No CPC on the lighting circuit but the customer wants a metal fitting!!

[thwaitpd]

Hi i have been approached by a customer who wants a metal light fitting (obvious needs a cpc) but the wiring is from the 60s and they only installed twin L+N. If i run a CPC from a socket in the room up to the light fitting is this acceptable?

 

[Richard Burns]

The cpc should follow the route of the cable for which the cpc applies and would need to be 4mm if unprotected.
Best to run a cpc from the CU along the circuit to the fitting (and cover the light switch as well!)

 

[telectrix]

as above^^^ or you don't do the job.

 

[1shortcircuit]

Don't forget 30mA protection and Boding etc lol

What a load of effort for a bloomin light fitting... Soon see how much they like it when they look over your quote

 

[Octopus]

OR get them to look for a class II fitting - there are many now which can be fitting and look the part.

 

[Brightspark2]

OR get them to look for a class II fitting - there are many now which can be fitting and look the part.

Best option...

 

[Guitarist]

Although your job is not a CU change, maybe this will be of use to you...
http://www.esc.org.uk/fileadmin/user_upload/documents/industry/best_practice/BPG1v2_web.pdf

 

[Geoffsd]

It's a guide and contains absolutely ridiculous advice and suggestions.

 

[Blowcat]

Hi i have been approached by a customer who wants a metal light fitting (obvious needs a cpc) but the wiring is from the 60s and they only installed twin L+N. If i run a CPC from a socket in the room up to the light fitting is this acceptable?

The problem with doing it the way you have suggested, there is no R1 & R2 from the DB's lighting circuit to that metal fitting ( although it is earthed from the sockets). Best to run a seperate cpc or get a different fitting as others have said.

 

[Rauer]

So is that document saying that you can fit class 1 fittings without a CPc asking as an ir value over 1Mohm is achieved? And an RCd is fitted !!!

 

[Deleted member 9648]

So is that document saying that you can fit class 1 fittings without a CPc asking as an ir value over 1Mohm is achieved? And an RCd is fitted !!!

No, it's advising on a CU change where there is existing class 1 fittings and the client refuses to replace/rewire.

 

[Rauer]

Ok so say you do a cu change then are they saying that you can leave the class1 fittings fitted!!

 

[telectrix]

only if the fitting is not simultaneously accessible with earthed metal parts. personally , i would not like to use that argument in front of a judge and jury.

 

[Rauer]

only if the fitting is not simultaneously accessible with earthed metal parts. personally , i would not like to use that argument in front of a judge and jury.

No neither would I but I am trying to find a way to justify it in my head but I just can't seem to be able to!

 

[Engineer54]

No neither would I but I am trying to find a way to justify it in my head but I just can't seem to be able to!

There isn't any real justification of allowing Class1 lighting fittings on a Class11 circuit. This is just another cover all situation where an RCD is being used to replace a non-existent ADS. Seems even the powers at be, can so easily forget that RCD devices are supposed to be ''Additional'' Protection, and not a Primary protection on TN installations!!!