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Default 208 3PH question


"Robert Swinney" wrote in message
...
Yes, but !! Be careful in caculating VA from current measured with a
clamp-on type of ammeter,
though. In as much as E and I are out of phase, any leg current measured
with clamp-ons will not be
accurate. Full load current will be equal to 3 x that of current in each
leg. The formula is:

3-phase KVA = (Volts x Amps x Sq. root of 3) / (1000)


In the formula above, Amps would be the circuit current. Full load current
(as in FLA) is the same as the current on one leg, if we're talking about
the same thing. The only way you can triple the amps in this case is if you
multiply by 120, which makes sense with 208 wye since it could be supplying
three 120 V circuits with a neutral. That math, however, doesn't work with
other three phase voltages.

Bob Swinney
"dan" wrote in message
...
When figuring watts or VA on a three phase circuit, do you triple the
amps measured on one leg?

Thanks.
--

Dan H.