What is kVA of domestic 1phase and 3 phase supply

tired_dad

Getting a quote for upgrading .

Form requires this info and I’m not sure what the numbers are

Ta

tacpot12

The KVA is a measure of the power provided by the supply. For your existing single phase supply it is 230v multiplied by the size of the supply fuse, unless you know what this is, I would use 100A.

If you are upgrading to a three phase supply, the KVA required is calculated 1.73 multiplied by 400v multiplied by the number of amps you need. If you don't know the number of amps you need yet, ask your electrician.

I would not submit the form without having your electrician sign them off as being correct, otherwise you run the risk of a very expensive mistake.

Risteard

The form isn't interested in the rating of the supply that you have. What they want to know is the capacity required (taking diversity into account).

Someone competent will fill this in for you having been remunerated for their expert advice.

ComicGeek

Risteard wrote: »

The form isn't interested in the rating of the supply that you have. What they want to know is the capacity required (taking diversity into account).

Someone competent will fill this in for you having been remunerated for their expert advice.

Indeed - I had a client who asked for 120 kVA for each of 10 houses, giving a grand total of 1200 kVA for a fairly small site. They still tried to argue it was right with UKPN, and couldn't understand why they wouldn't provide a quote for the connections...

Robin9

A domestic supply may well have installed equipment - cooker, shower, water heater, lights, totalling 30 kva. But you don't use all of this at the same time and your demand may well only be 5kva.

In the industrial market getting this right is very important because you may be on a tariff which has a capacity component - asking for 100kva and using only 30kva is an expensive mistake.

Risteard

ComicGeek wrote: »

Indeed - I had a client who asked for 120 kVA for each of 10 houses, giving a grand total of 1200 kVA for a fairly small site.

LOL! Across the border the standard domestic single phase supply is 12kVA with a 16kVA "enhanced" supply available for more money. The standard supply is almost always what is taken.