Old Consumer Unit…..

[Jonathon59]

Hi,
I have an old consumer unit-complete with pot fuses and requisite fuse wires within-which was probably last updated when our house was re-wired in the 70’s.
I’m only guessing the approximate date for the re-wire as it was before we moved in over 40 years ago and no documentation was available when we moved in-health and safety not being much of a ‘thing’ back then! .
The box has a separate breaker which used to ‘trip’ occasionally but has now stopped ,so blowing a fuse requiring the wire to be replaced, although if I throw the switch myself it cuts the electricity to the house.
Has anyone else had a similar problem?
Thanks in advance.

 

[blup]

For around £7/800 the problem will be solved with a new CU.

 

[securespark]

Yes, the board is well past its best. And possibly the wiring too, dependant on its installation date: might there be rubber cable installed or lighting circuits without earth conductors?

You say it was rewired in the 70s, but can you be sure of this?

 

[flameport]

The box has a separate breaker which used to ‘trip’ occasionally but has now stopped

A large blank clunking thing with a round red or yellow button?
Or an equally large grey affair with a large rectangular yellow button?

 

[Murdochcat]

You need to get 2 or 3 local sparks via recommendation to come and take a look to offer their opinions

As it stands you really need to get the unit upgraded to a RCBO board with SPD

 

[ericmark]

I assume @flameport is thinking same as me, the trip of that age maybe an ELCB-v today we use ELCB-c better known as RCD's.

The problem with an ELCB-v is earth bonding can stop them working.

As to the fuse it depends on make, the old Wylex can be replaced with MCB's but not sure about other makes, but the ELCB-v was fitted to TT systems, which means an earth rod is used, and so a short to earth could completely fail to rupture or trip anything.

In real terms the cure is to replace fuse box with a consumer unit, however if it use to trip, then likely there are faults, and you need to find these or you will not be able to turn the power on.

I don't like saying get an electrician, but in this case that does seem the best option.

 

[Adam_151]

A large blank clunking thing with a round red or yellow button?
Or an equally large grey affair with a large rectangular yellow button?

Ah, stop being so pessimistic, it might not be a VOELCB, it could be grey, in a dark grey enclosure/cover which screws into the drive top and bottom with massivly oversize sized poorly created cable entries through which you can see the terminals* and have a small white test button, and the ON legend in red lettering

*That seemed to be the de facto way to install them.....