What Consumer unit should I get

[alabet1]

We recently moved into a 1940's property and I need to get installed the present one has only 3 circuits 1, Power for uptairs and downstairs sockets 2. Power for upstairs and downstairs lights (all are led) 3. New electric double oven. I need to have the consumer unit changed to a 4 circuit RCD so I can replace the gas hob with electric hob.

There is just enough space to add a new Consumer unit which I want to purchase before I instruct an electrician to save on cost, I have looked on various websites and I think the best option is to buy a British General fortress 6 module 4 way part poulated main switch consumer unit (854PV). or is there a better solution?

All the wiring looks like recent twin & earth why they did not add a new CU I do not know. We recently had new gas meter and electric meter for meter reading direct.

Alabet​

 

[oldbutnotdead]

Unwise.
Get a couple of electricians to quote for supply and fit.
And before you do that, make sure you allow enough circuits for future plans and eventualities (split upstairs and downstairs lighting, outside socket come straight to mind)
Be careful with your assumptions - the wiring you can see may be new, what about the wiring hidden in walls and floor- there could be all sorts in there

 

[securespark]

Yes, I would allow 20% for future expansion, I wouldn't fart about with RCDs, I'd have RCBOs and allow for a possible SPD.

If the board is too big for its current location, it shouldn't be a massive job to make the cupboard bigger or relocate to just outside the cupboard.

 

[Robin0577]

British General fortress 6 module 4 way part poulated main switch consumer unit (854PV). or is there a better solution?

Well, if you have to buy a budget beard, I suppose BG are better than some of the other cheapo options. Personally I would go for something a little more expensive such as Hager or Schneider.

4 way is unlikely to be enough for modern needs though, unless for a very tiny flat. You should consider surge protection as well, that will either occupy 2 spaces in the board, or could be fitted in a separate enclosure.

 

[ericmark]

The electrician selected should advise, not really sure how, as I am an electrician (retired) and am not fully convinced about need for a surge protection device (SPD) but just to be on safe side fitted one to my own house.

What we should do is measure the earth leakage, we are told back ground leakage should not exceed 9 mA, however if you use all RCBO's then unlikely you will have a problem, and it needs 4 modules less, so a smaller consumer unit.

Things do go wrong, and there have from time to time been recalls, the trade magazines and scheme providers tell the electricians, who are duty bound to come and connect any items they have supplied which have been recalled, and also replace any items which fail within the warranty time. To supply your own consumer unit means you loose these safe guards, so better to let the electrician supply and fit.

As to extras, well last house had 4 circuits to start with, sockets, cooker, immersion heater, and lights, I added a second fuse box, so had then 8 circuits, but really only needed one extra, this house I think 14, 3 x sockets lower, front and back, 3 lights lower, middle, top, cooker front kitchen, cooker back kitchen, one upper shower, and one lower shower, which leaves 4 not sure what they do, with yours it seems reasonable that at some point a car charging point may be added, and maybe solar panels, so an extra two seems reasonable, but no need to go daft.

Can't see any point using an old twin RCD box, the cost difference will be small, and what you want is should some thing happen to give you a shock and as a result trip the RCD you don't want to also loose lights.

All consumer units are type tested, which is why they are called consumer units not distribution units, and contain items to some British standard, so it seems to make little difference what make, we did go for the old favourites, with the idea one could get spares if required, but that now does not seem to be the case any more, with some manufacturers getting out of the domestic market.

So I fitted fuse box, it does the job, and was in stock at local suppliers, the only time when the more expensive ones make sense, is where you need some thing special, all items in a consumer unit need to be authorised for use in that unit by the manufacturer, or it will no longer be type tested, so if you want to fit a door bell transformer in it, then you can only use authorised types, and the more expensive tend to have more options.

 

[Murdochcat]

FWIW SPDs are mandatory now and fitting. 4 way CU would be foolish.

best get some local sparks to quote for a RCBO board

 

[JohnW2]

FWIW SPDs are mandatory ...

Nothing specific about an electrical installation is actually 'mandatory' - the only relevant law essentially saying that work done on a domestic installation must be done safely.

If you're talking about 'compliance with BS7671', then even in that sense, SPDs are not 'mandatory' if the owner of the installation makes an informed decision not to have them.

Given that one would have to scrape barrels pretty deeply to think of situations in which the absence of SPDs in domestic installations could be a 'safety' issue (risk to life or limb of human beings) it is questionable as to whether their being 'mandatory' could ever be justified.

Kind Regards, John

 

[ericmark]

SPDs are mandatory now

No, the default is to fit them, but the owner may reject their use. They protect appliances not personal so not mandatory. Personally I would say want some thing like this which would cost around £60.60 with 4 RCBO's at £9.90 each so £106.20 unless a TT installation if so would want twin pole RCBO's so £118.40, it may need an exterior isolator another £12, and also may need new tails, at £5 per meter, now we start to see the problem in the customer buying the parts, it may also need the DNO to fit the isolator anyway, and a simple error like not having two blanks could mean can't energise the unit until supplied.

The make the electrician normally uses he will likely have small parts in his tool box, but select another make, and you may need to supply every small part required.

The prices I have quoted found on the internet, great if you have the time to order, but find you want an extra bit, then looking for local supplier, then some thing like the isolator can easy cost £40. Also where I live to have to nip out to buy stuff can mean a 20 mile trip, so one cost of fuel, but also cost of paying an electrician to twiddle his fingers while you get it. Or worse him having to leave and return due to other work booked. Even next day means freezer defrosting.

 

[JohnW2]

.... unless a TT installation if so would want twin pole RCBO's

Just so that you could use the RCBOs for BS7671-compliant 'isolation'?

Kind Regards, John

 

[blup]

We recently moved into a 1940's property and I need to get installed the present one has only 3 circuits 1, Power for uptairs and downstairs sockets 2. Power for upstairs and downstairs lights (all are led) 3. New electric double oven. I need to have the consumer unit changed to a 4 circuit RCD so I can replace the gas hob with electric hob.

There is just enough space to add a new Consumer unit which I want to purchase before I instruct an electrician to save on cost, I have looked on various websites and I think the best option is to buy a British General fortress 6 module 4 way part poulated main switch consumer unit (854PV). or is there a better solution?

All the wiring looks like recent twin & earth why they did not add a new CU I do not know. We recently had new gas meter and electric meter for meter reading direct.

Alabet​

Get an EICR first, you may need a full or partial rewire. Let the sparkie recommend the CU, he will then be liable for any defects. He will also be comfortable with working on it. Good brands to watch out for: Wylex, Schneider, Fusebox, Hager, Crabtree. Fit rcbo’s not rcd/ Mcb’s.

Blue touch paper lit.

Blup

 

[ericmark]

I agree with @blup you want who ever does the job to take responsibility for it. As an electrician often I simply had to do as I was told, with a multimillion pound job so electrical engineer would design it, and some testing team would test it, all I did was fit items as told or laid out on some blue print. It was not my job to work out if it complied with BS 7671 although if blatant obvious an error had been made, I would point it out.

If you take on the responsibility as the designer, you must sign the paperwork as such, and using three signature installation certificates can't as far as I know be done under the scheme system, so work would need to be registered using the LABC, OK may be I am being a little pedantic, but if you read this forum you will see again and again where some one is asking what to do as electrician has not supplied the compliance certificate.

 

[Murdochcat]

Nothing specific about an electrical installation is actually 'mandatory' - the only relevant law essentially saying that work done on a domestic installation must be done safely.

If you're talking about 'compliance with BS7671', then even in that sense, SPDs are not 'mandatory' if the owner of the installation makes an informed decision not to have them.

Given that one would have to scrape barrels pretty deeply to think of situations in which the absence of SPDs in domestic installations could be a 'safety' issue (risk to life or limb of human beings) it is questionable as to whether their being 'mandatory' could ever be justified.

Kind Regards, John

given the state of the national grid these days anybody saving they don’t want an SPD is foolish

and AFDDs are heading this way very soon ….

 

[JohnW2]

given the state of the national grid these days anybody saving they don’t want an SPD is foolish

Maybe you know more than I do. I'm personally yet to be convinced that they would offer any useful, or 'cost-effective', benefit to me (or, indeed, to anyone other than those who manufacture and sell them). Put another way, if I had had SPDs in my installations for the last few decades ,I think the only difference would very probably have been the amount I had spent on the SPDs.

and AFDDs are heading this way very soon ….

You may well be right, and that may be equally 'questionable' - but at least (unlike SPDs) they theoretically relate to something that could be broadly described as 'safety'.

Kind Regards, John

 

[SUNRAY]

Maybe you know more than I do. I'm personally yet to be convinced that they would offer any useful, or 'cost-effective', benefit to me (or, indeed, to anyone other than those who manufacture and sell them). Put another way, if I had had SPDs in my installations for the last few decades ,I think the only difference would very probably have been the amount I had spent on the SPDs.

and AFDDs are heading this way very soon ….

You may well be right, and that may be equally 'questionable' - but at least (unlike SPDs) they theoretically relate to something that could be broadly described as 'safety'.

Kind Regards, John

Hmmm...

New consumer unit fitted in a small industrial unit after EICR, all AFDD. They have arc welder, MIG welder and TIG welder... guess which of those three trips the AFDD?

 

[robinbanks]

I want to purchase before I instruct an electrician to save on cost

How do you know it will?