TYPE B, C etc RCBOs...
Author
Discussion

Sarah_W

Original Poster:

288 posts

202 months

Thursday 7th January 2010
quotequote all
I'm redoing my bathroom currently and got an electrician to fit spotligts last week. He upgraded an MCB to a type B RCBO on the fusebox and my dads just been looking over teh place and tells me that it should be fitted wiht a TYPE C

The guy I used was part P and has certified the work so I'm sure he's correct but my dads renovated a lot of places and is sure he's.

Who's right?

Smiler.

11,752 posts

252 months

Thursday 7th January 2010
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RCBO'S used to only be available with a type C characteristic (an RCBO is combined MCB+RCD).

Type C MCB's are common for lighting as the load may be inductive (fluorescent lamps, ELV incandescent & LED).

It depends upon the number of lamps & the load on the circuit.

What was the original MCB rating & type?

hairyben

8,516 posts

205 months

Friday 8th January 2010
quotequote all
Type B is general use and the norm for domestic, but either are suitable.

I've used type C's where you have lots of fluorescent lighting or GU10 downlights as the surge at switch-on can knock a type B out. Type C's are also less likely to trip when a lamp fails, but if there's a dimmer in circuit a type B is far more likely trip in time to protect it.