Trailer Cable Core Failure





Results 1 to 10 of 10
  1. #1
    Join Date
    Mar 2012
    Location
    Randburg
    Age
    38
    Posts
    719
    Thanked: 1301

    Default Trailer Cable Core Failure

    I've come across this funny scenario with the camper NANO we built and was hoping somebody could shed some light(haha) on this matter.

    After our last trip we realised that one of the flickers wasn't working. Upon inspection we noticed that the core that goes to the one flicker was corroded and brittle, this now on the couplers side. Proceeded to trim back the 7core wire thinking that it might just be in the vicinity of the termination but after cutting back almost a 100mm the 1 core is still brittle and disintegrates while handling it, all the other cores are fine.

    Something is telling me that there is some sort of current leakage or something that broke down this core?
    Some feedback/Lesson would be greatly appreciated?
    GaryG

    4.0 XJ Jeep Cherokee - Go anywhere
    Honda Civic Type R
    - Daily Drive
    Isuzu KB 250 Xrider - Swambo
    Grand Cherokee WK2 Hemi - Sold


  2. #2
    Join Date
    Apr 2011
    Location
    Hartbeespoort
    Age
    45
    Posts
    197
    Thanked: 66

    Default Re: Trailer Cable Core Failure

    See if the core did not wear through somewhere and ended up arching to ground and therefore over current the circuit.
    However if that happened a fuse should have blown unless you have larger fuses in place than what is required.

  3. #3
    Join Date
    Nov 2015
    Location
    Edenvale
    Age
    55
    Posts
    1,117
    Thanked: 999

    Default Re: Trailer Cable Core Failure

    That sounds like damage due to heat. Must have a high current draw or the cable wasn't manufactured correctly.
    The humble person makes room for progress; the arrogant person believes theyíre already there.
    2004 Disco 2 Td5
    Suzuki SJ410 (being rebuild)
    VW Touran 2.0Tdi
    Lotus 7 (replica - not a kit)
    Freelance Photographer (part time)
    Member Of: Southern African Freelancers' Association

  4. #4
    Join Date
    Aug 2009
    Location
    Port Elizabeth
    Age
    57
    Posts
    1,051
    Thanked: 387

    Default Re: Trailer Cable Core Failure

    Copper wire embrittlement can only happen if you have a conductor made from a copper alloy or if the copper conductor was exposed to hydrogen.

    In your case most likely that wire was made from some scrap copper + copper alloy (brass, bronze) as source.
    Last edited by mygoggie; 2020/09/21 at 10:49 PM.

  5. #5
    Join Date
    Jan 2020
    Location
    Edenvale
    Age
    64
    Posts
    97
    Thanked: 43

    Default Re: Trailer Cable Core Failure

    This not uncommon I do electric fence installation and have found this to happen on some of the wiring that is used to connect via underground piping at gates etc. You have 3 or 4 cores running together and only 1 corrodes as you have mentioned. I use copper paste to arrest any sort of galvanic action happening yet it still happens. It seems as if it starts at one end and goes all the way tothe other end. Some times when it happens in two places it becomes difficult to find. Scientists might have an explanation why this happens but for us laymen it still poses a question. Youll have to replace and make sure all your joints are clean when you reconnect. Good luck.

  6. The Following User Says Thank You to Wylie E For This Useful Post:


  7. #6
    Join Date
    Aug 2009
    Location
    Port Elizabeth
    Age
    57
    Posts
    1,051
    Thanked: 387

    Default Re: Trailer Cable Core Failure

    Quote Originally Posted by Wylie E View Post
    This not uncommon I do electric fence installation and have found this to happen on some of the wiring that is used to connect via underground piping at gates etc. You have 3 or 4 cores running together and only 1 corrodes as you have mentioned. I use copper paste to arrest any sort of galvanic action happening yet it still happens. It seems as if it starts at one end and goes all the way tothe other end. Some times when it happens in two places it becomes difficult to find. Scientists might have an explanation why this happens but for us laymen it still poses a question. Youll have to replace and make sure all your joints are clean when you reconnect. Good luck.
    It is called galvanic reaction, the same principle that a battery cell works on. Basically it depends to what the copper is connected to. Say to stainless steel, then the copper will be eaten (the anode) and simply disappear.

    If you have an more noble alloyed copper connected to copper, then copper once again will be eaten away.

    If you have an alloyed copper connected to a more noble metal such as stainless steel 316, then the metals in the alloy that are less noble than the copper will be eaten out of the alloy (wire) faster than the copper itself and will leave the copper to appear brittle.

    The issue in SA is that most copper wires now come from China and there is no SABS control on these. So you have no idea what the source of the copper is and if the wires are in fact of ETP copper. Most likely these days it will not be.

    Here is a good chart showing the more noble metals at the bottom.


  8. The Following 4 Users Say Thank You to mygoggie For This Useful Post:


  9. #7
    Join Date
    Mar 2012
    Location
    Randburg
    Age
    38
    Posts
    719
    Thanked: 1301

    Default Re: Trailer Cable Core Failure

    So it's was quite a simple setup straight 7 core copper wire from coupler that has copper terminals but the body is galvanised straight through connected to the light.
    The 6 other cores are perfect and I can't see any wear on the cable sheath, it's only been a year.
    The effected core has basically become like a white brittle powder.
    GaryG

    4.0 XJ Jeep Cherokee - Go anywhere
    Honda Civic Type R
    - Daily Drive
    Isuzu KB 250 Xrider - Swambo
    Grand Cherokee WK2 Hemi - Sold


  10. #8
    Join Date
    Jan 2015
    Location
    Port Elizabeth
    Age
    57
    Posts
    185
    Thanked: 245

    Default Re: Trailer Cable Core Failure

    Quote Originally Posted by ViperR View Post
    ... a white brittle powder.
    Sounds more like aluminium wire. Copper will normally end up green as it oxidizes.
    Guy B. Vergoes Houwens
    2014 LC76 4.5 V8

  11. #9
    Join Date
    Mar 2008
    Location
    De Wildt
    Age
    58
    Posts
    39,178
    Thanked: 15571

    Default Re: Trailer Cable Core Failure

    You'll have to either strip the entire harness out or lay a new cable for that light from the trailer plug. There must be a short on that wire somewhere.
    Jakes Louw
    2012 Jeep Sahara Unlimited 3.6 V6
    Percivamus

  12. #10
    Join Date
    Aug 2009
    Location
    Port Elizabeth
    Age
    57
    Posts
    1,051
    Thanked: 387

    Default Re: Trailer Cable Core Failure

    Quote Originally Posted by ghouwens View Post
    Sounds more like aluminium wire. Copper will normally end up green as it oxidizes.
    Agree, copper goes black or green when oxidised. This sounds like aluminium bronze which looks like copper, but corrodes like alu.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •