Header fuse - changing

bossjohnc · Jun 12, 2013

Hi all, first post. Sorry to say I don't have much of a clue but I'd be grateful for some help.

My wife and I have just got our first house, it's a 1930s 3 bed semi. We've had a new board and pretty much complete rewire (lots of badly needed new chased outlets etc).

The electrician who did the installation mentioned that the header fuse was 60A, and that if I ever wanted to extend I should look at increasing the ampage, however I should check to see with the supplier if the cable coming to the building was safe to work with a higher ampage (i.e. 100A).

I'm not entirely sure who I should be contacting, as the supplier doesn't seem to have much of a clue and refers me back to my electrician. Also, I'm not sure where the header fuse is and whether I should be changing it myself.

Any advice would be very much appreciated.

Thanks,

John.

Engineer54 · Jun 13, 2013

oldtimer said:
Just watch Christmas day daughter just had a shower blowdrying her hair mum cooking the meal all electric son told to get off playstation and get a shower dad decides to help out and make a cup of tea and a slice of toast. :28:

And you'll still be lucky to see 50A for short periods of time!!

diabalo · Jun 13, 2013

If it adds to your confidence we have a 4 bed 34yr old bungalow, separate double garage, cooker, immersion, 8.5kW shower 17 light fittings, one or two portable heaters and a 2kW electric fire in the living for seasonal use, all the usual appliances and plenty of other equipment - all on a 60A main fuse. We bought up a couple of teenagers here too. We took advice when we had a new consumer unit and stuck with the current arrangement. A couple of years ago I bought one of those simple energy monitors to clamp on the meter tail. I've never seen it at more than about 12kW (around 52Amps) and then only for a very short time. Very useful gadget to see what the installation actually draws. I think the advice given here is certainly spot on with our experience.

Rockingit · Jun 13, 2013

You also need to remember that a 60A fuse will take quite a reasonable amount of overload before it actually pops, it'll stand several times over it's rated value for more than enough time to cope with the odd (unlikely) spike.

I've got a customer with a big 5 bed house, 12kW ground source system (50A), private water treatment plant (19A when pumping), workshop, enough lighting to satisfy the Blackpool mile, all the bells and whistles....... and they've only got a standard 80A incoming fuse. Admittedly, the DNO did have to upgrade their MV-LV pole TX as they were getting brown outs, but the fuse is quite happy!!

bossjohnc · Jun 13, 2013

telectrix said:
any chance of a photo?

Wow what a great forum, lots of replies - some of which do put my mind at rest a little. We'd be trying to get energy efficient lighting wherever possible, which should keep the draw down. If they can replace it for free though I won't stop them!

Here's a picture of the board, apart from the fuse box and meter (and the big switch) I've got very little idea what I'm looking at:

[ElectriciansForums.net] Header fuse - changing

telectrix · Jun 13, 2013

looks OK except for that BS951 clamp on the incomer's sheath. the "big switch" is an isolator so that the Consumer unit can be isolated without pulling the DNO fuse. breaking seals and all that.

bigbaddave · Jun 14, 2013

Murdoch said:
I would suggest you leave well alone unless you plan for 2 or 3 instant electric showers.

I know 5 bedroom houses running quite happily on 60A fuses and they have pools etc

My mates got a farm on a 60a fuse, One swimming pool, two houses, and 2x barns.. Has it ever blown.. Has is pap...

Dont worry my freind..

Guitarist · Jun 14, 2013

Any sticker anywhere stating when the next test and inspection is due?
As tel says, the main earth shouldn't be via that BS951 clamp. If you advise UKPN, they'll probably send someone round to sort that out FOC as it was like that when you moved in.

shocking_eg · Jun 14, 2013

bigbaddave said:
My mates got a farm on a 60a fuse, One swimming pool, two houses, and 2x barns.. Has it ever blown.. Has is pap...

Don'tworry my friend..

is there a nail in place of the fuse ?! lol

only joking, most 60A fuses hold out till 80/90A anyway