Electricians/Builders - What Is This Cable?

[Deactivated] on 03/08/2022 - 22:25

Hi all,

I'm posting here hoping someone might help me understand something that I have never seen before.

Bit of a background, bought a house about 1 month ago. Tonight I noted that I couldn't turn on the lights in the laundry and thought that the light bulb broke. I took the glass cover down only to find it was filled with water. Looked inside the LED lightbulb, and it is completely filled with water.

So I took the light fixture down and saw some strange uninsulated wires (picture and picture). I opened the vent just above the laundry door to see if I can see anything and long behold, I see that cable going through the wood and into the wall.

This is the exterior where the cable should come out. I'm suspecting that it goes either to the upper floor or in the next room.

  • Turning the lights on/off didn't trip any fuses, which is a bit concerning.
  • The fixture is working, voltmeter shows 230V if I turn the lights on
  • I don't know if the wire is hot, I used a voltmeter, but it doesn't seem to get any reading. Also, I didn't open up the fixture to measure it against the negative wire.

It seems that there's another “extra” positive wire connected there, so there's definitely something shady going on.

Any suggestions would be appreciated.

Electrical & Electronics

Comments

  • holoz0r on 03/08/2022 - 22:42

    Could it be that they used that wire as their draw wire to bring the main cable in?

    • [Deactivated] on 03/08/2022 - 22:44

      That's what I'm thinking but then again, why so thick and made out of copper?

      • holoz0r on 03/08/2022 - 22:44

        Yeah, you definitely wouldn't want to use something conductive as a draw cable,typically why they use string or those nylon cable snake things. (I'm not a sparky)

  • FLICKIT on 03/08/2022 - 22:51
    +10

    It's an earth wire… Long ago, 50's?, a bare copper earth wire was run around to all the power-points, lights, and such, and then they just used an insulated 2-wire active/neutral… These days we use 3-core active/neutral/earth…

    • [Deactivated] on 03/08/2022 - 22:55

      The house was built in '75 so it is quite possible. I don't think the wiring has been redone since. Maybe it is time do redo it? Not sure how often the wiring needs to be redone.

      • FLICKIT on 03/08/2022 - 22:56
        +4

        Some history of Aussie wiring here:
        https://www.kennerelectrics.com.au/blog/electrical-cabling-h…

        • [Deactivated] on 03/08/2022 - 23:00

          Thank you for this. Interesting read. Had no idea about any of these.

          • FLICKIT on 03/08/2022 - 23:07
            +1

            @[Deactivated]: and as-per that, generally ~modern 70's white cable is ok, all the older stuff really needs to be replaced… (as soon as you touch or move the old black/rubber cables the insulation tends to breaks away)

            • [Deactivated] on 03/08/2022 - 23:11

              @FLICKIT: Thank you. I haven't seen any black/rubber cables in/around the hose but then again, I didn't replace any power outlets, I've had a look into one and had 3 white cables.

              I think my house falls well within this category

              Some older styles of TPS cabling are missing the earth wire so rely on a bare earth cable, which must be separately insulated if being terminated into a power outlet or light switch.

              • FLICKIT on 03/08/2022 - 23:13

                @[Deactivated]: You may have 3-core TPS going to all the powerpoints and then just the 2-wire and bare earth around the lights… I think long ago you didn't need to run an earth to lights, your place may have been wired around the time that changed maybe..

                • [Deactivated] on 03/08/2022 - 23:17

                  @FLICKIT: Is it odd that the fuse didn't trip when the wires were in the water and I turned the switch on/off multiple times?

                  • FLICKIT on 03/08/2022 - 23:22
                    +1

                    @[Deactivated]: Do you have safety switches?, they would probably trip… The plain old circuit breakers or fuses probably wouldn't trip, fresh water isn't very conductive really, it wont cause a direct short or get enough current flowing to trip a breaker.. ….

                    • [Deactivated] on 03/08/2022 - 23:31

                      @FLICKIT: Yes, the safety switch board is modern and it didn't trip.

                      At this stage I think I need to redo the pluming asap as my missus doesn't want to take a shower or wash her hands in the en suite which is just above the laundry if there is a possibility that water is leaking onto electric wires.

  • L8BLMR on 03/08/2022 - 23:14
    +2

    Earth cable. Old days before it was included in the newer style. Back then it was just bare.

    • [Deactivated] on 03/08/2022 - 23:17

      Thank you. It seems like it.

  • c64 on 03/08/2022 - 23:54
    +1

    you got 2 core cable + earth

    i'd be more worried about the water in the bulb …

  • Muzeeb on 04/08/2022 - 00:02
    +1

    Is the water in the bulb from laundry condensation eg. running a dryer without proper ventilation?

    LED bulbs are not as well sealed as the old incandescents (and don't need to be to function)

    • [Deactivated] on 04/08/2022 - 00:06

      No, the fixture was full of water as well. I think there were at least 300 - 400ml inside.

      I don't have a drier. But, in all honesty, I can't seem to figure out where it is coming from as there are no water marks near the fixture. There is a bit but not much at all and nothing that I noticed before. I think I need to take down part of the ceiling to check out where the water is leaking from.

      • Muzeeb on 04/08/2022 - 00:07

        bought a house about 1 month ago.

        What about the previous owners? It would take a while to collect that much condensation.

        • [Deactivated] on 04/08/2022 - 07:37
          +1

          No, I changed all of them to LED when I moved in as they were all incandescent.

  • websterp on 04/08/2022 - 07:56
    +1

    Many years ago they used two core and bare earth cables for house wiring in place of the fully insulated two core and earth flat cables currently in use. It was fully compliant back in the day so nothing wrong in coming across a bare earth lead in a house built in that era.

    What you should be really concerned about and take immediate action would be;
    1. Why no RCD or MCBs didn't trip.
    2. How water got inside the roof cavity and the globe.

    Perhaps check your earth is properly wired (grounded). Not a conclusive test and you won't be able to test the lighting circuitry but at least you can check if the earth leakage tripping is working on power circuits using on of these. If this cannot make a RCD trip when you press the test button get your house wiring checked by an electrician immediately.

  • dasa on 04/08/2022 - 09:24
    +2

    Earth cable as I have the same running through my walls.

  • the Unforgiven on 04/08/2022 - 19:40

    Gravity. Water would go down due to gravity, so you have to work backwards to find where the water came from, eg. trickled down. It is a very minor leak, so you just have to trace it back, then use heaps of silastic to plug up the hole, or something like that

  • ECE on 04/08/2022 - 19:42

    Old house. Soldered earth wire

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