Replacing fuses with MCBs - advice

[richdebc]

Hi, I've had a fuse blown on my consumer unit and thought it might be a good idea to replace them with plug-in MCBs. I think I've found the right ones to use, but would appreciate any advice from someone who knows what they're talking about (as I don't).

Thanks in advance.


My consumer unit:






MCB:

 

[pdcelec]

Although you could replace the fuses with mcb's, it looks like you need 7. It would probably work out cheaper to buy a new consumer unit. If you search around, you can get full units for £50 - £80.

 

[richdebc]

I had it in mind to just replace the 5A ones, as the others are protected by a RCD anyway - is this not a good idea?

Also, I'm not sure about replacing the consumer unit myself ,and reluctant to pay an electrician to do it if the existing unit's ok (it's only 7 years old)

 

[Adam_151]

Those MCBs are for a Wylex standard board like:

Not the type you have, you could get mcbs for yours if you wanted, and they'd look like:

But I see nothing wrong with leaving it as is, there is nothing wrong with cartridge fuses tbh, and as for the RCD issue, the rcd makes no odds, its job is different from mcbs, and I seriously doubt you want to swap the 5A fuses for MCBs, you'll have to reset the damn thing everytime a lamp fails

As for replaceing the whole lot, I see no reason to, you have RCD protection on your power circuits, and replaceing it is a job for an electrician or a *very* competant DIYer, and no offence to you, but I doubt you have the knowledge and test kit to do it safely

 

[richdebc]

Thanks to both of your for your help. And no offense taken - you're exactly right.

Although it would be a pain to reset the unit when an MCB switches off, surely less of a pain than replacing a fuse?

 

[Adam_151]

Although it would be a pain to reset the unit when an MCB switches off, surely less of a pain than replacing a fuse?

Yes, but MCBs are more likely to 'blow' than a fuse, with a fuse, there might be a rare occasion when a failing lamp takes it out, with a type B mcb, it'll happen just about every time

 

[richdebc]

Ah, I see. I've currently got a blown fuse from a bathroom spotlight, but if there's no real advantage to MCBs I'll just replace the fuse itself. Thanks!

 

[breezer]

mcb's will trip quicker than a fuse will, so tey are safer, but it is also cor conveiniance, click, back on again (really usefull in the dark)

 

[pdcelec]

It is a refreshing change to see someone on here ask a question, listen to the varying advice and make a sound judgement themselves based on the advice given.

 

[kai]

Another point worth noting, the MCB breaker costs about a fiver, but a replacement cartridge fuse costs a Pound each at BandQ.

It's no big deal flicking an MCB breaker back on after a lamp change, so it may be better to fit an MCB breaker on the lighting circuit, and avoid the cost and hassle of buying of replacement fuses.