Non contact voltage indicator.....

[Wannabebetter]

I’m after a non contact voltage indicator that tests fairly low then up to 1000vac, I’ve seen this but wary of the price https://uk.rs-online.com/web/p/products/1611627/ any have one, or advise if I should steer clear of this one?

It’s not for proving dead as I know how to do that , it’s just for checking pipes before cutting them.

 

[bernardgreen]

or advise if I should steer clear of this one?

That will indicate the difference in potential difference between the person holding it and the metal it is close to. They do not indicate the absolute ( relative to Ground ) potential.

If the person is close to Live wires ( such as the cable to a light switch where there is no Neutral ) then capacitive coupling may induce a potential to the person's body. The indicator may then indicate Live when testing an Earthed piece of metal or wire. Worse it may not indicate when testing an item that is Live.

If you have the necessary two probe device for proving dead then use that as your voltage indicator. That is the safest way to avoid electric shocks.

 

[Wannabebetter]

If you have the necessary two probe device for proving dead then use that as your voltage indicator. That is the safest way to avoid electric shocks.

How do I use this then? One probe on pipe and the other on a known earth like a screw on a socket or switch faceplate?

 

[bernardgreen]

and the other on a known earth like a screw on a socket Yes

or switch faceplate? Not recommended

A switch, especially in older installations, may not have an Earth connected

 

[endecotp]

checking pipes before cutting them.

Do you mean metal pipes (conduit) with wires inside?

 

[Wannabebetter]

Do you mean metal pipes (conduit) with wires inside?

No gas and water pipes, also for removing gas meters. I have temporary continuity bonds for meter works, but we’re advised to test pipes before touching, thanks.

 

[Wannabebetter]

Thanks Bernard. What if the gas meter is remote from the house though?

 

[bernardgreen]

What if the gas meter is remote from the house though?

Reminds me of a gas meter reader who wore gloves after he got a shock from a meter. If there is no known Earth then I would consider using a small ground electrode to get a Ground potential as a reference potential.

 

[Wannabebetter]

If there is no known Earth then I would consider using a small ground electrode to get a Ground potential as a reference potential.

That’s great, thank you very much. Would something like this suffice? https://www.screwfix.com/p/earth-ro...swMdgew5gNfH84FV1MBoCX0QQAvD_BwE&gclsrc=aw.ds Also how far would I drive it into the ground? Presumably soil?

Edited: would I be able to test against the earth bonding that might be attached to the pipe?

 

[endecotp]

No gas and water pipes, also for removing gas meters. I have temporary continuity bonds for meter works, but we’re advised to test pipes before touching, thanks.

Unless this is an unusual environment e.g. electric railways or power stations, I suggest any regular non-contact voltage detector “pen”.

 

[Wannabebetter]

Unless this is an unusual environment e.g. electric railways or power stations, I suggest any regular non-contact voltage detector “pen”.

Thanks, so would the one i l8nked to be enough?

 

[endecotp]

Yes, I guess so.

 

[bernardgreen]

Edited: would I be able to test against the earth bonding that might be attached to the pipe?

No because it is connected to the pipe being tested, they will be at the same potential.

If there is a fault in the local electricity supply network ( broken Neutral ) then the Earth wiring in the house and all the bonded pipework, including gas pipes to the meter, could be a a potential much higher than the Ground you are standing on.

It was a disconnected Neutral in the electrical supply network that created the situation where the meter reader received an electric shock from touching the gas meter,.

The reason non contact testers can give false indications would not apply to someone standing on the ground and away from Live wires

 

[Wannabebetter]

The reason non contact testers can give false indications would not apply to someone standing on the ground and away from Live wires

Sorry, I got everything else, just couldn’t understand this? So at you now saying a ncvt is ok to use for me?

 

[bsr]

Not being funny, but if your employer is advising you test then shouldn't they be providing the gear? Our lads are not allowed to use their own.