Live wire breakout adapter

fishkake · Jul 14, 2022

Hi there - some of you might have seen my previous post about current-measuring CT clamps. This is another question about them! Once again I'd like to make it clear that I am not an electrician; my understanding of what you guys do is more than a layman, but mostly conceptual rather than practical.

The clamps have to be attached to a live wire in order to power themselves and measure current. A lot of the support calls we receive are because people have put the clamps on to 3-core cables containing Live, Neutral and Earth, and of course they can't measure the current unless they're on a single live conductor (I say "of course" but I only learned this myself last week).

In a fuse box/CU etc. this is easy, as the live conductors are accessible. But say a user wants to measure the current flowing through a regular mains power lead, a C13 cable or something like that, to measure the current used by a printer or some other device - in order to do this, they would need to strip the external isolation, separate the live wire and attach the CT clamp to that. In the wrong hands (or even the right ones!) this could be dangerous, and maybe even illegal (I'm not sure about regs, I'm not a spark I'm afraid!).

Does some kind of adapter exist which safely and legally provides a breakout live wire, so customers could access the live wire without having to get a penknife out and violate various regs? I've drawn up an example of what I'd like (hey, I never said I was a graphic designer) - an adapter like this would let lowly IT staff install CT clamps on to any kettle-lead-powered device. My example shows a kettle lead, but it would be just as easy to do with figure-8 leads, or mickey-mouse leads, or any other standard cable.

I can't find anything resembling this, but it strikes me as the sort of adapter that might already exist. If anyone knows about a product like this, or an alternative, I'd love to hear about it.

Thanks peeps!

UNG · Jul 14, 2022

How about this

TIS 455 AC Line Splitter with Earth Leakage Measurement

Fantastic innovation to make current and earth leakage measurements on portable appliances.

www.testinstrumentsolutions.co.uk

Electro-tech · Jul 14, 2022

Great idea from UNG ! As you are into manufacturing maybe produce your own Adaptor with built-in CT.

UNG · Jul 14, 2022

I came across the line splitter a while back at an Elex and actually bought one to update my dodgy breakout flex it is a useful bit of kit and it does look more professional that the flex it replaced

RMS Electrical · Dec 24, 2022

fishkake said:
Hi there - some of you might have seen my previous post about current-measuring CT clamps. This is another question about them! Once again I'd like to make it clear that I am not an electrician; my understanding of what you guys do is more than a layman, but mostly conceptual rather than practical.

The clamps have to be attached to a live wire in order to power themselves and measure current. A lot of the support calls we receive are because people have put the clamps on to 3-core cables containing Live, Neutral and Earth, and of course they can't measure the current unless they're on a single live conductor (I say "of course" but I only learned this myself last week).

In a fuse box/CU etc. this is easy, as the live conductors are accessible. But say a user wants to measure the current flowing through a regular mains power lead, a C13 cable or something like that, to measure the current used by a printer or some other device - in order to do this, they would need to strip the external isolation, separate the live wire and attach the CT clamp to that. In the wrong hands (or even the right ones!) this could be dangerous, and maybe even illegal (I'm not sure about regs, I'm not a spark I'm afraid!).

Does some kind of adapter exist which safely and legally provides a breakout live wire, so customers could access the live wire without having to get a penknife out and violate various regs? I've drawn up an example of what I'd like (hey, I never said I was a graphic designer) - an adapter like this would let lowly IT staff install CT clamps on to any kettle-lead-powered device. My example shows a kettle lead, but it would be just as easy to do with figure-8 leads, or mickey-mouse leads, or any other standard cable.

I can't find anything resembling this, but it strikes me as the sort of adapter that might already exist. If anyone knows about a product like this, or an alternative, I'd love to hear about it.

Thanks peeps!

Fishcake
If you are not a spark leave it to someone who is qualified. A CT can be a collar-type with an opening or a solid ring-type. The former just slips over the conductor, but for the latter you need to disconnect the conductor and pass it through the ct ring. Always on the load side of an isolator!!
These operations are NOT FOR THE DIY-er!!
You have been warned
RMS