Fixing a blown fuse on an old Consumer unit

[xeus]

Hi,

I've got an old consumer unit in my flat and the light fuse seems to have gone. Can anyone advise how to replace this fuse? Do I need an electrician? Hope not....

Attached photo of fuse box....

Any help appreciated......

 

[lectriclegs]

Pull down white fuse holder.

Remove fuse.

Put in new fuse.

Push fuse holder back in.

 

[JohnD]

FIRST

turn off the main switch. Don't pull or replace fuses with the power on. There will be a bit of a flash. Depending on load, it may damage the fuse connector prongs.

Modern breakers can be operated with power on, so this rule has faded from the collective memory.

For that type of CU, you have to buy a spare fuse (unless you already have some). It is not the same as the fuse in a plug. The size varies with current capacity. Like this

https://www.tlc-direct.co.uk/Main_I.../index.html#Spare_Fuse_for_C_and_NSC_Carriers

Buy two spare fuses, just in case there was a fault that is still present. If the new one blows, don't replace it until you or an electrician have found and fixed the fault. Light circuit fuses do occasionally blow when a filament lightbulb burns out, but with modern energy-saving lamps this is getting less common.

You can actually buy a breaker to exchange for your fuseholder at modest cost
https://www.tlc-direct.co.uk/Products/WYNHXB06.html
but you will need a competent electrician to fit it. There are live parts inside the CU even when you turn off its switches.

 

[ban-all-sheds]

I've got an old consumer unit in my flat

Owned or rented? (The flat, I mean)

the light fuse seems to have gone.

How do you know that?

Do I need an electrician?

Depends on what happens after you replace the fuse. Are you aware of any incident associated with it blowing?

 

[xeus]

Thanks everyone......

Got the fuse and lights are all back on.......

 

[ban-all-sheds]

So why did the fuse rupture in the first place?

 

[flameport]

A likely guess - one of those lamps which contain a halogen capsule inside a larger glass envelope, GU10 downlights/spots or often sold as 'energy saving' where you replace your old 100W for the 70W halogen equivalent.

Tiny capsule and 230V means filament failure always results in an internal arc to take out fuses and circuit breakers every time.

 

[ban-all-sheds]

Circuit breakers, yes.

But fuses?

 

[aptsys]

Circuit breakers, yes.

But fuses?

It's basically a short circuit until either the OPD acts or the plasma extinguishes. Even a cartridge fuse would probably activate first.

 

[bernardgreen]

Circuit breakers, yes.

But fuses?

Also Yes for fuses, once the plasma arc has started it will continue until the fuse ruptures or the capsule self destructs.
,

 

[ban-all-sheds]

Fairy nuff