Working out Amps?

[Mike2007]

15KW
230VAC
What would the amps be?

Do I still need the resistance of cable to calculate?

 

[Spark123]

No, just work out watts/volts and it gives you amps.
15000/230=65.22A

 

[westie101]

15KW = 15,000 W (power =P)

P/V = A

So 15,000/230 =

I'll let you do the sum!

 

[EFLImpudence]

15000W/230V =

 

[Mike2007]

I did that one first (just seemed too easy)
Cheers!

 

[ericmark]

Watts = Volts x Amps x Power factor correction so to transpose.
Amps = Watts/Volts/Power factor correction so if power factor is unity then it will be 65.2173913 Amps but it could be higher if power factor is not unity.

 

[Mike2007]

Could you get resistance using these figures then?

 

[EFLImpudence]

 

[Stoday]

15000W/230V =

In theory.

But we live in the real world, where (in the UK) the voltage at a socket could be anything between 205V and 253V.

If the appliance is a pure resistance, such as a heater, the current would be between 58.1A and 71.7A [A = P/V * E/V, where V = nameplate voltage and E = actual voltage]

It’s more complicated if the load has an inductive or capacitive component (e.g. a fluorescent light) or if the resistance of the load varies with current (e.g. an incandescent lamp).

 

[EFLImpudence]

In theory.
But we live in the real world, where (in the UK) the voltage at a socket could be anything between 205V and 253V.
If the appliance is a pure resistance, such as a heater, the current would be between 58.1A and 71.7A [A = P/V * E/V, where V = nameplate voltage and E = actual voltage]
It’s more complicated if the load has an inductive or capacitive component (e.g. a fluorescent light) or if the resistance of the load varies with current (e.g. an incandescent lamp).

Yes, I know that's true.
I did think of mentioning it to the OP but he was just asking about two figures with no mention of any appliances.

Perhaps the regulations should amend the nominal voltage to 250V +1%/-15.6% to be on the safe side.

15KW
230VAC
What would the amps be?

15000W/230V =

That is how it's done.

 

[westie101]

Perhaps the regulations should amend the nominal voltage to 250V +1%/-15.6% to be on the safe side.

Or even 240V +/- 6%

 

[securespark]

Grrrr.....Pesky DNO's with their own rules!

 

[Paul_C]

Or even 240V +/- 6%

Gets my vote!

 

[Stoday]

Better still, choose a nominal voltage that's nearer to the typical supply voltage.

E.g. 245V +3%, -12%.

 

[bernardgreen]

Even better . when designing the safety critical things like fuse ratings and maximum safe current use the highest voltage in the calculation of currents that will flow.