PIR Sensor + Two core & earth (uninsulated)

[JohnW2]

So if you received a 29mA shock for god knows how long you'd walk away absolutely unharmed would you?

Maybe, maybe not. 29mA for even a short period would kill some people. The line had to be drawn somewhere, and the 30mA requirement for RCDs relates to the fact that a shock of 30mA or above carries a 'significant' risk of death - but a risk of death exists at less than 30mA in healthy people, and at a lot lower currents than that in those with certain diseases. Conversely, there's no guarantee that currents of 30mA (or a lot higher) will kill.

Kind Regards, John

 

[ban-all-sheds]

I'm afraid to say, more idle rhetoric from you.

I am beginning to feel that you are seriously hard of thinking.

If everybody had a full and genuine understanding of electrics, would this forum even exist, other than for the likes of egocentrics like yourself to go about congratulating yourselves on your immense knowledge of electrics??

If you really think that a belief by others that you should be competent to do electrical work before plunging in is a sign of egocentrism in them then I beg you to give up doing any more such work because you are barking mad and too f*****g thick.

Somebody else has already posed a similar question in this thread with regards to reappropriating the CPC for neutral, so clearly the answer is not as obvious as it may seem.

Many things are not, which is why you should learn about them.

EDIT: Having glanced about Google this is about the only mention I can find of earth not used as CPC. And contrary to what has already been said in this thread, says below you can resleeve the CPC of multicore cables.

And what does it say about thereby leaving the cable with no cpc?

To be clear, oversleeving non-insulated CPC is still not allowed.

Which is what you did.

 

[EFLImpudence]

Whith multicore cables such as flex, or SWA, it is allowed to oversleeve the exposed core another colour.

That is just a comment from someone - not the regulations.

What is it that makes that correct rather than that with which you seem to disagree?

 

[Iggifer]

Nevermind the fact that multicore flex and SWA don't have an exposed CPC like T+E

Also, I challenge you (norm360) to find an off the shelf 4 core SWA with a G/Y core

 

[norm360]

If you really think that a belief by others that you should be competent to do electrical work before plunging in is a sign of egocentrism in them then I beg you to give up doing any more such work because you are barking mad and too f*****g thick.

Showing your true colours now. You can't give any meaningful advice, only abuse.

Many things are not, which is why you should learn about them.

This forum is a place for asking questions and learning, haven't you grasped that concept yet?

And what does it say about thereby leaving the cable with no cpc?

You can quite plausibly leave a cable with no cpc for double insulated devices. It may not be good practice, but it is not against regulations. So you are wrong there.

 

[norm360]

Whith multicore cables such as flex, or SWA, it is allowed to oversleeve the exposed core another colour.

That is just a comment from someone - not the regulations.

What is it that makes that correct rather than that with which you seem to disagree?

The person in question was quoting the regulations.

 

[norm360]

Nevermind the fact that multicore flex and SWA don't have an exposed CPC like T+E

Once again, I already made clear it's not acceptable to oversleeve an exposed CPC like in T+E. But you can oversleeve with a different colour the insulated CPC of a multicore cable.

 

[RF Lighting]

But you have to supply EVERY point in fixed wiring with a CPC, so oversleeving the CPC is pointless as you'll have to oversleeve one of the other cores with green and yellow to supply the required CPC.

 

[norm360]

But you have to supply EVERY point in fixed wiring with a CPC, so oversleeving the CPC is pointless as you'll have to oversleeve one of the other cores with green and yellow to supply the required CPC.

Well there must be instances where it's done, otherwise why wouldn't the regs explicitly prohibit oversleeving the CPC in multicore cables?

514.4.2 "SINGLE CORE CABLES" that are coloured green and yellow throughout there length shall only be used as cpc and not over marked at their terminations.

 

[ban-all-sheds]

Showing your true colours now. You can't give any meaningful advice, only abuse.

B****y right I'll abuse you, SFB, given they way you are treating me. Maybe if you don't want people to abuse you you should not abuse them in the first place.

All I did was to say that I'd prefer it if people learned about things beforehand, and acquired a full and genuine understanding of how it worked and exactly what to do before they picked up a screwdriver, and you were so stupid or so unable to read it properly that you decided I was denigrating you.

Just for expressing a (IMO perfectly reasonable) preference that people should know what they are doing you decided I was belittling you.

When I had the effrontery to question that you then accused me of being egocentric.

This forum is a place for asking questions and learning, haven't you grasped that concept yet?

Indeed it is, but you seem to have failed to grasp that the best sequence of things is to ask questions and learn BEFORE doing something, not after.

In fact, you seem so resistant to that that you get bent out of shape when the concept is even mentioned.

Just what is so unreasonable about believing people should know what they are doing?

You can quite plausibly leave a cable with no cpc for double insulated devices. It may not be good practice, but it is not against regulations. So you are wrong there.

For fixed wiring?

 

[JohnW2]

Well there must be instances where it's done, otherwise why wouldn't the regs explicitly prohibit oversleeving the CPC in multicore cables?

Only a totally daft person would oversleeve the G/Y with some other colour and then oversleeve some other core with G/Y to act as the (required) CPC in fixed wiring! However, if they were that daft, what they'd done would be technically compliant with the regs - so it would be inappropriate to 'explicitly prohibit it'.

Kind Regards, John

 

[AdamCH]

514.4.2 "SINGLE CORE CABLES" that are coloured green and yellow throughout there length shall only be used as cpc and not over marked at their terminations.

Full version may be useful?

View media item 55583
Don't suppose they thought that anyone would consider using unsheathed earth as live!

 

[RF Lighting]

Well there must be instances where it's done, otherwise why wouldn't the regs explicitly prohibit oversleeving the CPC in multicore cables?

Maybe the item is supplied with an earth from another cable. You might need 8 switched lives, a neutral and an earth to some sort of indicator panel. That's 10 wires in total. You could run in two 5 core flexes, and sleeve one of the earth wires in one of the cables and still have a comlpiant installation.

What you can NOT do is omit the CPC from any point in the installation just because you want to use it for something else.

 

[JohnW2]

Don't suppose they thought that anyone would consider using unsheathed earth as live!

Yes they did, elsewhere in the regs - 'single insulated' live conductors are not allowed (outside of enclosures) - so a bare CPC, 'insulated' only by the cable sheath for most of its length, would not be allowed as a live (line or neutral) conductor.

Kind Regards, John

 

[JohnW2]

Maybe the item is supplied with an earth from another cable. You might need 8 switched lives, a neutral and an earth to some sort of indicator panel. That's 10 wires in total. You could run in two 5 core flexes, and sleeve one of the earth wires in one of the cables and still have a comlpiant installation.

Could you? ....

What you can NOT do is omit the CPC from any point in the installation just because you want to use it for something else.

Is there not also a requirement for every fixed wiring cable to have a CPC throughout its length (nails etc.), even if whatever is at the end is already getting a CPC connection from another cable?

Kind Regards, John