Consumer unit question.

[GAjon]

I have a Memera 2000 AD consumer unit with rcd trip switches.
My son was working in the garage today he plugged in an inspection lamp, on a standard 3 pin plug, the lamp bulb blew and tripped the garage sockets circuit.
The problem is the trip switch goes back into the on position but all the sockets are still dead.
We've done a full reset of the unit,
Changed the face of the double front socket that the lamp was plugged in to in case that had been damaged.
Made sure all other electrics are off and tried a reset, but still to no avail.

So the question is, could the circuit rcd have failed?
Can I replace just the one?
Is it time for a new consumer unit, it's probably 15 years old.
Should I grab a beer and call an electrician tomorrow?

[Welshbeef]

There is never a bad time for a beer.

But yes have one then reassess with a clear head and a sparky.

[hairyben]

iirc MEM rcd is weird design which trips to halfway position and needs switching off then on to re latch which catches people out,tried that?

[Alucidnation]

Not much can be diagnosed on the internet, without getting hands on.

However, is this cu in the garage, independent from the house cu?

If so, check the house cu that the feed for the garage is still on.

Or, post up a pic.

Edited by Alucidnation on Wednesday 19th July 20:22

[505diff]

Have you pushed the RCD switch all the way down before lifting it back up?

[Alucidnation]

The RCD wouldn't normally hold in the on position if it wasn't reset..

[GAjon]

This is the unit, sorry if image is inverted.

Garage Socket circuit is in off position as is cooker circuit, unrelated reason.

Think I've tried all reset options and no change.

This unit is the only one and us fed direct from the mains incomer.

Thanks for replies so far, the beer fridge is on a different circuit so not a complete tradgedy.

[Alucidnation]

I take it you have switched off the MCB for the garage sockets?

[GAjon]

Alucidnation said:

I take it you have switched off the MCB for the garage sockets?

Yes that's correct, I didn't want to leave it in the on position with a possible fault.

[Alucidnation]

Good.

I suggest, opening fridge, remove beer & enjoy.

Call your local sparky in the morning as it will need properly investigating.

Keep us updated!

[DanGPR]

From the look of the CCU, the one RCD covers the whole board (or at least half of it). If the RCD was faulty none of the circuits covered by it would be working, not just one.

It's possible that the MCB is faulty, or whatever it was that caused the trip has damaged the cable enough to cause loss of continuity to either the line or neutral conductors. You'll struggle to find the fault without at least a very basic multimeter/probe tester.

I'm assuming it is only the garage circuit that is currently dead?

[GAjon]

Thanks Dangpr, so it is possible for the circuit mcb to fail after a fault.

Does the mcb not offer the cable some protection from damage?

On further investigation, I was out when this happened, the bulb didn't just pop, it went with a loud bang so could have been enough to cause damage.

Yes, only the garage socket circuit affected.

Thanks.

[stevensdrs]

Does the garage have lighting as well as sockets and is the lighting working.? Is there a secondary fuse box in the garage? There is in mine with an MCB for 5A lights and 13A sockets.

[GAjon]

The lights are seperate, it's only the garage sockets affected.

My now lager enhanced logic is telling me if it was the wiring or any other component of the system the mcb would re trip after resetting, it's not, it stays in the on position with the circuit dead, so it must be the mcb!

Or mrs plumb in the library with the hammer!

[hairyben]

Not a fused spur on the line to the garage is there? Popping bulb can knock out a 13a fuse.

[CorradoTDI]

Can you confirm the lights are on a different circuit?

If not I'd suspect another fuse box or at least a fused connection unit as stated above.

Sure there isn't a box hidden behind boxes or shelving that you've forgotten about?

[GAjon]

Yep, the lights are on a different circuit, I've gone through switching the other mcb s off and seeing what happens.

Definitely no other fuse boards or rcd units.
All other electrics are working a ok.

I've ordered a replacement mcb for the one I think is faulty and am going to replace that as a starter.

[8.4L 154]

If your competent/confident enough to take the front off to swap out the MCB with the one you have ordered then I'd first have stuck a multimeter on the MCB that's there which would have told you if the MCB or Wiring is at fault.

[GAjon]

8.4L 154 said:

If your competent/confident enough to take the front off to swap out the MCB with the one you have ordered then I'd first have stuck a multimeter on the MCB that's there which would have told you if the MCB or Wiring is at fault.

Right, will do.
It's a weekend job, I've got to move cars about to get decent access to do the job.
Thought I'd get the unit first for the sake of a few quid.

[GAjon]

All done, MCB changed and all working fine.

I am now suspecting, as this is the garage sockets only, because I run my welding set in there I may have been overloading the MCB ( i made a new roll hoop earlier this year so was doing quite a bit of welding).

A seperate supply for the welder might be a good plan.