MCB tripped and will not reset (sorry, not RCD)

[willougs]

This morning, just after plugging in the iron, the power went off on a good percentage of the house sockets. The RCD in the CU has tripped, and attempts to reset it fail. The switch just seems to be "floppy" (as opposed to clicking back into the on position and tripping again).

Do RCD's fail? And if so, are they easy enough to replace assuming the main switch is off?

The consumer unit is a Hagar (?), the mains sockets are on two rings (other one still fine) and on the "RCD Protected" side of the CU.

Many thanks in advance.

 

[sparkwright]

Unplug the iron.

Push rcd switch down then up.

If still nothing unplug everything.
Push rcd down then up.
Plug things in one at a time.

 

[willougs]

Hi. Thanks for the fast reply! I have tried unplugging the iron and still no luck resetting. I will start to unplug as many things as I can find and let you know how it goes.

When you say "Push rcd switch down", you mean "further into the tripped position"? It's a toggle switch so after tripping, it is already in the down position.

Thanks again.

 

[sparkwright]

the mains sockets are on two rings (other one still fine) and on the "RCD Protected" side of the CU.

You sure it's an rcd, not an mcb?
What is written on the device you cannot reset?

 

[davelx]

Hi. Thanks for the fast reply! I have tried unplugging the iron and still no luck resetting. I will start to unplug as many things as I can find and let you know how it goes.

When you say "Push rcd switch down", you mean "further into the tripped position"? It's a toggle switch so after tripping, it is already in the down position.

Thanks again.

Yes - try to push it further down - if it moves, it should "click" and then you can push it back up all the way to reset. Some RCDs work like that and it's not immediately apparent visually. so give it a try.

 

[willougs]

Sorry, it probably is an MCB. It's got:

"Hager B32 230/400V MT132"

Pretty similar to this:

Apologies... not really up on electrics as you can probably tell.

The wife has gone around unplugging as much as possible and still no reset.

 

[sparkwright]

Isolate any outdoor electrics and central heating that may be connected to the circuit.

Hopefully the power will stay on when everything is unplugged/disconnected.

As you start putting things back if the power goes off you can identify what may be causing the fault.

 

[willougs]

Ok. Thanks very much for your help. I'm at work at present and the wife has assured me that everything is unplugged but it still will not reset. Don't think we have any outdoor electrics.

I'll have to give it a once over when I get home tonight.

Thanks again. Very much appreciated.

 

[1john]

Does it 'pop' when you try to reset it, or is it not latching properly?

 

[willougs]

Does it 'pop' when you try to reset it, or is it not latching properly?

No, doesn't seem to pop when resetting. It doesn't seem to latch at all... the grey toggle switch just feels "floppy" (for want of a better word).

 

[sparkwright]

Can you get the mcb switch to go up when the big main switch of the cu is in the 'off' position?

 

[willougs]

Can you get the mcb switch to go up when the big main switch of the cu is in the 'off' position?

I'll get the wife to try that in a second. By "big main switch", is that the switch on the far left marked "RCD protected circuit"? Or the big switch on the far right? Or both?

The CU seems to be split into two. On the left is the mains sockets, cooker etc, and on the right is things like (from memory) burglar alarm.

There's basically two larger switches at each end of the CU both marked "WARNING: Live connections"

 

[willougs]

With the left hand main switch (which feeds this MCB) in the off position, the MCB will still not reset.

 

[JohnD]

if it will not reset when there is no power to it, it is faulty. You need a new one. Be sure to fit the genuine maker's part with teh same part no as any other may not fit correctly. If you are competent and capable to do it yourself, turn off the main switch before you remove any covers, and keep clear of the incoming cables and their terminals on the main switch, which will be live even when turned off. When fitting and MCB, undo the screws on the new one to their fullest extent (it is possible to mis-fit them if this is not done) and only start to tighten them when the prong and the cable are fully inserted. If you look at the new one you will see how the retaining clip is released.

If you need a temporary fix, it is possible to swap a similar MCB from within the enclosure, if it happens to feed a less important circuit.

There will be an electrical wholesaler in your town who will probably have the part in stock, or get it within a day, he may be tucked away down some back lane in an industrial estate, try the yellow pages. It will cost you about a fiver so you might buy a spare for next time, though they are very reliable, it might be obsolete next time you want one.

 

[willougs]

Hi John. Thanks very much for your reply. Hopefully the MCB is the problem. I'm a bit of a baby when it comes to electricity so I will have arranged for an electrician to come around this afternoon. After a brief chat on the phone he is under the impression that the MCB will be the fault too.

I do like the idea of getting a spare couple of MCBs, as I assume as time goes on, they may become harder to find for our specific CU.

As a matter of interest, I see you are in Hampshire... which part?