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Testing voltage on telephone poles

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Junior Member level 1
Jun 9, 2022
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Hello I was running fibre on some telephone poles and touched the messenger and got a shock. It Wasn't huge but definitely noticeable. I'm in an insulated bucket though so it could've only traveled through fingers. So I wanted the ability to check for voltage on the messenger line. So I got a ncv pen but it doesn't tell me anything useful. You can get a reading 6ft away from a dead messenger. Likely due to the transformers/current going through the mains.

Just wanted to be clear on my terms and what the poles are like here in Canada.

the messenger is a steel wire to support data lines. (fiber and copper). It is connected to earth every few poles.

The nuetral is at least 1m above the data lines, although a few poles from where I got a shock the nuetral appears to be touching the messenger.

The primary is above the nuetral.

So what do people use to test this? Will a clamp meter do what I need to keep me safe?

'Telephone' pole ... 'power' pole... Whatever it is, needs to measure at a pole that has a good ground connection as reference for a voltmeter probe when measuring your 'messenger' support.
Telephony circuits are 50 VDC, and can be noticeable touching with sweaty hands. Telephone while ringing is 90VAC 20Hz , for sure noticeable at touch. Cable TV signals use a booster powered by usually 24V, unlikely to be that much noticeable. Find the problem !

But if I measure at a pole where it's grounded to earth wouldn't it have to be 0v? Or 0v + whatever VD is just down the copper grounding line which would be near 0?

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