Adding to circuits with no rcd (only mcb protection)

[electek]

Hi All,
I've got to add a Fused spur to a ring main for a supply to a boiler , however the ring main is only protected by a 32mcb and has no rcd protection. Because of this I assume I am unable to add the socket without updating the circuit.

I assume the best way would be to remove the MCB and fit an RCBO in its place. Would this be acceptable ?

Is it ok to make this modification and leave the rest of the CU as it is , obviously advising the customer that an upgrade is reccomended ?

Any advice appreciated.

Chris.

 

[m4tty]

Yeah I agree mate rcbo the cct. Cheers

 

[Des 56]

I dont think you require RCd protection

According to the Esc,a circuit not protected by an Rcd must have one fitted if you are adding a socket,unless it is surface mounted and designed for a spacific item of current using equipment such as a freezer

 

[Sintra]

RCD protection not required on old part of circuit. If your addition requires RCD protection then you can use a 30mA RCD FCU. Have a read here.

Alterations and Additions in Domestic and Similar Premises

If you put RCBO in at CU then you need to issue an EIC but if you use the 30ma RCD FCU then you use a MW cert.

 

[Guest123]

Seems Mr Mark Coles form the IEE disagrees with all but one of you gents, as he insists in his article in Wiring Matters magazine says that any circuit worked on must be brought in line with current regs.

Even though BS 7671 says only the added or altered aspect need comply.....

 

[Sintra]

Personally i would try and protect the complete circuit with an RCD / RCBO but sometimes it is not practicle to do so.

What issue No. is that in Lenny?

 

[Voltimax]

Mr Mark Coles has alot to answer for. Long haired lout.
Plus that is only the opinion of one man. Just because he works for the IET doesn't make him right. I have been given advice to the contrary by the IET tech line.

 

[Guest123]

What issue No. is that in Lenny?

Spring 2009 I believe.

 

[Guest123]

See attached PDF....

 

[m25maintenance]

if u add a socket u could put a rcd socket, but as 1 spark says if its dedicated dont worry, rcbo is ok as long as its same type of breaker as others, as u cant mix breakers

 

[ringer]

I dont think you require RCd protection

According to the Esc,a circuit not protected by an Rcd must have one fitted if you are adding a socket,unless it is surface mounted and designed for a spacific item of current using equipment such as a freezer

What is the thinking behind this, why would a socket for a freezer be exempted? What's to stop Mrs Hausfrau from unplugging the freezer to hoover the utility room, then plugging it back in when done?

 

[martysparky]

rcbo is ok as long as its same type of breaker as others, as u cant mix breakers

could you elaborate on that one please?

 

[martysparky]

What is the thinking behind this, why would a socket for a freezer be exempted? What's to stop Mrs Hausfrau from unplugging the freezer to hoover the utility room, then plugging it back in when done?

nothing....

apart from obvious reasons I think a cable buried or in a dry lining is unlikely to be more than 50mm from surface and thus require RCD but if surface mounted it is unlikely to be drilled through for example.

 

[ringer]

... What's to stop Mrs Hausfrau from unplugging the freezer to hoover the utility room, then plugging it back in when done?

(ringer answers own question...)

411.3.3(b) a specific labelled or otherwise suitably identified socket-outlet provided for connection of a particular item of equipment

 

[martysparky]

Good post with reg. I have wondered Where you get sockets outlet plates that say Freezer, TV, etc on them.. If you print your own label whats to stop someone removing it ir painting over it?

What is the usual / best practice for this guys?