Electrical testing to find live wire

Discussion
1

Hello all!

I have some three wire lighting cord for a lamp and would like to splice in a toggle switch along the length for my lamp.

The toggle switch only requires that I splice in the live wire and the neutral & ground wires can bypass (remain contiguous through the switch body).

The braided exterior prevents me from determining which wire is which visually.

What would I use to detect the live wire? Do we have one of those in the space?

The cord will already be wired into the bulb socket and the mains plug, so it will be a functioning circuit.

Thanks! @electrotechs

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2

Assuming the wires separate when you untwist the cord, get them at least 100mm apart from each other and use a volt-stick to detect which is the live.
Also, where the plug is attached, are the three inner pvc sheaths brown, blue and green/yellow?
If you Google ‘volt stick’ you will find many. I don’t know if there’s one at SLMS, but there are at least two electricians regularly there who probably own them.
Otherwise I have one I can bring in tomorrow (Friday), or from Sunday onwards.

3

Thanks! I grabbed a cheap one online and will give it a go :folded_hands:

4

The other option would be to (with the lamp not plugged in!) use a multi meter and continuity test between the live pin and poke a needle into each wire at a time, technically leaves a pin hole in the insulation though :eyes:

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