Tasmanian Times

The individual has always had to struggle to keep from being overwhelmed by the tribe. If you try it, you will be lonely often, and sometimes frightened. No price is too high for the privilege of owning yourself. ~ Friedrich Nietzsche

The individual has always had to struggle to keep from being overwhelmed by the tribe. If you try it, you will be lonely often, and sometimes frightened. No price is too high for the privilege of owning yourself. ~ Friedrich Nietzsche

Economy

What is your view on what caused the Basslink failure?

*Pic: Pete Godfrey sent in this diagram, Comment 16. Pete says: “#4 kelvin, I have never seen an armoured cable that did not have a layer of insulation under and over the armouring. Especially one designed to be underwater. The picture I have of the Basslink cable that I hope Linz can attach to the article shows that it has the cable, then insulation, then a lead sheathing, then insulation, then armour, more poly sheathing, then string. I cannot see how the oil from the paper insulation can possibly ooze out unless the lead sheath was damaged also. It would also mean that the poly sheathing over the lead sheathing was damaged too. Meaning the cable was punctured.”

image
*Pics: The damage … and the culprit? Geelong Star, before its renaming. And below, Basslink cable damage: the gouge. What caused it … ?

image

Basslink from a technical perspective

This is the fourth article* on what started out as a single article trying to focus on the “paucity” of technical knowledge on the Basslink Saga. My aim was to indicate (with a degree of plausibility) what caused Basslink to fail …

… Something, I believe, that the public would very much like to know.

The original scenario has been improved courtesy of many good comments coming from readers … either adding or reinforcing some strategic points.

However, there are two important points mentioned in my first article ( HERE: Likely cause of Basslink failure is the Geelong Star ): One alluded to and the Second materially corrected by one commentator.

These have now become of paramount importance; these two points have a relationship with each other.

Firstly, perhaps Basslink may contain an intrinsic protection feature against internal faults? Cables, by their nature, rely on materials technology for their safe function. Many hidden and clever safety features are incorporated in these materials that a casual examination would not reveal.

The big enemy of submerged cables in the event of damage is from water ingress. The amour provided to a cable can only protect against a known level of potential external threat. It is, however, possible to design a cable which will not rupture the integrity of the protective alloy sheath from an internal failure – so preventing water ingress and the need for extensive cable replacement.

Unlike the external threat, the amount of energy expended on an internal failure can be controlled by the protection system. That amount of energy can be allowed for in the design of the cable’s mechanical construction and the ability of materials to withstand violent heat, pressure and sheath expansion for the very short time before the protection equipment operates.

Therefore, for spot internal insulation failure the cable could have inbuilt protection. However, the cable manufacturer would be needed to verify if this type of protection has been incorporated into the Basslink cable design.

Secondly, in the first article ( HERE: Likely cause of Basslink failure is the Geelong Star ) it was noted that the cable seemed to have been hit by a suitably-shaped moving object cutting obliquely a single element of the outer binding. This left its inner strands separated and protected from any hot gases by the striking object.

At this time I had wrongly stated the strands were metal. One of the commentators corrected me and it does appear that the strands are polypropylene. Polypropylene melts and fuses easily.

If an internal insulation short was the problem, then assuming the cable sheath did burst hot gases would have escaped between the gaps of the individual main armour cables. These hot gases would have melted the polypropylene rather than the neatly cut strands as shown in the insert.

To me the swelling on the cable, which is caused by electrostatic forces around the point where the short is established, does not appear to be anywhere sufficient to rupture the sheath. Indicating that the protection system functioned as designed.

During the period these articles have run there has been a considerable release of information on the Insurance, Basslink corporate, Hydro, and State Government fronts.

Insurance seems to have accepted a force majeure claim from Basslink. This does not indicate if the cable was subject to external force or had an internal failure. Force majeure in English law has a degree of foreseeablility added against the original French version. Which means that the circumstances are mostly likely the criteria; not the type of actual type of failure.

The State Government seems biased toward internal failure. Perhaps this stance is related to regulations for fishing vessels. These laws as far as currently determined, seem to indemnify fishing vessels striking the Basslink from any liability or wrongdoing.

Hydro does not accept force majeure and by default it would seem to believe that the cable was damaged by a foreseeable event that possibly could have been prevented.

No doubt all three entities have their own interests at heart for their positions.

This exercise over the last weeks has only been to to find what did cause Basslink to fail …

… Therefore what is your view … external trauma or internal failure by causes unable to be determined?

*Bio of Kelvin Jones: Technically trained and qualified in the UK by a major electrical engineering manufacturing company in Power Engineering and industrial electronics, moving in to defence systems, commissioning RADAR and development of underwater weapons. TV transmission, field work and commissioning industrial electronics and HVAC carrier protection. Research in cellular and fibre optics communications. Field work on scientific, bio, and medical instrumentation with extensive experience on Medical Imaging particularly CT scanners and Nuclear imaging. Mature age university studies in computer science and Technology with emphasis on the viability of renewable energy technology on legacy power grids. Green by practical evolution.

SUNDAY, November 6 …

All about Submarine Power Cables, HERE

*THE THREE earlier articles on Tasmanian Times …

Basslink: The very secretive State Government …

Is a door flying open on Geelong Star … ?

Likely cause of Basslink failure is the Geelong Star

Mercury: Hydro’s year of living dangerously

• John Hawkins in Comments: Steve Davy has recycled the Hydro press release in his Mercury article referenced above. We are very badly served by the Examiner and the Mercury who employ nobody who will conduct investigative journalism. Well done Kelvin and TT … for pursuing this the most important Tasmanian story. This complex matter will end up in the courts as one of the parties involved is not bound by the Silence of the Lambs in Tasmania. Basslink will sue over nonpayment and the can of Hydro worms will be sprung wide open. Those who rule the roost in Singapore do not buy silence.

• Pete Godfrey in Comments: #4 kelvin, I have never seen an armoured cable that did not have a layer of insulation under and over the armouring. Especially one designed to be underwater. The picture I have of the Basslink cable that I hope Linz can attach to the article shows that it has the cable, then insulation, then a lead sheathing, then insulation, then armour, more poly sheathing, then string. I cannot see how the oil from the paper insulation can possibly ooze out unless the lead sheath was damaged also. It would also mean that the poly sheathing over the lead sheathing was damaged too. Meaning the cable was punctured.

37 Comments

37 Comments

  1. Pete Godfrey

    October 28, 2016 at 9:21 am

    Kelvin, the diagram i have of the cable makeup does not show any poly covering of the armouring.
    Usually there is a poly coating over the armouring, I would suggest that in an undersea cable the armour would definitely be protected from the salt water.
    The photo in your article of the damage appears to show rust or some other material oozing from the cable.
    It seems from that, that the poly coating is damaged and the steel wire armour is rusting.
    We need more information.
    The fact that Hydro do not accept that it is a force majeure seems to point to external forces, and also to them doing a bit of backside covering.
    I guess that they want as much compensation as possible to cover for the fact that they foolishly ran the dams so low.

  2. Chris

    October 28, 2016 at 12:42 pm

    When the cable goes bottom up, we should buy it and p..s the “owners off, and add to Hydro’s debt no doubt .
    A second cable would of course put up the rental to $200 million per year and let us import power till the cows come home and the dams run dry.
    Why were the transponders turned off on the Geelong Star, Shirley there is a trace upon shipping movements and if there aint who let them off?
    Anxiously awaiting my next power bill and its breakdown into its component parts:-
    1. Actual power consumed.
    2. Fixed rising costs.
    3.Solar credits giving the HEC a free ride courtesy of our corrupt Government.
    4. Amounts transferred to the Sustainable Lying Timber industry courtesy of the Abetz demoted Minister.
    5.Amounts transferred and required to prevent the HEC trading while insolvent
    6. Lovely Groomed words to ally my suspicions of mates rates in this Lieberal mob.

  3. TGC

    October 28, 2016 at 1:45 pm

    “…our corrupt Government.” #2 has the proof?
    or just doing hysterics?

  4. Kelvin Jones

    October 28, 2016 at 3:59 pm

    Pete… The original drawing of the cable I used was not clear. Second opinion seems to be correct, and when I look more carefully I found a note indicating it had a polyethylene roving.

    One could expect some rust from a flash scorched armour after several weeks.I would guess the armour is protected from rust by electrolysis technology. When flash burnt this protection is lost.

    This a very cleverly designed cable with first class quality control.

    The Ouse is the fluid they embalm the paper layers with. Apart from the insulation properties it also helps to prevent water ingress in event of rupture. It is this feature of this class of cable that was a primary consideration in its selection.

    This also brings another point…. As Hydro keep pointing out why was 65km of cable left on the sea bed. Hydro want it lifted for test.

    As mentioned in the articles cable failures are common in the Northern hemisphere. No doubt legal claims are just as numerous. May be the act of Basslink to leave what may be perfectly good cable on the sea bed is a well practiced legal strategy for claiming insurance?

    When you get to legalities it is another ball game which is enacted around the physical problem.

  5. John Hawkins

    October 28, 2016 at 8:00 pm

    Steve Davy has recycled the Hydro press release in his Mercury article referenced above.

    We are very badly served by the Examiner and the Mercury who employ nobody who will conduct investigative journalism.

    Well done Kelvin and TT for pursuing this the most important Tasmanian story.

    This complex matter will end up in the courts as one of the parties involved is not bound by the Silence of Lambs in Tasmania.

    Basslink will sue over nonpayment and the can of Hydro worms will be sprung wide open.

    Those who rule the roost in Singapore do not buy silence.

  6. Frank again

    October 28, 2016 at 9:04 pm

    Now, whilst we at it: “Here is something Rene’ and Erich may like to find useful to practice their German language skills:

    Diesel-Kaffee: Energiewende in Australien
    Leben mit der Energiewende

    “Energiewende in Tasmanien!?

    https://www.youtube.com/watch?v=eePXTKRZDNY

    Auf der kleinen Insel südlich von Australien sollte es eigentlich regenerative Energien geben, doch statt dessen werden Dieselgeneratoren betrieben.”
    Auskopplung Leben mit der Energiewende TV –
    244. Sendung

    “Eigentlich ist Tasmanien zu 100% regenerativ versorgt. Eigentlich! Aber der Ökostrom wird ins Mainland abtransportiert, weil sich Ökostrom teurer verkaufen lässt. Zurück kommt dreckiger Braunkohlenstrom. Doch dann gab es eine Bruch im Erdkabel und die Stromversorgung brach zusammen. Denn in Tasmanien gab es zur gleichen Zeit eine Dürreperiode. Der Wasserstand in den Staubecken war zu niedrig und so hatte Tasmanien weder Öko- noch Braunkohlenstrom.”

  7. john hayward

    October 28, 2016 at 10:19 pm

    #4, Kelvin. The “legalities” is a ball game that isn’t seriously played down here, which greatly emboldens those playing under the Tas Govt flag.

    John Hayward

  8. Second Opinion

    October 29, 2016 at 10:09 am

    I have found the local blogger who has posted good images of the Basslink cable. He might even live near you. Just look around for the various antenna arrays adorning a house.

    (link removed)

  9. Second Opinion

    October 29, 2016 at 1:15 pm

  10. T. Thekathyil

    October 29, 2016 at 1:38 pm

    #3 ‘“…our corrupt Government.” #2 has the proof?’

    Possibly not but I have.
    http://tinyurl.com/j3t5vco

    Unredacted version should be available from your local member.

  11. Jon Sumby

    October 29, 2016 at 3:37 pm

    The link in comment 8 should be removed by the editor I suggest. My security program gave me this warning:

    The certificate that the server presented has been revoked by its issuer. This means that the security credentials presented absolutely should not be trusted. You may be communicating with an attacker.

  12. Simon Warriner

    October 29, 2016 at 11:08 pm

    re 11, I got to the letter in question straight up, no silly messages.

    Sorry. wrong link, you are correct.

  13. Second Opinion

    October 29, 2016 at 11:09 pm

    Nothing so sinister Jon,
    For some reason, if I attempt to copy and paste when using an IPad, nothing happens if I try to paste into an empty page, as in this case. I will stab at the keypad just to fulfil that need, and in this case, forgot to remove it before posting.
    I did not notice the Chttp until it was put up on the page,
    hence the repost.
    Settle down now Jon.

  14. John Hawkins

    October 29, 2016 at 11:39 pm

    #9

    It is interesting that Second Opinion is trying to destroy this blog.

    Does the Editor know his identity?

    Why would he wish to do this?

  15. Jon Sumby

    October 30, 2016 at 12:27 am

    The link in comment 9 should be removed by the editor I suggest. My security program gave me this warning:

    The certificate that the server presented has been revoked by its issuer. This means that the security credentials presented absolutely should not be trusted. You may be communicating with an attacker.

  16. Pete Godfrey

    October 30, 2016 at 12:29 am

    #4 kelvin, I have never seen an aromoured cable that did not have a layer of insulation under and over the armouring. Especially one designed to be underwater.
    The picture I have of the basslink cable that I hope Linz can attach to the article shows that it has the cable, then insulation, then a lead sheathing, then insulation then armour more poly sheathing then string.
    I cannot see how the oil from the paper insulation can possibly ooze out unless the lead sheath was damaged also. It would also mean that the poly sheathing over the lead sheathing was damaged too.
    Meaning the cable was punctured.

  17. Second Opinion

    October 30, 2016 at 10:31 am

    I notice Jon Sumby’s comments are being made before I see my comment posted on the page, which in this case; #9, was some hours!*

    I do see in the literature that the insulating paper, wound and then impregated, is semi-conductive. Thoughts?
    I will not link to it .

    Ahh I do hear the baying of hounds. Must be the two Johns I fear most. Into the tanglewoods trusty steed.

    *Ed: That’s because the one-man band can’t keep up…

  18. Kelvin Jones

    October 30, 2016 at 11:25 am

    #17… Second Opinion… Quick thought if the insulation is semiconductor. It may be being used for protection sensing. Possibly temperature?

  19. Chris Harries

    October 30, 2016 at 12:11 pm

    Whenever there is an aura of government secrecy – such as neither confirm nor deny – the best thing to do is to assert what’s likely and make that a ‘fact’ in the public eye.

    This throws the ball in the government’s court to make a choice: either demolish that perception with a credible alternative or to live with what the public believes to be so.

  20. Kelvin Jones

    October 30, 2016 at 12:24 pm

    It could also be that medium used to impregnate the cable has a stress equalising effect. I would love to have a lecture on this system from the manufacturer.

    When this is all over may be the manufacturer will oblige and I will find out how accurate this investigation is.

    Thanks for the pics, particularly the samples in staged cut back.

    The more I see the more I think there is protection from rupture from an internal flash over.

  21. Second Opinion

    October 30, 2016 at 5:40 pm

    My own thoughts on using a semi-conducting mass insulation would go to draining of the charge established during each phase of operation. Much like a high value resister is used to discharge electros. Apart from that, it would level out any standing waves that traverse it’s length.
    The immersion liquid would be just sufficient to elinimate air pockets.The cable has a lead sheath immediately outside the insulation layer, and it seems to be a molten bath, so no excessive liquid is good. I’m travelling so can’t respond too readily.
    There was a problem with the link, which has been rectified.
    Promise!
    The Pirelli cable as shown in the link, may not be the final design. It looks like a pre-production sample.
    Much of the JAP hearings went to examining the earth-return “feature”. After an earth-return was rejected there might have been changes.

  22. Second Opinion

    October 31, 2016 at 12:07 pm

    This document from Prysmian Cables, looks like a PowerPoint presentation, and mentions Basslink on the last? Page. The illustration is of the same slug of cable.
    Clearly now a museum piece.

    http://www.etf.ucg.ac.me/Obavjestenja/TernaWorkshop/Present and future innovations in the technology of submarine cables.pdf

  23. Second Opinion

    October 31, 2016 at 10:44 pm

    Try this. It’s on page 37 of 41
    Might take a while to load.

    http://tinyurl.com/zwownbf

  24. Pete Godfrey

    November 1, 2016 at 11:31 am

    Kelvin I came across a very interesting document on Submarine cables. It appears from my reading of the document that the cables have a lifespan of 25 years (guaranteed) to 40 years.
    It also appears that the steel wire armouring acts as a sacrificial anode. I have no idea why they would want that to be the case but that is what the excerpt below states.
    Maybe you will have more of an idea than I have, I would have thought that a PE coating over the whole cable would have been better. Then I am merely a lowly electrician with electronics experience.

    “The cables must be protected against the corrosive effects of the salty water and this issue must
    be seriously tackled by the cable industry. The primary protective layer against the salty water is
    the armouring which is composed of zinc-coated steel wires (Worzyk, 2009). The zinc layer around
    steel wires is 50 μm thick. The secondary protective layer consists of a bitumen sheath, which
    might be eroded or removed during the installation process or afterwards. It is replaced lately by
    an insulation sheath of high density polyethylene. The zinc and steel remain as main barrier against
    the salty water. Their decay rates in natural submarine environments are 1-50 μm/year for zinc
    and 10 μm/year for steel. Burying the cable in the sediment reduces the amount of water in
    contact with the cable lowering the corrosion. Experience showed that aluminium must be avoided
    as component in the armouring.”

  25. Richard Kopf

    November 1, 2016 at 2:48 pm

    The cable was ruptured by a breakdown of the insulation caused probably by lightning, or a fault in laying causing a minute leakage of water into the cable, or less likely a commutation fault.

  26. Richard Kopf

    November 4, 2016 at 9:03 pm

    Further to #25 I have had considerable experience in working with armoured cable supplying pumps and the like in the Cable tunnels in Melboune, at a time when much of Melbourne’s supply was 460v DC. Direct current, even at a low voltage in a damp environment, exploits the minutest flaw in a cable. I have seen cables displaying similar appearances to the Basslink cable, caused by internal rupturing of the paper insulation.

    This type of armoured cable was largely replaced with Pyrotenax mineral insulated cable in the 60’s.

  27. Simon Warriner

    November 5, 2016 at 11:14 am

    re 25, 26.

    Hilarious. I can see why you have chosen that nik, it is very apt.

    Clearly you know nothing about the rates of decay of a voltage spike in single core screened cables due to the capacitative effect, which lies behind the very reason the cable is DC in the first place.

    By the time your alleged voltage spike had reached the point of failure in the cable it would have decayed significantly which begs the question, what caused the cable to be so flawed at that point in comparison to elsewhere between the failure point and the shore station at which the lightning entered the system?

    The above point ignores the fault protection between the source of the lightning and the actual cable and the extremely high probability that any voltage spike great enough to do that damage at that location would have done very serious damage to the convertor transformer as well.

    You will of course provide the lightning strike detection records for the precise time of failure, which are required to support you conclusion, won’t you? They exist, I know because I have seen them used to confirm or disprove insurance claims for lightning damage on numerous occasions.

    My experience, for the record, includes repair of transformers up to 500,000 volts for high voltage links, through which such an alleged voltage spike would need to pass, training in failure analysis by EASA (Electrical Apparatus Service Association, the global body of electrical machine repairers) and a few weeks, early in my 33 year career repairing electrical machines and preventing them from failing in the first place, running 11,000 volt in the tunnels from Tokaanu Power Station to its switch yard. Oh, one other thing, I know the guy doing the investigation on behalf of the insurers personally, having worked with him and his associate on both investigation and recovery projects. I have absolutte confidence in his ability to find the cause. Faith in the ability of our government and its GBE to share that knowledge and admit fault if applicable is entirely another matter.

  28. Pete Godfrey

    November 5, 2016 at 1:45 pm

    #26 Richard if your scenario is right, that would mean that the insulation broke down, punched a hole in the Lead sheathing, then broke down the PE insulation around it before eventually shorting out.
    I am guessing that the protection system would monitor for leakage between the cable and lead sheath.
    Still it is odd that an obvious fault like that had to be inspected in England then also in Italy.
    I would have thought that there would be plenty of people here who could diagnose that fault.

  29. Richard Kopf

    November 5, 2016 at 8:53 pm

    re 27. yes I do know why the transmission is DC I also know that that the issues in relation to protecting DC transmission lines are not as well understood and developed as is the case for AC systems.

    Why fail at that precise point? A weakness in the cable most likely. Manufacturing techniques are not that precise that the dielectric strength of the insulation is equal throughout the full length of the cable.

    I also know that the TT popular theory that the Geelong Star hooked the cable could easily be disapproved and would have been known by now.

    So with your superior knowledge of electronics and access to very knowledgeable and infallible peers, what was the cause?

  30. Simon Warriner

    November 5, 2016 at 9:33 pm

    Dick, where is the data confirming lightning strikes in the immediate vicinity of either terminal? You don’t have any? Didn’t think so.

    It may be common among your professional colleagues to divulge commercially confidential information but I can assure you and anyone else reading this that I am in receipt of no such information regarding this matter, nor do I expect to be.

    Incidentally, what effect on the insulation integrity of the cable do you think an impact from the corner of a steel plate weighing a few hundred kilograms might be if it was being dragged behind a ship at trawling speed?

    By the way, nowhere did I claim a superior knowledge of electronics. Electrical machines perhaps, but not electronics. Someone with the background knowledge you are claiming should be able to recognise the difference, which tends to confirm what I have long expected, which is that you are a troll.

    Over, and out.

  31. Richard Kopf

    November 6, 2016 at 2:10 pm

    I started my electrical engineering profession as an apprentice “Armature winder and electrical fitter”, with Electric Motor Guarantee in South Melbourne in the 50’s then progressed to better things.

    What evidence do you have that the Geelong Star or any other ship was in the vicinity of the cable at the time of the failure? None of course. Is the pic really the cable or a file photo? Or was the cable further damaged when being retrieved, which is most likely.

  32. Pete Godfrey

    November 10, 2016 at 7:01 pm

    #32 Ian that site for lightning is pretty interesting. Pretty hard to see how it was a lightning strike if that map is accurate.
    Thanks

  33. Richard Kopf

    November 11, 2016 at 2:06 pm

    #32 As I said in #25 there are 3 options that could have caused the failure. It wasn’t the Geelong Star as it would not have taken this long to examine the log to determine if the ship was a suspect.

    Whatever the cause, ultimately water ingress occurred. Read this article which may enlighten you as to what the cause may have been.

    http://www.electricenergyonline.com/show_article.php?article=186

    There are some good photos of cables blown apart through internal faults.

  34. Richard Kopf

    November 14, 2016 at 1:43 pm

    #30. Simon. It is not my intention to spend $150 to obtain data about lightning strikes on that fateful day, in the proximity to Georgetown. If the experts can’t find the cause, it is not my intention to help….unless I am paid. Go to

    http://www.gpats.com.au/australian-real-time-feed

    open your wallet, then tell me that there was no lightning in the vicinity,(or perhaps there was?)

  35. Thomas

    April 9, 2017 at 12:02 am

    Pete, Kelvin,
    many of your assumptions on the cable components and their function are not correct.
    From where is the text in #24? My text book is cited there but wrongly.

  36. Kelvin Jones

    April 9, 2017 at 1:18 am

    Thomas #36 It would be interesting to know the exact performance of this cable.. Quality information would be appreciated.

    Since writing circumstantial information related to external trama by other another commentator in response to another TT article supports the scenario I outlined in the series. This was based on information from the fishing industry on how they operate.

  37. Pete Godfrey

    April 9, 2017 at 12:24 pm

    Submarine Power Cables: Design, Installation, Repair, Environmental Aspects
    Front Cover
    Thomas Worzyk
    Springer Science & Business Media, 11 Aug. 2009 – Technology & Engineering – 296 pages

    Hi Thomas, unfortunately I cannot find the article on my computer at the moment but this is the book the quote came from. I have had a hard drive failure since the TT article was printed and am still putting things back together.
    My information on the cable came from Basslink ( the cable construction), online articles (repair techniques) and personal work with Steel Wire Armoured cables.
    If you can be more specific as to where Kelvin and I are wrong we may be able to answer you.

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