RCBO

[john4703]

I'm trying to think what would be the best way to replace my consumer unit. At present is is rewirable fuses and no RCD protection at all. There are little things that I dislike including the fact that all the outside power, sockets in the shed and outside lights are all simply connected to the 5A fuse that also serves the house lights.
I am aware that as we get older the ability to rewire a fuse will diminish (I'm feeling my age today ) and think that replacing the whole lot is a sensible way forward. I'd like to simply replace it with a consumer unit with one main switch and have every circuit on a RCBO, as I understand it that would give good protection and if there is a fault on one circuit the rest would still be fine. ----- Life was probably easier when I served my time and used 3/029 and 7/029 and rewirable fuses were state of the art. -----

I really want advice about my idea of having a RCBO for each circuit. Are there any real disadvantages in this?

 

[EFLImpudence]

The only disadvantages are cost and the slight difficulty that when one trips it is not known (unless obvious - bang) whether overload or earth leakage is the cause.

Oh and getting the neutral in or perhaps that's just me.

You could have a stock of old rewirables on hand to replace the blown ones.

 

[Iggifer]

I went with an all RCBO install a couple of years ago and would never go back.

Before I would have the odd trip every now and again, mostly because 6/8 circuits were protected by one RCD, and since I've had RCBO's - one trip, when a halogen lamp blew.

As EFLI almost said, lesser utilised circuits can trip without your knowledge, if you had a dedicated fridge/freezer circuit for example, or smokes, you wouldn't necessarily want those on an RCBO in case they tripped without your knowledge

 

[JohnW2]

As EFLI almost said, lesser utilised circuits can trip without your knowledge, if you had a dedicated fridge/freezer circuit for example, or smokes, you wouldn't necessarily want those on an RCBO in case they tripped without your knowledge

To my mind, the ideal is to have freezers and alarms on dedicated circuits (to prevent them being taken out by faults anywhere else), but to have power failure alarms on them.

Kind Regards, John

 

[securespark]

and rewirable fuses were state of the art

Nah, john....they were state of the art in 1882!

Even in the days of the 13th, breakers were in commonish use.

Stotz (Remember that name from early Wylex MCB's?) invented the miniature circuit breaker in the 20's.

The earliest circuit breaker predates our 1st Ed. and was invented by Edison for use on lighting circuits.

Obviously, even back then, people were hacked off changing the fuse wire!

 

[securespark]

To my mind, the ideal is to have freezers and alarms on dedicated circuits (to prevent them being taken out by faults anywhere else), but to have power failure alarms on them.

But that could create and awful lot of work and extra wiring and require a very large board....

 

[JohnW2]

To my mind, the ideal is to have freezers and alarms on dedicated circuits (to prevent them being taken out by faults anywhere else), but to have power failure alarms on them.

But that could create and awful lot of work and extra wiring and require a very large board....

I'm not sure how many freezers and/or alarms you're thinking of - many/most people probably only have one of each!

My point was that it appears that a fair number of people do put such things on dedicated circuits, to minimise the chances of their losing power, but thereby reduce the chances of early detection of a failure of one of those dedicated circuits itself - which can be overcome with a power failure alarm.

Or were you just teasing me (it is Friday evening!) by thinking I meant that, say, an alarm circuit should have a power failure alarm supplied by another dedicated circuit, and that 'alarm' circuit should have a power failure alarm supplied by another dedicated circuit, and that 'alarm' should have a power failure alarm .............? If so, I should perhaps have qualified 'power failure alarm' with 'battery powered'!!

Kind Regards, John

 

[john4703]

Nah, john....they were state of the art in 1882!

I think it was the firm I worked for back in the 60s that went for the cheapest option and that was rewirables I agree MCBs were around but I can remember rewiring some hefty fuses, (120 amp fuse wire is thick and heavy stuff).

I think I'll go for RCBOs except a couple of circuits, I'll leave a spare MCB for the freezer so if I ever rewire my kitchen it can be on its own circuit. The idea of having the freezer plugged into a twin socket and a battery powered no-volt alarm plugged into the other socket does appeal.

 

[JohnW2]

The idea of having the freezer plugged into a twin socket and a battery powered no-volt alarm plugged into the other socket does appeal.

Although I perhaps 'asked for trouble' by not including the word 'battery' when I first mentioned it, this is, as I said, what I do. I have also got a freezer temperature alarm (since freezers can, and do, develop faults even when they still have power!) - and, in fact, it is the temperature alarm, not the no-volts one, that has gone off 'in anger' a couple of times in the last couple of decades! The no-volts one has only ever operated when we have had power cuts, with a fairly obvious absence of electricity throughout the installation!

Kind Regards, John