Converting 3 Story house from 3 phase to single phase

[Jjwet]

I recently purchased a 3 story house that used to be a care home but is now to be a family home with about 6 bedrooms. The distribution box in the cellar has An output of 3 large armoured cables, each phase going to a 12 unit distribution box on each floor. The electrician who has completed some outside work for me, tells me that to save me additional installation expense he can "blank off" 2 of the phases, remove 2 of the distribution boxes, wire between the floors and run the house off one phase.

I know very little about house electricity so my question is this - is this legal to run off one phase and more importantly, is it safe? His outside wiring appears sound and I am sure he knows what he is doing, but a friend told me that it was not a sensible thing to do and that 3 phase was safer.

Can a member advise which option is safer please?

Thanks.

 

[Rockingit]

Firstly, I can understand where the electrician is coming from. In a domestic situation there is very rarely a need for 3ph, and your friend is wrong in claiming it's safer - if anything it could be argued it could be more dangerous in a domestic dwelling.

Second; rather than just 'blank off' it will ne long-term cheaper for you to have your energy supplier down-grade the supply as they will be charging you for 3ph which is more expensive.

 

[malcolmsanford]

^^^^^^^^^^^^^^^ nail head hit , and concur entirely

 

[Jjwet]

Thanks Rockingit & Malcolmsanford. So is it best I get my provider to supply me with Single phase rather than get my electrician to modify my existing wiring? Would my service provider have to carry out any installation work or is it a case of switching from 3 to 1 phase at the power station?

My electrician has never mention that I should ask my provider to down grade my supply.

Thanks for your help.

 

[Rockingit]

Not sure exactly what they will do in the mechanical sense, that's up to them. In all likelihood they'll probably leave the incoming cable/s alone and just re-terminate them into a single-fuse head and fit a conventional meter as it's the least work. And they tell the computer to change your tariff!

Your electrician isn't allowed to touch anything which is theirs, he just fits your new wiring into the new meter.

 

[malcolmsanford]

The chances are you either have a 3 phase meter or 3 individual meters.

What I would do is contact your supplier be it British Gas, N-power etc and advise them what your doing. They will come along change or remove meters as is needed, and put you on a cheaper tariff.

It may cost a few pounds, but will work out cheaper in the long run. Also they should fit an isolator for you if required so that the electrician does not need to contact them again to shut the power off.

Just an aside, as you are having quite a substantial size home with 6 bedrooms, have you taken in your loading ie Electrical needs.

6 bedrooms how many on suite how many Electric instant showers?
How many bath rooms and again showers
Large house the 1 kitchen and if yes what are the cooking appliances Gas or electric
Heating gas or electric

Before you completely remove this supply have a word with the electrician about loading and what you require

 

[Jjwet]

Thank you both very much I am very grateful for your advice. I will contact Scottish Power tomorrow.

Kind regards.

 

[Rockingit]

You're welcome - it's what this forum is for! But do remember to keep your own electrician informed of what you're doing as it may affect parts of his design or thinking (and costs for work).

 

[Knobhead]

With 6 bedrooms it’s a sizable property with scope for more than one bathroom. Think carefully before making that call. If you decide on several electric showers, a hefty cooking range and all the ancillaries that go with a modern kitchen you could be pushing your luck with a single-phase supply. Sit down and go through things with your electrician and be realistic. As for what the electricity board will do if you go for the single-phase supply, will be to simply remove two of the service fuses and replace the meter. To change the service head just isn’t worth the time on their part. They should fit an isolator at the same time as doing the meter change.

 

[Rockingit]

With 6 bedrooms it’s a sizable property with scope for more than one bathroom. Think carefully before making that call. If you decide on several electric showers, a hefty cooking range and all the ancillaries that go with a modern kitchen you could be pushing your luck with a single-phase supply. Sit down and go through things with your electrician and be realistic.

Hence my comment to talk to the electrician first about their design.

It's true to say that I'm doing a domestic new-build at the moment and would kill for a 3ph supply but can't have one!

 

[kilmo]

i was in the exact same situation, bought a pub with 3 phase and am turning it into a 5-6 bed property. my electrician did the calculations and we could easily run on single phase, we also didnt want the risk of a potential 415v across light switches on the landing and the required warning signs etc

for the grand sum of £75 british gas came around and changed the 3 phase meter for a single phase and removed 2 of the fuses on the service head and sealed it. and fitted a dp isolator.