2006-08-24 10:20:04 · 9 answers · asked by Anonymous in Consumer Electronics ➔ Other - Electronics
Almost the same.
Only if the 120W load drew its current exactly in phase with the alternating volts cycle would the rating be 120VA.
A 120 watt appliance might draw more than 120VA, (because, through parts of the cycle the device is returning energy to the transformer (minus Watts) but still passing current, the net power usage is only 120 watts)
On the other hand, if a 120VA the load drew current out of phase with the voltage you would still need to multiply the volts by the amps to arrive at the VA, though it would produce less than 120 watts net power output.
As best I understand.
Hopefully a more definitive answer will be supplied.
2006-08-24 10:34:12 · answer #1 · answered by x 3 · 0⤊ 0⤋
Question - What is the difference between a volt-amp (VA) and a Watt?
Equipment I have seen (such as computer backup power supplies)
have 2 different numbers for this rating. The watt rating is
typically 65% of the VA rating.
In the strictest sense, a volt-amp and a Watt are the same. Based on the
fact that your device has a Watt equal to 65% of a volt-amp, I expect they
are not used to mean the same thing in AC electronics. It would seem that
the volt-amp refers to the maximum power flow, while the Watt refers to a
time-averaged power flow. In AC circuits, Power flow varies as a sine
function. The "root-mean-square" rate of flow is approximately 65% of the
maximum flow.
2006-08-24 10:28:10 · answer #2 · answered by Mick H 3 · 0⤊ 1⤋
Basically Yes. 120/240=0.5Amps. If it was 120 volt it would be 120/120 =1 amp. If the output was 120va @ 12 volts it would be 120/12=10 amps.
2006-08-24 11:27:02 · answer #3 · answered by jayktee96 7 · 0⤊ 1⤋
No, Because
Power = V* A * Power factor
Power factor depends on the type of equipment. Hence depending on a load, for example if it is a PC power supply your PF can be safely assumes as 0.8, if it an incandescent bulb you can assume PF to be 1. For a consumer electronics item you can assume it to 0.7-0.8.
2006-08-24 10:39:42 · answer #4 · answered by Indori 2 · 0⤊ 0⤋
My hubby says: "I dare say yes, because a watt is a unit of power and power is computed by voltage times current. P=VI."
Hope that helps.
2006-08-24 10:29:14 · answer #5 · answered by KoKo 3 · 0⤊ 1⤋
no i= e over r =about 20 watts
2006-08-24 22:29:24 · answer #6 · answered by Anonymous · 0⤊ 0⤋
divide the VA figure by 1.4 to get the true continuous wattage figure, rough-and-ready, but fairly accurate.
2006-08-24 15:52:06 · answer #7 · answered by Phish 5 · 0⤊ 1⤋
You have a transformer!?! Is it Optimus Prime! I love him...
2006-08-24 10:25:07 · answer #8 · answered by young108west 5 · 0⤊ 0⤋
it's possible
2006-08-27 19:32:11 · answer #9 · answered by Anonymous · 0⤊ 0⤋