Electricians....Help/advice please.

[tintin]

can any of you advise on a circuit plan please.
A friend has put up a large outbuilding on his farm, and has asked me to do some costing and planning for him!
The only part i'm not sure of is how many electric heaters i can plan , per breaker/circuit.
They will be cheap panel heaters(not storage) and are rated at 1500watts each.
As the building is being divided up into sections with different uses, it's very unlikely they will all be on at the same time and he only wants to spend the minimum on installations, BUT i'd rather plan/cost it as per proper reg's.
Any help greatly appreciated.
Thanks in advance
Alan

[Brummie]

The best advise I can give is DONT.
Unless you are a certified electrician.
It would be classed as a new instalation
and therefore must be wired to the latest regs.
If you go ahead and wire it for him get the instalation checked and certified as you would be held personally responcible if anything went wrong.The idea of an insurance company using you as a scape goat to avoid paying out doesn,t bear thinking about.
I,m a maintenance electrician and used to work on instalation years ago. but according to law now. I cant do work in my own home unless I have it tested by a "properly certified electrician"

[tintin]

PLEASE NOTE!

I am not doing any wiring here, my role is to plan/cost all the remaining jobs thru to the finished, ready to use building!
In order to price the electrics i need to know how many circuits and how big the consumer units will have to be!!
Hence the request.
Alan

[yoshie]

Blackpoolsparks is your man, send him a pm.

[Brummie]

Sorry about that. I jumped to the wrong conclusion and thought you were going to wire it yourself.

[blackpoolsparks]

can any of you advise on a circuit plan please.
A friend has put up a large outbuilding on his farm, and has asked me to do some costing and planning for him!
The only part i'm not sure of is how many electric heaters i can plan , per breaker/circuit.
They will be cheap panel heaters(not storage) and are rated at 1500watts each.
As the building is being divided up into sections with different uses, it's very unlikely they will all be on at the same time and he only wants to spend the minimum on installations, BUT i'd rather plan/cost it as per proper reg's.
Any help greatly appreciated.
Thanks in advance
Alan

First things first
What size (KVa or Amps) is the distribtion circuit to the new outbuilding? This is the first thing to establish before you start doing load calculations.

[tintin]

First things first
What size (KVa or Amps) is the distribtion circuit to the new outbuilding? This is the first thing to establish before you start doing load calculations.

Bugga!!

No idea! i'm only involved with the internals. All i can tell you is the incoming main will be an armoured cable from outside.
The sparks will have to make sure everything is big enough to carry what is being used!
Alan

[blackpoolsparks]

Bugga!!

No idea! i'm only involved with the internals. All i can tell you is the incoming main will be an armoured cable from outside.
The sparks will have to make sure everything is big enough to carry what is being used!
Alan

Wish I could answer your question with a simple post, unfortunatly its not that simple. There are a lot of factors to take into account when designing a distribution system. Load obviously is the starting point, your 1500w heaters draw 6.5 amps roughly. The size of the cable is dependant not only on the load, but also on the length of the cable run to account for voltage drop and also grouping factors and reference method.

Best thing to do is to get a sparks involved from the start, even if its for a quote. Make sure he is registered with either the NICEIC or ECA, all others are baically domestic installers. A good contractor will work with you if theres a job at the end of it.

If you want to run things by me , just send me a PM.

Please dont try to just "wing it", and Im not suggesting you would, but if you dont get it right the difference between the actual cost and the estimated cost can be significant.

[tintin]

Thanks BPS, much obliged for the details.
looks like i will have to allow 3 seperate cicuits in pricing , as i know
A) there will only be 6 X fused spurs (6 heaters) in this building
B ) the building consists of 5 bays and the first two will be seperated by a stud wall from the remaining 3.
C) there will only be 2 heaters in the 2 bay section and 4 in the other
The building is 16mtrs long and the seperating wall is 3/5ths of the distance from the consumer unit.

To conclude, if i allow 3 circuits for 2 heaters each, i then know how much cable and how many 'ways' the consumer unit needs!
Does that sound correct?

Thanks for your help dude!

Alan

PS cant get a sparks involved yet as he needs more money from the bank, and i dont want to involve subbies in pricing and calcs with the chance the bank may say no, so they will earn nought!

[blackpoolsparks]

Seriously Alan

get a sparks to look at it
The shed is outside of the main equipotential bonding zone of the incoming supply.

Dont take this the wrong way, but there are all sorts of things youre not considering.
The IEE Wiring Regulations BS7671:2008 are complex and you wouldnt be expected to know them.

[blackpoolsparks]

just saw your edit

dont worry about it, it happens all the time.
we are not bothered
we being responsibe electrical contractors that is

[tintin]

Thanks for the advice BPS, as i needed to crack on with the pricing i had to allow way too much money for the sparks side of the job!
Just hope he gets the money from the bank, hopefully theres about 3 weeks of carpentry for me there!

Alan