Double insulated down lights cpc

[Alextrician]

whats classes as the correct method of terminating an earth cable when you have double insulated fittings?

You can see on the picture I can’t get a wage inside nor a normal connector block it’s just too tight.

I have seen in the past the cpc being bent over and also snipped off which isn’t recommend just wanted to know the correct way of termination.

 

[westward10]

As the cpc has been removed from the cable sheath which affords it protection then 521.10.1 would apply.

 

[westward10]

Interesting stuff, especially since i'm doing the 18th tomorrow.

The 4mm, if mechanically unprotected, rule is for "Protective conductors" the definition of protective conductors on P33 (BYB) does not mention CPCs but rather:-

"A conductor used for some measures of protection against electric shock and intended for connecting together any of the following:-
(i) Exposed conductive parts.
(ii)Extraneous conductive parts.
(iii)the main earthing terminal.
(iv)Earth electrode(S).
(v) The earthed point of the source, or an artificial neutral."

None of the above mentions or hints at CPCs.......

.....Except metal (none class II) accessories, which then makes the CPC a "protective conductor".


I think...

What do you suppose cpc stands for.

 

[GBDamo]

I'd still contend, that in the case of a CPC feeding a single luminaire, that it is not a "protective conductor" as the CPC is not linking Exposed Conductive Parts, if it were the CPC would be connected to the accessory, and therefore there is no requirement to enclose.

 

[Deleted account]

I'd still contend, that in the case of a CPC feeding a single luminaire, that it is not a "protective conductor" as the CPC is not linking Exposed Conductive Parts, if it were the CPC would be connected to the accessory, and therefore there is no requirement to enclose.

It's protecting the cable.

 

[GBDamo]

What do you suppose cpc stands for.

There are protective conductors and Protective Conductors.

Other than the instance highlighted above the CPC does not fit the definition on P33 and is not specifically listed as an example.

It is their for fault protection not electric shock protection.

So, as i read it, a CPC can be but is not always a protective conductor.

 

[GBDamo]

It's protecting the cable.

Not many cables suffer the effects of electric shock.

Joking aside, why would the BYB specifically define a Protective Conductor as "A conductor used for some measures of protection against electric shock....."if it means any old protective conductor?

 

[westward10]

What do you consider the purpose of a cpc.

 

[GBDamo]

As the cpc has been removed from the cable sheath which affords it protection then 521.10.1 would apply.

My initial comment said to over sheath, so we've got that one covered.

 

[westward10]

My initial comment said to over sheath, so we've got that one covered.

The conductor is still not enclosed for protection.

 

[GBDamo]

What do you consider the purpose of a cpc.

This is not an exercise in what I consider but what the book stipulates.

Please try to stick to the discussion rather than trying to undermine contributors.

 

[GBDamo]

The conductor is still not enclosed for protection.

Then no T&E CPC is, ever?

 

[westward10]

This is not an exercise in what I consider but what the book stipulates.

Please try to stick to the discussion rather than trying to undermine contributors.

Not what I am doing but you have stated the cpc is not a protective conductor although cpc stands for circuit protective conductor.

 

[GBDamo]

Not what I am doing but you have stated the cpc is not a protective conductor although cpc stands for circuit protective conductor.

No 'I' haven't. I have said that the book does not include CPCs as Protective conductors, and it is very specific as to what is does include.

Why does it not specifically refer to a CPC as a Protective Conductor?

 

[westward10]

No 'I' haven't. I have said that the book does not include CPCs as Protective conductors, and it is very specific as to what is does include.

Why does it not specifically refer to a CPC as a Protective Conductor?

You are looking for something which is not there, I could be incorrect but BS7671 does not use the abbreviation cpc. I believe it is only in the definitions in brackets after Circuit Protective Conductor.

 

[westward10]

Interesting stuff, especially since i'm doing the 18th tomorrow.

The 4mm, if mechanically unprotected, rule is for "Protective conductors" the definition of protective conductors on P33 (BYB) does not mention CPCs but rather:-

"A conductor used for some measures of protection against electric shock and intended for connecting together any of the following:-
(i) Exposed conductive parts.
(ii)Extraneous conductive parts.
(iii)the main earthing terminal.
(iv)Earth electrode(S).
(v) The earthed point of the source, or an artificial neutral."

None of the above mentions or hints at CPCs.......

.....Except metal (none class II) accessories, which then makes the CPC a "protective conductor".


I think...

A cpc is relevant to (i).