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No Voltage on Wires in Light Switch

Discussion in 'Electrics UK' started by Jetheat, 22 Jan 2021.

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  1. Jetheat

    Jetheat

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    One of my 2-Way switches was intermitent and didn't work many times.

    Today, I opened it up and tested each wire with my multimeter for AC Voltage.

    No wire showed any voltage.

    Is there a fix for this or does it mean having to rip wires out the wall?

    JH
     
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  3. EFLImpudence

    EFLImpudence

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    Oh come on.

    It means find out why and rectify.

    Check the wiring at the other switch.
     
  4. EFLImpudence

    EFLImpudence

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  5. narkeybee

    narkeybee

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    You wont get voltage, meter measures difference between line and neutral or earth,it is not unusual to have only live in a lightswitch.
     
  6. Jetheat

    Jetheat

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    I hooked up the other light switch properly and its working.
    I also took the whole switch apart and separated all the wires in their own choc blocks but still no voltage at the other switch.

    So whether the first switch is connected or not connected, the other 2-way switch is still not showing any life.

    What do I do?
     
  7. ETAF

    ETAF

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    HOW did you measure, what wires, if there is NO earth and no Neutral, you are unlikely to see 240v AC
     
  8. Jetheat

    Jetheat

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    Right.

    On the none working switch, it's got 2 sets of wires.
    Each set has: Live (Brown), Switched Live (Grey) and Com (Black).
    So no Neutral.

    There's also an Earth wire connected to the back of the box.

    When testing, I put one probe on the Earth screw and the other touching all the wires in turn. But no result on the Multimeter.

    JH
     
  9. bernardgreen

    bernardgreen

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    Com is a label for a contact in the switch, The other labels will be L1 and L2

    LIVE should go to Com and Switched Live to either L1 or L2

    Inside the switch Com is connected to one of L1 in one position and L2 when the switch position is changed.
     
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  11. Jetheat

    Jetheat

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    The old switch had Live, C and X as labels on the switch.
    Black was in C.
    Brown in Live.
    Grey in X.

    I've tried to wire it up the same way on another switch with the same markings but still no voltage shown anywhere while hooked up.

    JH
     
  12. terryplumb

    terryplumb

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    Showing pics of wiring at both switches may be beneficial.
    Your two way switching , apparently,has a three core and earth cable between two switches.as one switch has voltage and works the light fitting ,and the other switch has no voltage on any of the three strappers ,that would indicate that the cable has been severed or there is a junction box somewhere with multiple
    disconnections.
     
  13. Taylortwocities

    Taylortwocities

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    Hmm. L, C and X…

    What sort of switch is this, exactly?

    As above, photos of the switch. Also mske and model will help.
     
  14. Jetheat

    Jetheat

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    Ok, I took these pics before I uninstalled the light switches.
    Both of them are 2-Gang and 2-Way.
    In the images, the Working Top and Working Bottom show the switch which is now working with my new smart switch.
    It shows 2 wires in each of the Live and X (switched live) terminals.

    The NotWorking image shows the other one where there is no voltage shown from any of the wires.

    JH
     

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  15. Jetheat

    Jetheat

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    That's my suspicion also.

    Is there a test I can do?

    JH
     
  16. terryplumb

    terryplumb

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    Are both the new two way switches dimmers ?
    Have you measured voltages to a known good earth ?
     
  17. Jetheat

    Jetheat

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    I've installed one so far with the new Lightwave switch and that lights up properly.

    I plan to do the same for the other other but no voltage.

    I'm using the only earth terminal in the back box. Is there another way to test it?
     
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