Electrical Question

Can the rcd simply be upgraded?

RCD trips when i use a larger power tool. the house was rewired some time ago, and has a Contactum box. i just moved in recently. the RCDs are marked 7110B, B10, which i believe is the rating. is it simply a matter of changing over the RCDs to ones with higher rating?

3 Answers

Best Answer

the mcb's/rcbo's are selected for a purpose by the system designer, generally a b10 is used on a lighting circuit and i would be left wondering why on a circuit where you plug in power tools.
An upgrade should require certification including compliance. The circuit involved at a minimum should be inspected and tested to be assured it is safe to uprate the breaker.
It is never advisable for people without the know how to be upgrading circuits as they would not have the experience/test equipment to do this without the possibility of overloading/overheating the circuit.

Answered 14th Feb 2012

kevin cassidy building contractors

Member since 16 Dec 2010

I suspect this is a MCB (minature circuit breaker) rather than an RCD. B10 refers to the it trip curve, B is domestic use and the 10 is the current rating i.e 10 Amps.

If this is a socket circuit then 10A is lower than usual, however before changing MCB's it is important to identify the cable size used as well as the type of circuit (ring or radial) to ensure the correct rating is used. It then needs testing with an Electrical Installation Certificate produced, if it is a domestic job building control also need to be notified.

In all honesty it is a job for an electrician and not a DIYer. It isn't a particulally big job so shouldn't cost the earth.

Hope that helps.

Regards, Allan

Answered 14th Feb 2012

Allan Lathan's Electrical Services

Member since 10 Aug 2010

The product you refer to is a minature circuit breaker not a RCD (see http://www.tlc-direct.co.uk/Products/CM7110B.html to confirm it is the same item). This circuit breaker has a maximum rating of 10amps and was presumably installed based upon the circuit design ie the maximum load & size of cable. If you were to install a larger rated minature circuit breaker you are changing the circuit design and could be overloading the circuit / cabling. So without carry out a visual inspection of the circuit it is not possible to say if the circuit could be upgraded to accomodate a larger load


CPJ electrics

Answered 14th Feb 2012

CPJ Electrics Limited

Member since 29 Nov 2011

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