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Unregistered
09-27-2007, 07:23 PM
How Do You Determine Kilowatts From Amps? I Have 288 Amps How Do You Determine How Many Kilowatts That Is?

thesmartfisherman.com
09-28-2007, 11:00 AM
What Voltage are you assuming?

The conversion of Amps to Watts is governed by the equation

Watts = Amps x Volts

For example 1 amp * 110 volts = 110 watts

In your case I will assume 110 volts so:

288 * 110v = 31,680 volts

or

31.68 Kilowatts

Unregistered
10-02-2007, 01:17 AM
288A * 110V = 31,680 Watt

but 288A on a 110V grid is unlikely; I would expect it is 480V in a three phase grid; that makes it even more difficult :-)

thesmartfisherman.com
10-02-2007, 10:57 AM
288A * 110V = 31,680 Watt

but 288A on a 110V grid is unlikely; I would expect it is 480V in a three phase grid; that makes it even more difficult :-)

That was just an example of the arithmetic.;)

Unregistered
11-21-2007, 05:55 AM
How Do You Determine Kilowatts From Amps? I Have 400 Amps How Do You Determine How Many Kilowatts That Is? at 3phase 208volts

I Have 400 Amps How Do You Determine How Many Kilowatts That Is? at 3phase 208volts

Unregistered111
11-20-2008, 04:16 PM
400amps @ 3p208

400*(3*208)=249,600w

249,600/1000=249.6

mohamed
04-10-2009, 03:55 AM
i hav motor for machine 380 v /3 phas /30 kw i whant know how many amps this motor ned

JohnS
04-10-2009, 05:14 AM
i hav motor for machine 380 v /3 phas /30 kw i whant know how many amps this motor ned

The question is whether the 380 V is measured line to neutral or line to line. If it is line to line, then it is only 219 V line to neutral.

I will assume it is line to neutral
30 kW/380 V = 78.9 A
That is the sum of the three phase currents, each phase is 26.3 A, assuming the load is balanced.
(It may need higher current during starting.)

Edit: It is actually more likely that it is 219 V line to neutral and 380 line to line.
30 kW/219 V = 137 A, 45.7 A in each phase (assuming balanced load)

MJWorner
04-13-2009, 06:39 AM
The question is whether the 380 V is measured line to neutral or line to line. If it is line to line, then it is only 219 V line to neutral.

I will assume it is line to neutral
30 kW/380 V = 78.9 A
That is the sum of the three phase currents, each phase is 26.3 A, assuming the load is balanced.
(It may need higher current during starting.)

Edit: It is actually more likely that it is 219 V line to neutral and 380 line to line.
30 kW/219 V = 137 A, 45.7 A in each phase (assuming balanced load)

A three phase induction motor would be running phase to phase (no neutral required). The calculation is: 30,000W/380V/1.73 (sqrt of 3) or45.58028441
Amps. That being said, overcurrent protection will have to be sized to carry momentary starting load of about 250%. This could be even higher in an application with large inertial loading. The calculation is assuming 100% efficiency as well, so you need to know if 30kW is the size of the motor or the consumption under load and divide the current figure by efficiency.

Note that the square root of the phasing is used as actual voltage (an hence current) in a three phase circuit is 120 electrical degrees apart so the actual currents peak 1/150 of a second apart in 50 Hz or 1/180 of a second at 60 Hz.

Motor name plate data should indicate FLA (full load amps) and LRA (locked rotor amps). Local code requirements or good engineering practice will dictate wire size and overcurrent protection.

Sounds like you are looking at wire in the #6 AWG range (~15 sq mm) with an increase in size of (~5 sq mm) for each 30m increase in length.

Of course that's looking at it from half a world away. :)

MJWorner
04-13-2009, 06:59 AM
400amps @ 3p208

400*(3*208)=249,600w

249,600/1000=249.6

That should be 400A x sq rt 3 (1.73) x 208V = 144,106.63 W or 144.1 kW.

You have to take the square root of the phases because they don't peak simultaneously but sequentially 1/180 of a second apart.

Unregistered
04-25-2009, 05:03 AM
That was just an example of the arithmetic.;)8 amp@220volt what is kilowatt

JohnS
04-25-2009, 10:58 AM
8 amp@220volt what is kilowatt

8 A x 220 V x 1 kW/1000 W = 1.76 kW

Unregistered
05-12-2009, 03:29 AM
Everyone in here forgot that to determine kW in 3 phase applications you must use the following formula:

V x A x 1.73 = W

So if you have a load of 30kW at 380V/3 Ph you would need to multiply volts times 1.73, then divide 30kW by the result.

380V x 1.73 = 657.4 30,000W/657.4 = 45.6A

If you do not use the three phase factor of 1.73 your calculation will be very incorrect, causing loss of equipment and/or personnel.

Unregistered
08-18-2009, 05:17 PM
Here's a question ??
What materal would make the best solar colector material or film to cover 50 acres.

Unregistered
10-25-2009, 10:03 AM
I am looking to put a capicitor on my a/c units how much will i sve per month if the follow are assumed.
3 phase 280 volt
when i do a ready on of a test unit i am saving 2 amps
my kilowatt per hour rate is .0983 from my utitlity bill the ac units run aproxiamatley 20 hours per day

here is my calculation did i do it right

amps(2) * 280 volts = volts 560 =kilo watts .56 * kwh cost of \$.0983 =.055 * 22 hours a day * 30 days a month = \$33.00 per month in savings

JohnS
10-25-2009, 11:41 AM
I am looking to put a capicitor on my a/c units how much will i sve per month if the follow are assumed.
3 phase 280 volt
when i do a ready on of a test unit i am saving 2 amps
my kilowatt per hour rate is .0983 from my utitlity bill the ac units run aproxiamatley 20 hours per day

here is my calculation did i do it right

amps(2) * 280 volts = volts 560 =kilo watts .56 * kwh cost of \$.0983 =.055 * 22 hours a day * 30 days a month = \$33.00 per month in savings

You will make your power company much happier, but I am not sure you will save anything at all.

Power in alternating current (ac) electricity is complicated by whether the current and voltage are in phase. The capacitor can only affect the quadrature current and affect reactive power.

If your meter measures kilowatt-hours, it should only be measuring the in-phase current times voltage and ignoring the reactive power. However, if your meter measures KVAh, it includes the reactive power. The KVA measurement ignores the phase angle or power factor and just multiples magnitude of voltage by magnitude of current.

You may need to check with your utility. However, the utility HATES reactive power (they have losses in their lines from carrying the reactive power). Their advice may not be entirely forthright if they are not able to charge reactive power.

Finally, in the details of your calculation, you need to account for this being 3-phase power. Is the 280 V measured line to line or line to neutral? Is the 2 A savings per phase or the sum of the savings in three phases. Assuming the currents are balanced, and in phase with the line to neutral voltage, the power is 3 *phase current * line to neutral voltage. If voltage is line to line, the factor of 3 is reduced to sqrt(3). If currents are unbalanced, or there is a phase angle issue, the calculation is more complex.

You may need an electrician to sort this out for you. The risk is that you might achieve real savings, or you might just make your electric company smile. Sorry I can't give a conclusive answer.

Unregistered
11-09-2009, 04:30 AM
How do i find out how many KW is 63Amps?

Unregistered
12-07-2009, 03:52 AM
[QUOTE=Unregistered;38667]How Do You Determine Kilowatts From Amps? I Have 400 amps, what does that turn out to be in watts

Unregistered
01-11-2010, 08:14 PM
[QUOTE=3 amps to kilo watt

Unregistered
02-10-2010, 02:29 PM
how convert 60 kilowatts to amps? 110 voltage.

JohnS
02-10-2010, 04:02 PM
how convert 60 kilowatts to amps? 110 voltage.

60 kW/110 V = 545.5 A

Unregistered
05-04-2010, 08:45 AM
[QUOTE=mohamed;61058]120kilowatts change to amps

JohnS
05-04-2010, 09:27 AM
[QUOTE=mohamed;61058]120kilowatts change to amps

Not enough info. Need to know the voltage, and whether it is single phase or three phase.

salah
07-05-2010, 12:03 AM
150 amps to k w

Unregistered
09-03-2010, 03:52 PM
I am trying to figure out how much electricity my pool pump is using. It is 2 Hp and a7 amps and runs 24 hours a day. I need to know how many kilowats it is using on a daily basis.

JohnS
09-03-2010, 04:12 PM
I am trying to figure out how much electricity my pool pump is using. It is 2 Hp and a7 amps and runs 24 hours a day. I need to know how many kilowats it is using on a daily basis.

I think you have a typo there. Not sure what a7 amps is.

Amps X Volts = Watts
Divide by 1000 to get kilowatts and multiply by 24 hours/day to get kilowatt hours per day.

From 2 HP rating, I'm guessing you might mean 17 A, 120 V, so thats 2.04 kW. Running 24/7, it is using 49 kWh per day.

For ac power, there is something called power factor. The power might be a little less if current and voltage are not exactly in phase. This is usually minor in single phase circuits.

Unregistered
09-06-2010, 08:51 PM
if i was putting power back into the grid at 1120 amp hr in 12volts in 24hr day. haw many kw hr have i made in 240volt. at 44cents per kw hr, have i made or saved 164.25 in that 24hr period.

JohnS
09-07-2010, 04:29 AM
if i was putting power back into the grid at 1120 amp hr in 12volts in 24hr day. haw many kw hr have i made in 240volt. at 44cents per kw hr, have i made or saved 164.25 in that 24hr period.

1120 Ah is 1.12 kAh. At 12 V, it is 13.4 kWh.
At 100% efficiency in the inverter, that is what you would put back in the grid. You'll be lucky if the efficiency is enough to put back 12 kWh, so \$5.28.

\$0.44/kWh is a wicked electrical rate. I pay the utility \$0.12/kWh.

Unregistered
01-12-2011, 07:26 AM
Dear sir we have D/H which cunsuptions 80 Amps 3phase power how to convert in to kilowatts

Roykutty
03-21-2011, 07:51 PM
38667]How Do You Determine Kilowatts From Amps? I Have 288 Amps How Do You Determine How Many Kilowatts That Is?

Unregistered
05-13-2011, 05:37 AM
Most everything that I have read here is calculating KVA, not KW. In a 3 phase system, KVA = Amps * Volts(L-L) * 1.732 (square root of 3)

The difference between KW and KVA is the power factor. In a typical motor that is fully loaded, the power factor will be somewhere in the 80% range. It decreases with load and may be somewhere around 30% in a lightly loaded motor. So:

Assuming a fully loaded 3 phase motor, KW = KVA * 0.80 (power factor). This is the amount of power that is doing useful work. The balance (KVA * 0.20) is called reactive power and is the magnetizing current required by the motor to set up the magnetic circuit inside before it can produce useful work.

Unless you have a meter that reads power factor, you are not being charged for the reactive power.

Unregistered
09-23-2011, 03:41 AM
What is the maximum Kw of load can 31/2 x 300 Sq.mm Al UG Armoured cable withstand ?

Unregistered
12-11-2011, 12:01 PM
i hav motor for machine 380 v /3 phas /30 kw i whant know how many amps this motor ned

kindly send me quote

Unregistered
12-12-2011, 03:02 AM
How Do You Determine Kilowatts From Amps? I Have 288 Amps How Do You Determine How Many Kilowatts That Is?

I have 24.4 amps, how many kilowatts does this relate to?

JohnS
12-12-2011, 03:07 AM
I have 24.4 amps, how many kilowatts does this relate to?

You also have to know the voltage. If it is alternating current, you also need to know power factor and whether it is single phase or three phase.

Unregistered
12-12-2011, 04:24 PM
400amps @ 3p208

400*(3*208)=249,600w

249,600/1000=249.6

Wrong 400*(208*1.732)=w

Unregistered
03-02-2012, 10:36 AM
I have motor for machine 420 v /3 phase /55 kw i want know how many amps this motor

Unregistered
04-01-2012, 08:11 PM
I need formula running amp to kilowatt...

hasan
04-23-2012, 01:32 PM
That was just an example of the arithmetic.;)

1amps= ? watt

Unregistered
06-28-2012, 09:06 PM
Thanks for this. Does that mean each phase will draw 45 amps or it will be distributed in 3 phases ie. 15 amps per phase.

Unregistered
07-03-2012, 02:59 PM
450 amp how many kilowatt

Robert Fogt
07-03-2012, 03:47 PM
450 amp how many kilowatt

Check out our ohm's law page here:
http://www.onlineconversion.com/ohms_law.htm

You will need to know additional information, such as the voltage.

Marc
07-25-2013, 04:25 PM
KW for 3 phase 208, 240 or 480
Add amps divided by # of legs = average amps. Multiply average amps X voltage X 1.73 = xxxx Watts. Divide by 1000 = KW

Or

Add the legs X by phase voltage for a quick rough estimate.

Single phase 120/240 or 208