One for the electrical boys, please ...

Arfa Daily · 2011-04-13T16:20:06+00:00

We are in the process of taking some modern commercial premises, in which the landlord is dividing down a 2k sq ft unit into two 1k sq ft units, one of which will be ours. The electrical supply comes into the unit that will not be ours, so the landlord is putting a new supply into our bit for us as part of the deal. The currently installed supply is three phase, with each phase company-fused at 100A, as far as I can see. We have approached NPower for a meter, and one of the questions on the application form refers to the type of meter required. The two three phase options given are "Three Phase Whole Current" and "Three Phase CT".I have not the slightest idea what the difference between these is, or which it will be that we need ?? I have checked with the landlord to make sure that it is a three phase supply that he is bringing over to our unit, and he says that we will "need a three phase meter for a 40kVA supply" First question then. If each phase is currently fused at 100A, does that mean that the incoming supply is 25kVA per phase i.e. 75kVA, and that by dividing it between the two newly created premises, that is how he arrives at 40kVA ?Our demand will be fairly high. There will be two electrical fryers, each loading at 2 x 9kW, so I guess if they are all on and heating up together, that would be a demand of 36kW. There is also a ceiling mounted airco / heater unit that I don't know the specs for . It's not very big - maybe 2 ft square. Other than that, the demand will be moderately low - some fume extraction which is only a few amps, a couple of small fridges and freezers, lights (not more than 1kW) and small odds and sods for a normal ring main. So, given the *potential* for everything being on together, does that mean that the supply he is proposing giving us, is going to be adequate for our needs ?Another question on the form is "Voltage - please delete" The three options given are 415V 11kV and 33kV. I assume that the correct answer there is 415V as it's...