Bill said:
Hello,
If the line to line voltage is 208V, then three legs @ 120V will give
666.17 Amps. We should note that this is a total current for the
generator. Namely, each leg can supply a current of approx. 222.05
Amps. So both of you are correct; it depends on what you consider to be
your reference.
Although I agree that each phase can carry 222.05 amps, there is no way to
combine the three phases to supply a 666.17 Amp load. The vector sum of the
three 222.05Amp phases would be zero (ideally).
When rating three-phase equipment, I've always seen the line current used,
not 3X that value. Line-line voltage and balanced line current is the
normal way to describe their ratings.
Most 3-phase generators are also limited on the amount of imbalance they can
tolerate. This unit probably cannot be used to power a single phase load at
222 Amps on only one phase with the others unloaded. Such an unbalance
would likely burn the rotor. I've seen imbalance limits of 5 to 15%
depending on the size of the unit, but others may tolerate more (or less).
daestrom