Electrical question

switch it back on and keep your fingers crossed.

In message , Craig Cockburn wrote

It just as likely to be a spike on , or drop-out of, the supply into your house that caused the trip.

Do you mean the "boards fuse" (with the seal on where the electricity comes into the house), or a device (such as a RCD) in your consumer unit?

What had to be done to reset it?

It depends on which "main electric fuse" you mean.

It depends on the electrician involved, but we usually have more test gear and experience than the average householder.

John

Do you actually mean a fuse? Or is it an RCD? A sort of switch with a test button?

I guess this must mean the RCD rather than incomer fuse.

poor system design

if youre wiling to pay them enough

Single whole house RCDs are this problem just waiting to happen. There are some simple things you can do that will often fix the problem for now, but these installs are prone to this.

To check your appliances for a fault: get a multimeter and test from E to (L&N) on the plug of every appliance. Ones that conduct some are liable to trip that rcd. This isnt a perfect test, but will often locate one appliance that is the prime suspect, and its easy and cheap to do.

The real solution is to replace the whole house RCD with a better arrangement in the CU (fusebox).

NT

Maybe the OP has TT earthing and a whole house RCD (but labeled as "main switch") or an old ELCB. A mains spike external to the property could be responsible.

It was the main circuit on the consumer unit.

To reset it, I just push it down again, it's not sealed.

In message , "Dave Plowman (News)" writes

There's no test button.

In message , " snipped-for-privacy@gglz.com" writes

If it's of any help, the house was built in 1999.

There isn't normally a main breaker in a CU, unless it's an RCD with a test button (which you say in another post it isn't). A photo uploaded somewhere would help...

In message , Andrew Gabriel writes

It's a Wylex unit and compliant with 1991 regulations. The main circuit breaker switch which it the one that needed reset is a 100A fuse and is blue. There doesn't seem to be a test button

I've never come across a main circuit breaker that isn't an RCD. And if it goes down to switch on, sounds like a plain switch.

Any kids in the house?

Is it like any of these?

On Fri, 4 Aug 2006 09:03:42 +0100 someone who may be Craig Cockburn wrote this:-

I think you are confusing people with terminology that you don't really understand.

The main fuse is in a separate enclosure, which should be sealed with wire and lead seals. From that cables lead to the meter and from that another set of cables lead to the consumer unit.

In the consumer unit there will either be a main switch, or an RCD (which also acts as the main switch). Just to complicate matters a consumer unit may have one of both, separated by individual circuit fuses or MCBs. A main switch has two positions, on and off. It may well have 100A written on it, but that does not mean it has a 100A fuse inside. Rather it means, in simplistic terms, that is the maximum load that should be connected to it.

An RCD has a test button. It may also have a third position between on and off, tripped. This may also have 100A written on it, but that is for the same reasons as a main switch has 100A written on it.

The behaviour you have outlined is likely to have been because an RCD operated, but the description of the equipment does not tally with that. Until you can describe the equipment properly, or post a photograph somewhere, people will only be guessing about what has gone on.

ELCB is the only thing that fits the description given, but you wont find an ELCB in a house wired in 91 and built in 99 (??). Either show us a picture or theres really nothing can be done to help.

NT

The house was built in 1999 and wired up then. The relevant legislation referred to on the installation is 1991.

Due to the unit being in a small cupboard and on the side wall it's difficult to get a decent picture and the camera won't focus that close. However hopefully this will help

Craig Cockburn said the following on 04/08/2006 20:47:

See that white rectangle on the "100A Fuse" marked with a T?

That's the test button for the RCD. Try reading the sign written above that tells you all about it.

And you pushed the blue switch up to reset it, didn't you?

Pushed it down earlier. Perhaps that's why everything went out. ;-)

In message , "Dave Plowman (News)" writes

No, it went down itself. At 3am.