rcd
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incywincy
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Joined: Wed Feb 20, 2008 5:12 pm

rcd

by incywincy » Wed Feb 20, 2008 5:38 pm

We need a rcd installing in a house we have bought. We had a sparky round but he wanted to replace all the fuse board which is fairly new, it has Mcbs fitted. Is is possible to install a seperate rcd to protect all of the exsisting fuse board? Help!!

ericmark

by ericmark » Sat Feb 23, 2008 12:59 am

Think I have already answered this once but did not notice you have MCB's there are units called RCBO's that with some boards can replace the MCB's and give both over current and the protection given by RCB's
They are in many ways better as an earth fault on one circuit will not affect all the other circuits. They are expensive but by the time one includes the difference in labour costs you could fit 4 RCBO's for less than the price of a new consumer unit with one RCD fitted for all the protected circuits.
Two reasons for not fitting are:-
Some consumer units are not big enough for the longer RCBO to fit.
Some consumer units need double space for RCBO to fit so may require spare ways.
The very old wylex unit is completely unsuitable it needed mod to take MCB but no way will it take any RCD.
You say fairly new. If you have two spare ways you may be able to convert it to split board. And you may also be able to replace main incoming switch for a RCD but that in the same way as an exterior unit would require the main supply switching off or the incoming fuse being removed with would break the seal. But at £40 for a 12 way board with mcb's switch, and RCD included is it really worth it when a single RCBO can also cost £40?

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