Kw to kva conversion

[eds54]

Hi All I need to apply for a new 100a x 3ph&n supply but I need to know the kva equivalent and figured the quickest way to find out is to ask you guys. Thanks in advance.

 

[telectrix]

you need to know the power factor of any equipment that is to be installed. . rule of thumb is 0.8. the divide the kW by the pf to get KVA.

 

[Spoon]

Google has lots of results for this.

 

[Sharpend]

Hi All I need to apply for a new 100a x 3ph&n supply but I need to know the kva equivalent and figured the quickest way to find out is to ask you guys. Thanks in advance.

The art of laziness in a single post.

Probably took longer to write the post than it would to google.

 

[cobrauk]

UK POWER state 25kva for 100amp 3phase and 23kva for 100amp single phase

http://www.rapidtables.com/calc/electric/Amp_to_kVA_Calculator.htm

 

[1ManRiot]

you need to know the power factor of any equipment that is to be installed. . rule of thumb is 0.8. the divide the kW by the pf to get KVA.

This ^

kW = I x V x √3 (x power factor x efficiency) (transpose accordingly)

Power factor = cosΘ = R / Z = kW / kVA (again transpose accordingly, so kW / PF)

Or trig if you like drawing triangles!

As someone above has stated, a lot of our 3 phase stuff uses a 25kVA supply.

 

[tissparks]

If you have android or iPhone there's plenty of apps that can do it for you, but you can't beat the good old fashioned knowledge, pencil and paper

 

[Tanker222]

230 v 100 A is definitely 23 kVA on a single-phase supply. A three phase supply with a line-to-neutral voltage of 230 v the kVA delivered is three times as much, 69 kVA. That would normally be described as 400 v 3-phase, which is 400v line-to-line, in other words the normal LV supply going down a street.

 

[eds54]

Cheers Tanker222. A simple answer to a simple question and now I know.

 

[DPG]

230 v 100 A is definitely 23 kVA on a single-phase supply. A three phase supply with a line-to-neutral voltage of 230 v the kVA delivered is three times as much, 69 kVA. That would normally be described as 400 v 3-phase, which is 400v line-to-line, in other words the normal LV supply going down a street.

Not really a conversion from kva to kw though - you would need to involve power-factor for that. 230V x 100A = 23000 watts is just straight Ohm's law. Daz

 

[mechelec]

Cheers Tanker222. A simple answer to a simple question and now I know.

And you are happy to take the word of someone on a forum who you don't know from Adam ! He could be telling you anything.


As it happens based on 230v phase voltage and a power factor of 1 he isn't wrong.

 

[Tanker222]

230 v 100 A is always 23 kVA, doesn't matter about the PF.

 

[mechelec]

230 v 100 A is always 23 kVA, doesn't matter about the PF.

I think you will find 230v phase voltage and 100A phase current will give 23KW not 23KVA. If the load is inductive or capacitive then the power factor must be taken into account and will give KVA

 

[tissparks]

As mechelec says I'm afraid. Kw is purely resistive or pf of 1. That's why generators are rated for KVA because you don't know the load.

 

[Geoffsd]

You're both right but answering different questions.
The OP asked what kVA would 100A be.

S[SUB](kVA)[/SUB] = I[SUB](A)[/SUB] × V[SUB](V)[/SUB] / 1000

P[SUB](kW)[/SUB] = I[SUB](A)[/SUB] × V[SUB](V)[/SUB] / 1000