N

nickblake

My brains switched off chaps and i can remember how to calculate 3 phase kva

i know its V x I x 1.73 / 1000

so is it 230 or 400 x I x 1.73 / 1000

fee a right numpty cant belive ive forgotten it not done 3 phase calcs for a while please enlighten me to the correct figures then ill give my self a good slapping:D
 
Example 1

A 415 volt, three phase generator provides 200 Amp. Calculate the kW and kVA of this generator.
kW = V x I P.F. x ÷ 1000 = 415 x 200 x 0.8 x 1.732 ÷ 1000 = 115 kW
kVA = kW ÷ P.F. = 115 ÷ 0.8 = 143 kVA
Example 2

To calculate the current (Amps) available from a 150 kVA generator at 415 Volts
kW = V x I x √3 ÷ 1000 Therefore I = kVA x 1000 ÷ V x √3 = 208 Amps
Example 3

To calculate the size of a generator required to provide 150 Amps @ 440 Volt
kW = V x I x  ÷ 1000 = 440 x 150 x 1.732 ÷ 1000 = 114 kW
 
VA = √3 x Vl xIl

since VA = watts/PF




edit and it will be 400V
 
Last edited by a moderator:
Thanks guys the pennys dropped im in the process of giving myself a slap ,im a right bleary eyed parrot faced wassok duuuuuu
 

OFFICIAL SPONSORS

Electrical Goods - Electrical Tools - Brand Names Electrician Courses Green Electrical Goods PCB Way Green 2 Go Pushfit Wire Connectors Electric Underfloor Heating Electrician Courses Heating 2 Go
These Official Forum Sponsors May Provide Discounts to Regular Forum Members - If you would like to sponsor us then CLICK HERE and post a thread with who you are, and we'll send you some stats etc

Advert

Daily, weekly or monthly email

Thread Information

Title
Calculating 3 phase kva
Prefix
N/A
Forum
Talk Electrician Forum
Start date
Last reply date
Replies
4

Advert

Thread statistics

Created
nickblake,
Last reply from
nickblake,
Replies
4
Views
15,636

Advert

Back
Top