Incoming mains fuse blown

[jupiter77]

What should I do if my incoming mains fuse blows? I heard a bang and there was smoke in the meter cabinet which is where the mains enters the property and contains the mains fuse, electricity meter and consumer unit.
None of the consumer unit breakers had tripped. I have manually switched the main breaker off as a precaution.
When it blew the TV was on, otherwise nothing out of the ordinary running.
Power is completely off no sounds or sign of further smoke or heat from the area.
Picture shows the area in question. There’s some scorching around black box bottom left.
It’s the middle of the night do I need to call someone right away or can I do it first thing in the morning?

 

[ericmark]

Quick google

If a DNO (Distribution Network Operator) main fuse blows, or you see a damaged fuse holder or exposed cables, you should stay away and call 105, the free-to-call electricity line. This service is available 24/7 from a landline or mobile to report these issues to your local electricity distributor.

 

[AndyPRK]

There is more than one fuse box off those brown and blue blocks. Maybe something off that has caused it.

Garage
Ev charger ?

 

[jupiter77]

Quick google

Thanks yes will be calling 105, was wondering if I need to call immediately or in the morning. I don’t believe there’s any immediate danger so will do it first thing

There is more than one fuse box off those brown and blue blocks. Maybe something off that has caused it.

Garage
Ev charger ?

There is an EV charger but it wasn’t in use at the time. Other one goes to the loft conversion I think. There is a breaker labelled garage but it’s always off as the garage was a prefab one taken down a few years ago.

 

[Murdochcat]

Main fuses can and do just flow through age BUT mainly there is a cause

So yes call out the network operator for your area and take it from there.

Please report back with what happens next

 

[ericmark]

I would hope fixed by now, wonder what happened?

 

[jupiter77]

I would hope fixed by now, wonder what happened?

They think the live and neutral on the incoming cable might have touched together, could have been a lot worse, fire etc.

Drive’s all been dug up old cable cut and a new length of swa cable connected and brought in to the house.

 

[Murdochcat]

Thanks for the update - so many posters never bother.

 

[JohnW2]

They think the live and neutral on the incoming cable might have touched together, could have been a lot worse, fire etc. ... Drive’s all been dug up old cable cut and a new length of swa cable connected and brought in to the house.

I don't really understand that suggestion. If there were an L-N short outside your house, that would be upstream of the fuse in your house, and therefore would not blow that fuse (or result in any excessive currents anywhere within your house)

 

[jupiter77]

I’m not sure but whatever happened it was inside the house. The fuse might not have blown but something went bang in the black box in the lower left corner of the picture in my first post.

 

[JohnW2]

I’m not sure but whatever happened it was inside the house. The fuse might not have blown but something went bang in the black box in the lower left corner of the picture in my first post.

Fair enough - but, as I said, if there was an L-N short outside your house, that should have had no effect on anything inside your house, fuse or otherwise. Are you certain that the bang was not outside?

 

[bernardgreen]

To me that looks like there was a short circuit where the insulation in the supply cable failed where it is clamped. The soot deposits suggest there may have been a small fire or arching in the supply cable before the conductors melted.

 

[jupiter77]

Fair enough - but, as I said, if there was an L-N short outside your house, that should have had no effect on anything inside your house, fuse or otherwise. Are you certain that the bang was not outside?

Definitely was inside heard it clearly there was smoke and everything. Now I think of it I remember them saying the clamp of one of the earth wires that’s been added, maybe when the ev charger was installed, might have been put on too tight.

 

[AndyPRK]

Do we reckon the old earth block has just been butted up against the cutout or is there a PME like connection ?

 

[Jurassicspark]

Do we reckon the old earth block has just been butted up against the cutout or is there a PME like connection ?

I doubt it’s meant to be TNCS.

Who knows?