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[bossr32]

my mate was watching tv it started to buzz whent off now none of the sockets work in that room ...funny thing is the rcd never triped...
can the rcd on the board blow like a fuse


all help greatfully needed.

[ericmark]

Sounds like a bad connection which needs finding and correcting.

[jimmy_one_ball]

RCD's won't detect overcurrent such as a short circuit or overload so no, they don't operate like a fuse, they merely detect earth faults and are used for additional protection only. The main fault protection is either the MCB's or the re-wirable fuses which must have tripped/blown because the other socket outlets don't work.

Is it possible there were too many things plugged in at the same time? For a 32A ring final circuit you don't want to go over about 7,500 watts, or if its a 20A radial final circuit then 4,500 watts. If this is the case then you will be able to re-set the MCB after things have cooled down a bit but it will soon heat up the cables again and the same thing will happen. Also a loose connection somewhere can cause this.

If you have a 16A breaker protecting a radial circuit then this may be nuisance tripping, simply replace it with a 20A.

If thats not the case then there must be a short circuit (fault in the wiring) somewhere but they usually go immediately and you can't re-set the MCB.

Might just be the TV is knackered, unplug it to see if the MCB can be re-set.

If you've got re-wireable fuses then make double sure you use the correct fuse wire! It's always best to get someone in.

Hope this helps

[ericmark]

[quote="jimmy_one_ball"]

If you have a 16A breaker protecting a radial circuit then this may be nuisance tripping, simply replace it with a 20A.

[/quote]
Do not change MCB type without having the circuit tested. When a rewire is done and the electrician has made a mistake and used too much cable one way around the problem is to use a smaller MCB. So to upgrade first the earth loop impedance would need measuring and the size of cable used will need checking it is not just a simple matter of changing it.

The description you give makes me think a wire has become loose. This in turn can cause a fire. So I would not recommend DIY repairs. With a ring main for a bad connection to result in loss of power you would need to have a second fault as well. If the ring is broken then the cable can over heat. So to prevent fire I would recommend not DIY'ing.