Fuse cover screw

I'd be surprised if it's anything other than a BA (British Association) thread as it was used almost exclusively for electrical equipment of that vintage. Guessing it'll be a 2BA or 4BA.

AWEM

Without being silly, will a blob of blue tack hold the cover on? I once used this to hold the door of a fire alarm panel in place, it worked very well.

Now where in the world would one find an old GPO telephone ...

Owain

I have literally dozens...

Yes, but I'd really rather not write "contrary to regs: bluetack" on my inspection form ;)

Or explain why it says that to my tenant...

JGH

I don't think the cover is required if you replace the rewirable fuses with retrofit MCBs. The slight issue with those retrofit MCBs is they are only rated 3kA breaking (verses 6kA breaking for most domestic MCBs). The very first retrofit MCBs for these boxes (with the two push buttons) were only rated 1kA breaking.

Make sure any unused positions are correctly blanked off.

Also need to check inside the fuse box for any overheating. These most commonly fail when the carrier contacts go poor, start overheating, and get worse, melting the cable insulation and causing the bakalite body/supports to fall apart. Can be worth retightening all the terminal screws too, but beware that parts of it are live, even when switched off, with high risk of arc-flash injuries (as well as electrocution).

If you fit an MCB instead of a fuse, then it doesn't have to be removed - ever - so it will hold in the cover quite safely (IMHO). Certainly it took a fair bit of effort to remove the MCB (which had been in situ for about 30 years) to check on the screw size.

I certainly fitted covers when I fitted MCBs. They were a Wylex standard part and came with the MCB. Just noticed that TLC still have them in their catalogue, so all is not lost.

Fair enough. I thought it may have been your own fuse box.

I will probably be able to get you one next week.

Pounder is wrong. The correct method is to use insulation tape:-)

The MCBs were designed so that if you smashed away the back of the the cover and refitted it then the MCBs could not be removed without removing the cover.

There must be a reason for that design.

I do try my best to be helpful. My name is Mr Pounder.

It seems to be a standard electrical outlet faceplate screw. Now, just need to find my tin of screws to find one long enough.

JGH