allowed supply 1 room with 2 circuits from 2 consumer units ?

jaya

when adding a mini consumer unit for a new room , can you add a supply to an existing room from the new consumer unit

the old existing room would then be supplied by
2 consumer units -
supplying 2 seperate radial circuits
and 2 seperate lighting circuits (1 way switched)

is this against regs, unsafe and not recommended, or allowed ?

2011

It is permitted and is frequently done. For example in industrial installations equipment packages would often have a dedicated distribution board and / or control panel. Packages can cover very large areas that would have services such as HVAC, lighting and general services which would be supplied from different distribution boards or even from different switch rooms or substations.

However I would guess that you are dealing with a domestic installation. My preference with domestic is just to have one distribution board serving the main house. Maybe in your circumstance this is not practical.

jaya

ty for your reply 2011

my (REC) electrician told me adding 1 socket or 1 light or 1 light switch to an old adjoining room (while wiring a new room) was against regulations and would require the old adjoining room to be totally rewired, all sockets, lights, switches

i found this hard to believe

Jim.s

It.would.be bad practice at.the least for domestic work

Everything would.need.to be very clearly labelled

Not.sure if there's a regulation

Jim.s

Inthe domestic the householder is switching off power and may get mixed up

2011

Jim.s wrote: »

It.would.be bad practice at.the least for domestic work

I'm not a fan, as above I prefer not to install a sub board in a house.

Everything would.need.to be very clearly labelled

This is already a requirement.

Inthe domestic the householder is switching off power and may get mixed up

Unfortunately there is always a risk in any installation that someone may not isolate the correct circuit. This can even happen when everything is clearly labeled and what is fed from where is made as obvious as possible. When isolating no assumptions should ever be made. It is the old rule "isolate, test and try".

Jim.s

Not that easy to clearly label a board feeding 1 light and socket and another board feeding a second light and socket in the same room

My other point is that in industrial for example you have trained personnel doing the isolating and locking off

Jim.s

A sub board is also often a requirement in a house

Doesn't.look much like it here though

2011

Jim.s wrote: »

Not that easy to clearly label a board feeding 1 light and socket and another board feeding a second light and socket in the same room

It is easy to put a warning label on each board stating exactly that.

My other point is that in industrial for example you have trained personnel doing the isolating and locking off

Very true but it was just an example for the OP. The question was about what the regulations permit. The risks of this approach is another matter.

Jim.s wrote: »

A sub board is also often a requirement in a house

Yes. I rather avoid it in the main house though.

jaya

ty Jim.s

what would be the situation if there was only 1 consumer unit? the old room would then have
1 consumer unit - supplying 1 room with -
2 seperate radial circuits
and 2 seperate lighting circuits (1 way switched)

is this bad practice again, or is it as bad ?

is the potential confusion by a domestic user caused by the sub board or the seperate mcbs for 1 room

2011

jaya wrote: »

what would be the situation if there was only 1 consumer unit?

Much better job.

the old room would then have
1 consumer unit - supplying 1 room with -
2 seperate radial circuits
and 2 seperate lighting circuits (1 way switched)

is this bad practice again, or is it as bad ?

It’s very normal (and good) practice that can be seen in domestic installations all across Ireland.

is the potential confusion by a domestic user caused by the sub board or the seperate mcbs for 1 room

There is always a risk that someone will isolate the wrong circuit no matter what way the wiring is installed. Nothing can remove the risk 100%.