and overhead network systems. It has a hydraulic telescoping arm, the last section being made of an insulating material for safety.

The bucket can legally be used as a work platform and line mechanics must wear harnesses (as when up poles as well) and be anchored inside the bucket as part of safe operating procedure. Dual controls, one set inside the bucket and one set on the truck deck allow for easy operation. Stability legs are also used on the bucket truck. Connetics bucket truck buckets are rated at 200kg total weight.

The 'bucket truck' tool compartments

'Going hard' on the 66kV Bromley-Dallington install in the buckets

Safety harness

It's a long way up; this is not a job for people with a fear of heights!

Between the two vehicles, the Line Mechanic must be competent in:

Driving a HT (Heavy trade) vehicle (licence required)
Operating a HIAB hydraulic crane (licence required)
Operating a bucket truck (licence required)
'Hot stick' or 'Glove and barrier' rating if working on live lines

I realise that my ASL, which was initially to gain experience in the supply industry in Cable Jointing and Line Mechanic work, has grown to actually being a recording of history. My Picasa account will have all my earthquake related photos. I'm more than happy to make them public. Institutions must make reference to CPIT if you choose to use them please.

I would like to extend a greeting to ETITO viewers, too, from the newsletter. Feel free to ask questions!

From Bedford Row, where I was when the M6.3 quake hit, with the Hotel Grand Chancellor leaning ominously behind.

Week 13 - Pole straightening, live line work, Bromley Substation

2011-05-04T02:19:00.004+12:00

Apologies, I'm a week late with this post.. I attended a conference at CPIT for Trades Innovation Institute staff. I presented with my colleague Rob Mattson at this conference and we were very well received.

Previous weeks' log:

Monday 18th April: Lift and repair liquefaction-sunken pole Netley Place, Aranui.

Pole lifted

Carl and James restraining cables

Tuesday 19th April: Live line switch pole replacement 11kV, Hoskyns Road, West Melton (see analysis).

Nik and Andre in action in full glove-and-barrier kit

Wednesday 20th April: Live line switch pole replacement 11kV, West Coast Road, SH73, Darfield (see analysis).

Lines being held temporarily whilst pole is erected.

Thursday 21st April: Fill large circuit breaker terminal block with bichemical insulator, Transpower Bromley Substation.

Above Steve is bracing to secure the large cast-iron circuit breakers in case of future earthquakes. These multi-tonne machines ripped their floor restraining bolts out during the magnitude 6.3 Christchurch earthquake.

One of the circuit breakers.

Analysis: Live line work

The possibility exists with overhead where the power cannot be de-energized. Line mechanics gain qualifications to work in these situations, two I know of are 'hot stick' and 'glove and barrier'. I have not yet witnessed 'hot stick', but I have seen 'glove and barrier' on two occasions, one at West Melton and one at Darfield. Both were 11kV and both were replacing poles with old style switching equipment with new style switching equipment.

Removal of existing pole:

'Glove and barrier' involves the use of high-voltage rated gloves, gauntlets on the line mechanics, and the use of large insulating sheets clipped to all live parts of the lines and pole. The live lines are disconnected from the pole and associated insulators whilst being held in place using a large fully-insulated extension arm attached to the HIAB crane on one vehicle. A cherry picker vehicle allows the line mechanics to work on the lines. A point of note is the last extension of the cherry picker truck before the bucket is fully insulated. All vehicles are bonded to earth and together as part of the process.

The existing pole to be replaced

The new pole (minus switchgear) to go in.

Insulators being attached

The last extension of the cherry picker

Cherry picker bucket ready with insulated pads and clips

Earthed vehicle

Full safety harness

The boys with HV glove and arm protectors

A 'link stick' and lugall winch hold the conductors aerially using strops to prevent any chance of the live conductors dropping and contacting the ground, causing short circuits and potential 'step voltage', which could kill people near the downed conductor.

The conductors held aloft temporarily by a fully insulated extension arm on the HIAB crane

The new pole being erected. The existing pole is held vertically by a crane and cut off at the base, then carefully lowered. The underground section is excavated and a new hole for the new pole is dug.

Installing the pole

Straightening the pole

Insulating covers being attached

Crimping conductors

Insulators removed

Switch operation demonstrated by me above..

The finished product. Note restraining wire in the ground, pole identifying number, and reflector for oncoming traffic.

This process was quite difficult to photograph, as the whole point of glove and barrier is to put a barrier up, which blocks electricity and photographers!

Pedagogy:

I should point out that different electrical companies use different 'glove and barrier', and 'hot stick' procedures, and Connetics' procedures may be different to other companies' ones. This I will be taking into account when teaching. However, these procedures all contain heavy safety elements and common sense, which simply saves lives.

Consultation with electricity supply companies may enable a 'live line teaching procedure' template to be designed that will satisfy the needs of all workers. It would be a 'best practice' procedure and would have to be accepted as a training tool to be used by CPIT to train lines companies' workers.

This process could also apply to cable jointing, as seen earlier in my blog. Cable jointing relies on a 'recipe' of instruction to complete different types of joints, and an error in sequence in completing a joint can be a $1500 mistake, which is why the ability to follow procedural instruction is crucial in the electricity supply industry, and demands significant teaching focus.

Anything can be achieved with excellent safe procedures, must see video see HERE.

My time in lines is over (temporarily), I'm off to the Substations Department until later in May, when I will go back to Lines to see helicopters running lines near Lake Coleridge.

My camera in action!

Week 11-Finishing the Bromley-Dallington build

2011-04-20T00:46:00.003+12:00

Poles in on the 66kV line from Bromley to Dallington, time to run the conductors (lines).

Work log:

Monday 11th April: Install conductors on Gayhurst Road.

Tuesday & Wednesday 12th & 13th April: Install conductors on McBratneys Road.

Thursday 14th April: Install conductors on Strathfield Road.

Friday 15th April: Install 2x poles and associated conductors for termination into Dallington Substation.

Analysis: Installing 66kV conductors on poles

Unprecedented in Christchurch, these lines are a 3-year 'stop gap' to keep electricity running in Eastern Christchurch. Easier to maintain and repair than underground 66kV cables, these are a sensible solution in the meantime until new underground cables can be run. Orion has produced a time line of work they want done on the Christchurch network HERE.

Now that the poles are in place, which are effectively the anchor points for conductors, the conductors can now be run. Preparation for this involves having drums of the conductor loaded onto big cable drum rollers on trailers.

Three cable drum rollers. These have a braking system on them. The concrete block is for restraining poles on the end of the run.

The conductor, referred to also as 'line' or 'cable'. Aluminium outer with steel wire core for hanging strength.

Cross section of the conductor. The aluminium outer cores can be seen and the inner smaller steel cores in the centre.

Labelling on the drum. The 6/4.72 HDAL refers to 6 cores of 4.72mm diameter high density aluminium. The +7/1.57 GSW refers to additional 7 cores of 1.57mm diameter general steel wire. 'Dog ACSR' refers to a name the manufacturer gives to the cable, i.e. Dog, Jaguar, Mink, Raven, etc. and ACSR is an acronym for 'aluminium conductor, steel reinforced'.

When running overhead conductors which are higher than other live conductors, care must be taken to avoid contact with those conductors. Insulators are attached to live conductors that the conductor being run may potentially come into contact with.

Attaching insulators to live conductors so contact cannot be made with the new conductor being run. Note the fibreglass ladder, not metal, so it itself is insulated.

More insulators attached

The insulators are designed to stay on once attached.

Once the insulator protection is in place, and rollers are installed in place on the poletop insulator arms, the conductors can then be run. Depending on the length of run, they can be pulled by hand. The trick is to thread them up and over all associated overhead services. High Voltage rated gloves are worn by all Line Mechanics in case the conductor does contact live conductors.

Conductors running through rollers for tightening

Pulling the conductor by hand whilst threading it.

On longer runs, the weight of the conductor needs to be pulled by something more substantial than by hand as it becomes too heavy.

Ensuring conductors don't contact other live conductors.

Conductors loosely in place

The conductors are then tightened loosely, and a temperature is taken at the height of the poletop insulators. This temperature is compared to a table and the correct tension 'droop' of the conductors is set. Temperature is taken to allow for expansion and contraction of the conductor. Once the correct tension is set using winches, the rollers in the poletop insulators are replaced with conductor clamps and 'line protectors' are installed.

Peter installing 'line protectors'. These are another layer of high tensile aluminium cores on the outside of the conductor cores. There's a knack to installing these!

'Line protectors'. These are for 'Dog' conductor.

Conductor clamp (undone)

Clamps tightened and finished pole. The 'line protectors' are clearly visible.

The 'ends' of each run are terminated using 'pistol grips'. These are specially shaped crimps that form conductor terminations at corners and junctions. The 'pistol grips' are tightened using hydraulic crimpers.

'Pistol grips'. These are also filled with paste to reduce aluminium oxidization, which is an insulator. Note the length increases once crimped, which is taken into account.

Crimping on the ground

Crimping in the air!

Task: Count the pistol grips!

I was also lucky enough to observe Independent Lines' Line Mechanics' solution to getting across the Avon River without contacting any of the sewer-ridden water. See below (note, this is not a 'standard procedure'!)...

The video below shows a tour of the circuit from Dallington to Bromley.

Next week: Final terminations and connection into the substation.

Pedagogical analysis: Electrical glossary/jargon

As with all trades, all electrical careers carry technical terminology. Some descriptions have multiple terms, for example, a conductor of electricity (I've used 'conductor' in this weeks' blog), can also be termed line(s), wire, cable, mains, straps, links, amongst many others. What is really interesting is the terminology changes for each different occupation. Clearly the occupation 'Line Mechanic' refers to conductors being 'lines', whereas Cable Jointers do use the term 'conductor'. House wiring electricians also use the term 'cable' and wire(s), but the New Zealand Electrical Wiring Regulations 1997 (2010 Revision) calls them all 'conductors', which is why I use that particular term.

Other terms are linked to the course theory. For example, what is voltage? A simple, accurate description of voltage is not really that easy. Analogies can help here; voltage can be described as electrical 'pressure'. If we consider the 'flow' of electricity, which is linked to electrical current, be compared to the flow of water, instead of valence electrons (the outer orbit electrons in an atom), which is what current actually is.

Voltage can be described as the pressure of the water in a pipe, current the speed of flow of that water, and insulation being the pipe outer, which is holding the pressure in. If the 'insulation' fails, the pipe will leak, however, electricity needs a conductor to 'leak' through. A spade or or digger bucket conducts electricity nicely, being made of metal, and can result in accidents if they contact a conductor. Unfortunately, even though humans conduct poorly, the can, however conduct well enough to be killed by electricity.

Electrical theory, being a subsidary of the physical sciences, uses a substantial amount of mathematics, so theory must encompass an understanding of mathematical terms, particularly SI units (The International System of Units (abbreviated SI from French: Système international d'unités) uses different terms for large and small numbers. For example; "'I travelled 120,000 meters to Tekapo", clearly kilometres is used to describe the distance more easily. 66kV=66,000 volts.

Trainees need to be encouraged to self-research terminology to understand it better. Electrical theory is difficult, and is widely regarded as one of the most, if not the most technical trade. There are literally thousands, if not millions of resources online, and other resources such as libraries should be encouraged. On-job instruction sometimes may not be good enough to satisfy a trainees' thirst for knowledge on a particular topic. The key is to reference the trainee to trusted sources.

For myself, as a tutor, familiarity with the multiple similar terms cable, conductor, wire, etc. is needed to explain theory to trainees/students. A 'pocketbook' should be encouraged, as most trainees and tradespeople carry one to take notes and appointments. Essentially trainees need to 'learn how to learn'. This I believe is not just part of becoming a tradesperson, it is part of growing up and becoming an adult.

Roger Sutton, CEO of Orion, who came down to see how the guys were going and to thank them for their awesome work. A true hero of Christchurch and more than happy to have a picture with some insane polytech guy!

Week 10 - Line Mechanic - The start of the Bromley-Dallington line build

2011-04-13T01:11:00.003+12:00

Well, a new week, a new trade!

Trucks 'locked and loaded'!

Work log:

Monday 4th April: Start installing 66kV poles on Strathfield Avenue.

Strathfield Avenue approximate pole locations

Pole vertical waiting for digger

Tuesday 5th April: Install poles down Gayhurst Road.

Gayhurst Road approximate pole locations

Tuesday Gayhurst Road in the rain

Wednesday, Thursday, Friday 6th-8th April: Install poles down McBratneys Road almost to the river.

The McBratneys Road approximate pole locations.

Lifting the pole

Reflection on first week in Lines:

On Monday, I went to the yard, where Phil (my primary contact at Connetics) introduced me to Peter (Head of Lines), who in turn introduced me to Carl (Leading Hand). Carl would be my supervisor also for at least the 66kV job we were to do (covered later in 'Analysis').

I had a fantastic time, getting the taste of a whole new ballgame in lines. Compared to jointing, where nearly everything is underground, this week involved digging three-and-a-half metre deep holes for treated Australian hardwood poles that are 15 and a half metres tall, protruding 12 metres above the ground. Insulators and crossarms were installed on the poles previous to erection, and poles were set according to a plan, some slightly angled on purpose.

Me holding the crossarm in place while 'somebody' gets the washers and bolts!

Difficulties included poor weather, traffic, hole dynamics, and the public. Once again, as with all Connetics work activity, safety is paramount, and all the Connetics workers I worked with showed a competence and confidence that put my mind at ease. As with the Cable Jointers, the Line Mechanics are extremely proud of their work, and set extremely high standards for themselves. I am going to refrain from commenting on the psyche of a Line Mechanic, I'll get to know them better first! Once again, I consider myself extremely lucky to be part of the Christchurch recovery and see history being made by these highly competent workers.

Analysis: Installing 66,000 volt poles in the ground

Installing such massive poles of wood in the ground in an urban area is no easy task. Navigating traffic, dealing with different soil types, poor weather conditions and avoiding other underground services are just some of the challenges facing Line Mechanics.

The reason that the 66kV overhead is being installed from Bromley Substation to Dallington Substation is to consolidate the damaged Christchurch power network due to the 22 February earthquake.

The 66kV overhead circuit plan

Four large 66kV underground cables were seriously damaged in Christchurch as well as the New Brighton Substation sinking, damaging the building and associated electrical equipment. The New Brighton Substation has been rapidly repaired already and had a 66kV overhead run to it, but it will be also relocated to Rawhiti Domain, where there is a lesser chance of further liquefaction. See HERE.

The first point if call for the Line Mechanic is to consult the 'plan'. A schematic diagram is available that shows the position the poles are to be inserted into the ground. This plan also shows other underground services, which gives the Line Mechanic an idea of where to dig.

The plan.

Network planners also visit the site previously and mark the ground in spraypaint where other services are and where the recommended position is for the pole to be placed.

Poles are then assembled, in our case, a nearby lot was converted to an 'assembly area' of sorts. Insulators, crossarms and rodent guards are attached to the suitable poles and the poles are subsequently transported to where they will be installed.

Assembling the crossarms

Rodent guard in place and attaching crossarm

Holes are initially dug very carefully, some by hand and some by very skilled digger drivers, depending on what the level of risk is of hitting an underground service. The Line Mechanics watch very carefully to see any sign an underground service (power cables, telecommunication cables, water mains, sewer mains and stormwater drains) has been exposed. Once the one-metre depth is hit, the chance of hitting a service reduces significantly, so the mechanical digger is then employed to dig to the 3.5 metre depth. The shape of the hole (in our particular case, as it changes) is a 'slot', the digger using a bucket about 500mm wide. The length of the slot varies depending on the amount of available room.

A 'pole hole', well, slot! Complete with water table water in the bottom.

Looking out for other services

Soil types can impede the correct depth being reached. Sandy and wet soil can 'cave-in' quickly, so the process is done reasonably rapidly, still whilst maintaining safety. An interesting occurrence for me was the range of different soil types that we struck while digging. We struck black coarse sand, jelly-like mud, yellowy beach-like sand and also clay.

Sandy soil..note how it's given way under the tarmac footpath.

'Jelly-like' mud.. might explain all the 'wobbling'...

To ensure rapid insertion, the pole is stood vertically next to the hole and held in place using the Line Mechanic truck's hydraulic crane and a heavy-duty chain. Once the 3.5 metre depth is reached, the pole is lifted and guided into the hole. This can be another challenge, as trees, overhead low-voltage and telecommunication cables must be avoided also. Skilled hydraulic crane drivers guide the poles in the ground.

Guiding the pole in

Once the pole is in place, the hole naturally starts to 'cave-in', but also the diggers replace some of the soil dug up, and also put gravel in too. Cement powder is added sparingly, to make the soil 'firm', but not so firm as the pole will be removed with difficulty. During refilling, the pole is monitored for vertical angle and that the insulators are aligned correctly. Poles that are set at purpose (less than vertical) angles are braced underground with short hardwood horizontal poles.

Carl measuring verticality using a 'plumb-bob'.

Looks all good to me..

Filling the hole

Awesome Pete getting a difficult pole lined up

Jono the Connetics CEO (right) on a site visit

Poles into the distance..

Finally, the soil is compacted, topsoil and grass seed is applied. Reflective markers are attached to the poles, and they are finished! Next; installing the cables (next week!)

My dream job!

Week 9 - Pump station, Timara 'loop joint', Fitzgerald Ave 66kV, base of Clifton hill.

2011-04-05T23:48:00.002+12:00

This is an account of my last week in Cable Jointing. Next week: Line Mechanic work!

Work log:

Monday 28th March: 11kV XLPE-XLPE-XLPE supply to pump station by estuary, joint from September quake torn apart by February quake.

'Torn apart' joint.

Tuesday 29th March: Corner Rothesay Road and Putake Drive, Timara Park. 11kV XLPE-XLPE and XLPE 'loop joint' (see analysis).

'Loop joint'.

Wednesday 30th March: Fitzgerald Avenue 66kV XLPE-XLPE joint of 3 x 50 Megawatt cables (see analysis).

The 3x 66kV XLPE joints done up.

Thursday 31st March: Fitzgerald Avenue 66kV again.

Friday 1st April: Clifton Hill by Shag Rock (now Shag Pile!) 11kV PILCA-XLPE-PILCA.

Under Clifton Hill.. 'run for the beach if the ground shakes'!!

'Shag Pile', the rock formerly known as Shag Rock!

Analysis:

Heatshrink vs cold shrink

After several 'discussions' with colleagues, I decided to really investigate this subject, with experts and my own research, as it appears to be controversial! I have found that those who actively use each type of shrink find it most useful to them, and think everyone else should be using the shrink they use!

So here it is; Andrew's unbiased observation of the Heatshrink vs. Coldshrink war!

Coldshrink pros:

Doesn't need heat or an open flame to shrink down, so can be used in hazardous situations.
Easy to use with regard to the shrinking process.

Coldshrink cons:

Can only be used on XLPE cable (unverified).
Has a 'shelf life' it must be used within.
Is weaker than heatshrink.
Using requires more accurate measurement than heatshrink.
Doesn't shrink down as much as heatshrink, so less room to use when installing before shrinking.
More expensive than heatshrink (but getting cheaper).
Impact protection not as good as heatshrink.

Heatshrink pros:

Copes better with bending stress and pressure.
Mechanically more robust.
Can be used with more cable types than coldshrink.
Is a time-proven technology.
Cheaper than coldshrink.
Flexibility in accuracy.

Heatshrink cons:

CANNOT be used in an explosive environment due to heat needed.

I can imagine some interesting comments following this wee analysis!

66,000 volt underground cable jointing

I had the rare privilege to observe the repair of one break in the 3x 66,000 volt XLPE 1600mm2 cables that run between Armagh Substation (an inside substation next to Orion head office) and Lancaster Substation. This repair demanded the skills of some of the best cable jointers in the country. The experts from Tyco (who sell the joint kits) were employed to do the jointing, as well as one of the best Connetics jointers.

Joining the cables is an exercise in precision engineering, with super-accurate measurements being required, and an especially high level of care and cleanliness. They generously allowed me to 'do up' some shearbolts on one termination, which resulted in a small amount of panic as I nearly damaged the XLPE insulation (but I didn't!)

Specialised and heavy-duty tools are used, along with the work being done inside a purpose-built marquee-type structure to keep external dust and weather out. A security guard is posted all night also.

I was told the cables were capable of transmitting 50 Megawatts (MW) of power each.

The worksite on Fitzgerald Ave

The faulty section of the cable has already been removed and the concrete it was encased in removed also. Extra lengths of 66kV cable are used to replace the faulty sections.

Ends cut off to the right length

Specialised tool for removing the semiconductor layer.

Sanding the rest of the semiconductor layer off. Finer and finer paper is used until the XLPE has a clean shiny finish.

Coarse sanding

The scale of a single 66kV cable

The concrete the original cable is encased in

Packaged up shearbolt

The same stripping tool is used to remove the XLPE insulation layer.

Measurements are made

Conductor is exposed

Shearbolts attached

Close up of shearbolts

Shearing bolts off

Shearbolts sheared off - terminals complete

Lighting in the night

Layers of insulation installed

Shrinking down the heatshrink

Shrink 'shrunk'!

3x completed joints

Heavy-duty cutter for big cables

Close up of a cross-section of the cable

The 'loop joint'

This joint is so called because it joins two underground cables that come from the same direction. It uses a special type of shearbolt as a consequence, and an underground encasing container, known ominously as a 'coffin'!

The loop joint seen here was installed at the corner of Rothesay Road and Putake Drive, in Timara Park, Burwood. It was done on two 11kV XLPE cables as part of Orions' network consolidation plan.

The terminal block

Blocks in place. Note the cables lying together.

The shearbolt. Multiple shear points are apparent. The uppermost one that has no thread engaged will shear.

Bolts in place

Shearing using the 'rattlegun'

Cables snugly trapped

A plug at the opposite end is attached using more shearbolts

Insulation is applied

Heatshrink shrunk on

3x completed joints

Attached snugly together

Earth cage installed

Laid in 'coffin'

Coffin lid attached

Jamie filling coffin with a bichemical resin

Still filling

Installing lids

The finished product; the 'coffin' gets extremely warm when the resin chemical is hardening

Finished

Finally, a couple of queries I need to address;

1) How will I introduce the specific use of these tools to my students?

Practical demonstration of the applications for the tools would be the most effective way to illustrate the use of the tools. The students will most likely have seen these tools in use already on the job, but the demonstration will involve safe and effective use of the tools also. I have videos of these tools in use that I can put on a moodle website also.

2) Attributes of cable jointers - how will I provide a sense of the camaderie of the cable joiners community of practice and sense of professional identity to my students?

In practical exercises, students could be set tasks in groups of two or four, depending on the task. This will instil an attitude of teamwork in the students, and also give them a sense of what the 'real world' will feel like.

'Team building' exercises that have nothing to do with jointing could be an idea, also, to give the students an idea of the flexibility required to perform a team task with a common goal where they are all on a 'level playing field' as far as skills and experience go.

This can be linked to Vygotsky's 'zone of proximal development' theory, where students belong to a community, or team, play their part in that team to obtain the meaning of the exercise, practice the exercise, and when completed successfully, gain a sense of identity that they belong in the team that completed the exercise undertaken. This will inspire confidence for the students when they attempt practical assessment.

Also the interaction amongst the team (particularly when problem solving) links up with George Siemens' Connectivism theory, where students will interact to obtain viable solutions for a common problem, and accept or reject ideas from peers in the team to make decisions on the task at hand.

And lastly, once on-job, the students will be moulded into the team environment by the team. If the individual does not become part of the team, both themselves and the team will be affected and performance will reduce until something 'gives'. The advantage in this situation is the student (trainee) demographic shows them to be younger and more flexible. Good leadership by experienced team members is particularly helpful during the trainees' learning stage.

And that's it! Next week: Line Mechanic!

Week 8 - Cable Jointing - North Parade lateral spread, QE2 Drive consolidation, Philpotts Rd consolidation, Pages Rd.

2011-03-30T00:46:00.002+13:00

Work log:

Monday 21st March: Worked at North Parade, Shirley to repair a low voltage XLPE attached to a bridge for a private right-of-way that had been severely bent (but still operating ok, amazingly!) by the riverbanks 'slumping' in the earthquake 22nd Feburary.

Slumping bending the low voltage XLPE

Steve showing off the bent section

Tuesday 22nd: QEII Drive near Marshlands Rd roundabout, XLPE-XLPE 11kV joint, network consolidation.

Wednesday 23rd: Philpotts Rd near QEII Drive, XLPE 11kV termination into kiosk for network consolidation.

Tightening 11kV terminations in kiosk

Thursday 24th: Philpotts Rd again, more kiosk terminations and XLPE-PILCA joint.

Finished kiosk terminations

Friday 25th: Pages Road near bridge, PILCA-XLPE-PILCA faulty 11kV cable replacement.

These rings are the modern alternative to lead wiping.

Liquefaction causes the building to sink, pulling overhead connections off.

Riverbank 'slumping', causing the buildings to come away from the car park.

Analysis: Cable jointers' specific tools

As with all trades, cable jointing carries with it specific tools for specific purposes. For Connetics jointers, there are tools suited to PILCA (paper insulated lead covered armoured) cables as well as modern XLPE plastic insulated cables. One advantage of having jointers from all over the country here is that we can see what tools are being used elsewhere in similar situations. For example, Northpower use heavy-duty remote controlled hydraulic cutters, which cut, obviously, but also replace spiking guns.

Connetics has observed these other tools and purchased new ones to allow more efficient operation for the jointers, such as reciprocating saws.

The cable jointers' tool box is interesting, particularly from an industrial electricians' point of view.. lots of knives, cutters and crimpers are apparent. A selection of tools are shown below.

Jeff's toolbox - All in immaculate condition. He sets a great example.

Nice new reciprocating saw. Used to cut cables and has replaced the good old hacksaw. The hacksaw is still used for cutting steel armour on PILCA cables.

Discussed earlier, the precision stripping tools for XLPE and the semiconductor layer. They're inside a wooden stool used to prop cables up above the mud in the bottom of the hole. Water seriously compromises the integrity of joints.

The 'rattler', or more formally, the impact driver is used only for shear bolts.

Car jack stands for holding the cable off the ground also.

Hook knife

Core cutter

Stripping knife - No two are the same and the jointers' all have their own favourite ones!

Outer insulation double purpose knife

Insulation stripping knife

New technology.. kevlar string used to cut plastic insulation without 'nicking' internal neutral screen conductors

Squarehead pliers designated by Tyco to be used to remove semiconductor layer.

Large crimper

Battery hydraulic crimper

As with all trades, maintenance of tools is paramount. Knives must be kept sharp, tools must perform correctly and be clean. Dirt or poor cuts on cables reduces the effectiveness of joints and lifetime, particularly on higher voltage cables.

Analysis: What makes a good cable jointer?

As an 'outsider', it has been interesting to see the psyche of the cable jointer and what 'makes them tick'. Particularly more so with the visiting jointers from other parts of the country. It's almost humourous how easily all these guys 'click'. Even the Christchurch jointers are noticing this! They refer to themselves as a 'breed', which is correct! Whare, a very professional and experienced jointer from Northland, expressed to me that he was really happy to see the young guys were the same as he and his colleagues once were also. The jointers who are all here have picked up a catchphrase coined by Steve Bright; "That's how WE roll"!

As an aside, I had the great privilege to be invited to a BBQ at Blue Skies in Kaiapoi organised by the Northpower and Vector jointers, and had a fantastic time!

"That's how WE roll!"

The first attribute every cable jointer will tell you is the most important is that they MUST be a team player. Trust and reliability are important to all jointers, and if those attributes are not apparent, then the team will not perform efficiently or optimally. All crews work in twos, and are almost psychic in their teamwork.

The next attributes would be pride in your work and good workmanship. A joint must be done 'right first time', particularly when working under pressure where things can be forgotten. Joint kits are not cheap and if one step is missed, the entire day or job can be wasted. I like to refer to joints as 'mechanical works of art'. I personally have done thousands of electrical terminations, and understand the quality of a good termination can be life-saving. In the cable jointers' world, lives and economies depend on the quality of the joints.

Lastly, flexibility. There are numerous challenges that cable jointers need to face, from weather to earthquakes (!), to rubberneckers, bugs, rapidly rising water tables, road access, and numerous other issues. Jointers need to be able to 'think on their feet' and find solutions, quickly.

Teaching ideas: Practical demonstration/ formative and summative assessment

There's no way I will become a Master jointer in 2 months, so CPIT will be organising jointers to come in and demonstrate jointing to students. I have identified several individuals we could approach as good educators, and assessors also. With kits being so expensive, multiple summative resits are not going to be an option. On-job summative assessment will have to be used, and possibly video evidence submitted from some students. I will video these demonstrations and use them in moodle for future students to watch and learn from. I'll be asking nicely for a decent digital video camera when I get back..! Flexibility in tutoring, as on the job is going to have to be a quality I as a tutor will need.

And that's it! Week 8 over.. Next week will be my last week in jointing, and hopefully I'll see some 66kV repair on Fitzgerald Ave.

Weeks 4-7: The February 22nd 2011 M6.3 earthquake and the start of the repair of the Christchurch distribution network.

2011-03-22T22:26:00.003+13:00

This post covers the week of the Christchurch Magnitude 6.3 earthquake and following to Friday the 18th March, the Memorial day.

Work log:

Monday 21st: Worked with Reece at Nunweek park hockey park terminating 11kV XLPE into a kiosk.

Tuesday 22nd: Attempted to finish the kiosk with Reece. Job abandoned for technical reasons. Mag 6.3 Quake hit at 12:51pm.

Wednesday 23rd February - Monday 7th March - No work - Quake recovery.

Monday 7th: Averill St 11kV quake damaged PILCA-XLPE -PILCA repair with Steve.

The post-22 Feb quake 'job desk' at Connetics

Connetics and associated supply industry workers at a promotional BBQ breakfast

My first quake casualty-11kV previously joined cable in sewer-filled hole.. nice.

Faulty quake-bent 11kV PILCA cable, River Road.

Steve jointing 11kV Averill St with the hard case boys from Transfield, T and Peachy.

Tuesday 8th: Palmers Road 11kV severe quake damaged PILCA-XLPE-PILCA-XLPE-PILCA with Steve

The cable testing trailer display.. gives estimates in meters how far along the cable is faulting. Flash piece of machinery.

Steve the test tech placing clamps on the cable under test

Quake-kinked PILCA 11kV cable

My XLPE 'half a joint' with Steve!

Wednesday 9th: Palmers Road same as previous day

The locals are fed up.

3x quake-kinked 11kV cables. The final solution was to abandon multiple joins and run a new cable.

Thursday 10th: Gayhurst Road 11kV PILCA-XLPE-PILCA with Steve

Friday 11th: Bridge Street and Estuary Road 2x joins 11kV PILCA-XLPE-PILCA with Steve

Bridge St 11kV from Bromley Substation. Note riverbank 'slumping' above Steve (which caused the fault), who is using his nice new sabresaw to cut..!

The New Brighton Substation 33kV transformers and control building that sank 2m due to liquefaction.

The Pleasant Point yacht club slumping damage

The Bridge St bridge slumping damage. We received a visit from structural engineers.

Monday 14th: Inverness St 400V Neutral screen T repairs with Steve and Robbie

Tuesday 15th: Landsdowne Terrace 400V boundary box and neutral screen repairs with Steve and Robbie and the 'Northland boys'.

Boundary box safety tagged by the 'test room' team.

The damage to the road, which caused the damage to the cables. We measured the fissure depth at 2.4 metres.

Wednesday 16th: Santa Rosa Avenue, Mt Pleasant 400V quake damaged Tees.

The boys in the Tee hole while demolition men remove the adjacent house's chimney.

Tee under preparation

Finished Tee with 'quake strain loop'.

A typical example of a Mt. Pleasant house. They got a hiding.

Marine Parade red-stickered house. Sickening.

Thursdsay 17th: Cnr Pages Rd and Anzac Dr 11kV PILCA-XLPE-PILCA quake fault repair

The quake-damaged PILCA (Note steel and lead armoured) cable. The trunking in the broken concrete behind houses the faulty 66kV cable that was replaced by an overhead line is super-record time.

Robbie with the finished product.

Friday 18th: Quake memorial day.

Personal statement

Firstly, I'd like to express my absolute sorrow for all of the victims of the Christchurch aftershock earthquake that struck at 12:51pm on 22nd February 2011. I refer to the victims as 'the unlucky ones', the reason being I believe it was pure luck that determined who died or who survived the earthquake. My wife Emma and I were just leaving a car park on Bedford row just around the corner from the CTV building when the quake struck. I believe I now truly know the meaning of terrifying. We were extremely lucky that we were in the shadow of the newly constructed IRD building, which had been built extremely sturdily and protected us.

The sights we witnessed on our flight out of the city centre will live with me forever. Our house received further foundation damage. Luckily the structure seems intact. In the two weeks following the quake we had no power for a week, and no water or sewer for 3 days. We did volunteering work in the community to help people out (as you do). I was extremely humbled by how New Zealand and the World came to our rescue, and how the community rallied to help each other, even in our wee street.

I was going to do an analysis of heatshrink vs. cold shrink, among other individual items these weeks, but instead I would like to pay tribute to the heroes I am having the extreme privilege of working with.

Starting at the top, the management and administration staff of Connetics have shown fantastic resilience, and superb organisational ability to coordinate the reconnection of power in our broken city so rapidly. Employees and visiting employees from Vector, Transfield, and several other power supply companies have been given motivational talks, BBQ breakfasts, psychology talks, and even stand-up comedy! These examples of exceptional leadership, combined with site visits of the repairs being done, have led me to make the comments I have. I have been watching in awe of the performance.

The 'coalface' workers simply keep going. Quality and unwavering performance in the face of the biggest natural disaster to strike this country has been the hallmark of these workers. Yes, they are paid to do the job, but many carried on working with broken homes that had no water, power or sewer.

All of this is combined with nightly 'wake-up call' aftershocks, which get the adrenalin going and makes getting back to sleep difficult, radical future earthquake predictions from inconsiderate attention-seekers, scumbag looters, and the ever-present threat of the Alpine fault or more unknown quake sources make for difficult living, let alone working.

I salute all power workers, all Governmental workers, USAR legends, Police (Kiwi and Aussie), core infrastructure workers, health workers, engineers, student army members, Red Cross, everybody who cared and donated, and finally, the awesome Christchurch people.

Rise up, Christchurch.

Week 3 - Cable Jointing - Halswell Junction Road, Tradefit, Timaru 33kV

2011-03-15T10:16:00.003+13:00

Far out time's going fast on this ASL (academic study leave)! Week 3 over!

This week's log:

Monday: Halswell Junction Road with Jamie. 11kV XLPE-HDPE (high density polyethylene), spiked.

Good 'spike'.. right through!

Tuesday: Orion EAC (entry approval certificate) course in the morning at CPIT Tradefit, afternoon Ensors Road with CJ and Nick to break into a 11kV PILCA with two XLPE for a kiosk.

Steve shows CPIT students the inside of a kiosk

Wednesday: Timaru with John, Terry, and Mark to do 33kV 1200mm2 3x single core XLPE.

Ends prepared for joining

Thursday: CPIT tradefit sub terminations with Steve.

Friday: Halswell Junction Road 11kV XLPE-PILCA with Steve

Analysis:

33,000 volt joining in Timaru

On Wednesday I travelled to Timaru to see John, Terry and Mark joining 33kV cables for Alpine Energy. Cables come in drums of (?) length, and need to be joined the length of the full (?) run to a new substation.

The joining is done deep underground, under all other services. Connetics use a open-bottomed container as weatherproofing and for protection of the jointers.

The 'joining container'

The cables are 3x single 1200mm2 aluminium with neutral screen XLPE and MDPE (medium density polyethylene). Alpine's specification was to use crimp joiners rather than the newer 'shear bolt' joiners.

Cable description on side

1200mm2 aluminium 33kV cable

Both ends of the 33kV cable are stripped and prepared with the minimum wastage possible. They are measured and aligned for joining.

Stripped and ready for joining

The joint is performed using a large hydraulic crimper, which is a very flash and expensive piece of equipment! The cable is stripped back to measurements specified by the joint manufacturer, with the usual extra care for the semiconductor layer. Correct measurements are crucial to this operation, with no room for error (no pressure!).

Crimping done

John would like to lay claim to his 'John's jack system', which ensures the crimper is always at the correct height using a heavy duty hydraulic vehicle jack! Brilliance!

John's jack!

John in action

Seeing John and Terry (the joiner guru!) in action was great!

I travelled back, pausing at Highfield Road to stand on the Greendale fault, the cause of out M7.1 quake and $5,000,000,000 of damage in Canterbury. Kinda odd that Highfield Road is next to fields that have been pushed up... High.. sad I know...!

On Highfield Road, the Greendale fault line

Postscript.. NOTE: This is still before 22nd February. Post-quake coming soon.

Hazards

The following hazards are associated with cable jointing:

Electricity (obviously!) in kiosks and nearby cables

Open flame/heat when heating cables for stripping and when heating heat shrink

External noise and the driver for shearbolts

Tools/sharp ones in particular for stripping

Other contractors/public (including 'rubberneckers', which there are a surprising amount of!)

Vehicles/heavy and diggers etc.

Weather wind/sun/rain

Dust, when windy

Fumes from heating pitch in PILCA cables

Oils on PILCA cables

Sharp edges

Holes/cave ins

Kiosk and sub doors

Dehydration

Lead poisoning

Slips

Teaching methods for hazards:

Brainstorming - drawing on previous knowledge of students

Practical (individuals or teams depending on formative or summative assessment)

Scenario work - field trip or photos/video (moodle?)

The semiconductor layer

The semiconductor layer is a thin layer in HV cables that usually surrounds the immediate first conductor insulation layer (usually XLPE). The function of the semiconductor layer is to 'spread the charge' if the XLPE layer fails insulation-wise. Special tools are used to strip the semiconductor layer carefully and NOT damage the XLPE layer. This layer is a modern measure used on HV cables. A special 'strip tool' is used to strip the semiconductor layer nicely without damaging the XLPE layer.

Me using semiconductor layer stripper

Me stripping off semiconductor layer

Another enjoyable week!

Link to HV cable document (good)

Next time: The 'block' starting 21st February to 17th March. Apologies due to delay caused by the February 22nd Magnitude 6.3 Christchurch earthquake which devastated Christchurch and killed hundreds. RIP the 'unlucky ones'.

Week 2 - Cable Jointing - Tradefit, Halswell Junction Road - Lead wiping

2011-02-15T20:24:00.004+13:00

Well, I'm getting the hang of this! Apologies for lateness; busy weekend!

Me working!

This week I've decided I'm going to be more brief about what I'm doing and focusing on certain areas that I feel I will need to teach. I will give a brief description of what I've done for the week, but the focus will now go onto producing course material. The photos on here are not even a tenth of the pics I have taken, so i'm building up the resources!

Week breakdown:

Monday:
CPIT Tradefit site sub, 11kV and 400V XLPE joints into the back of circuit breakers with Steve. Also Inspection of terminations in boundary boxes on Russley Road.

CPIT Tradefit site

New type boundary box

New type boundary box with cover off

Tuesday:
Remove parts from old breakers at Connetics and install in two breakers at CPIT Tradefit site sub with Steve.

Wednesday:
Halswell Junction Road (where new motorway will attach), 11kV XLPE-PILCA including 'spiking', phase testing with Steve.

Halswell Junction Road - underground and overhead

Thursday:
Halswell Junction Road 11kV XLPE-PILCA joint with Steve.

Friday:
Operational requirement work at Connetics site preparing for Orion EAC course Monday.

The first skill I wanted to cover in detail is lead wiping. This is soldering on a large scale to maintain older cable waterproof and earthing integrity when joining with another cable using the Tyco kits. This skill is rare and Orion in their foresight have elected to keep using it even though other methods are available.

The lead wiping is to construct a blob of solder connecting the steel armour of the outside layer of the cable onto the stripped internal lead armoured layer. This also stops the pitch (tar) under the steel layer seeping into the joint.

I decided to video this being done (I've taken a lot of photos of it being done already) and this will be another way of keeping the skill alive. The video will be integrated into a 'moodle' website that I will be developing to consolidate the teaching with.

Video (apologies for right-hand decorative bar, still getting used to Windows Movie Maker on Windows 7):

The next item I wanted to cover in detail was the 'spiking' of cables. This is the 'last line of defence' for cables to ensure they will be isolated (disconnected from the supply voltage) before being cut into. All possible testing is done beforehand, but to be fully sure, a metal spike is driven into the cable using a blank cartridge (44.40 calibre) tool. If the cable is still live (very rare!) then the spike will cause protection (fuses or circuit breakers) upstream to open, and ensure the cable is safe to work on. The cartridge is operated using a long cord so distance can be maintained for safety (paramount!).

The cartridge

The 'spike'

Hole in cable left by the 'spike'

And another.. Shear bolts.
Shear bolts are used in the final connectors to create the actual cable termination(s). The beauty of shear bolts is that they are designed to shear off at a certain torque, that being the best possible torque to make the connection safe and conductive. A similar system was used on aircraft carrier catapults historically, to hold the plane back until the steam pressure that drove the catapult reached a high enough level to launch the aircraft.
The bolts also eliminate the effect of aluminium oxide, which is an insulator and forms on aluminium surfaces within minutes of exposure to air by 'grinding' the oxide off the surface of the conductor. The inside of the bolts contain a white conductive paste to further assist conduction.

Here are two videos of shear bolts in operation. The first using a battery driver to shear, and the second (due to a flat battery!) using a socket driver.

To teach these skills, practical demonstration is a must. Tradespeople being predominantly visual/kinaesthetic learners, then teaching focusing on these learning styles is paramount. Vygotsky's 'cognitive apprenticeship' theory is fully applicable here and is commonly used in the trade (as with most trades) with the 'master and apprentice' formula being well used at Connetics. Due to the high cost of jointing kits, and the 'take your time so you do it right' attitude, practical summative assessment should be restricted to one attempt only (if possible). On job assessment could be used as the resit? Certainly this is something I need to think about.

Tip this week: Using kevlar string to cut through the outer layers of insulation to the neutral screen enables you to not damage the neutral (earth) conductors (Steve).

Looking forward to next week: 33kV jointing in Timaru!