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3 Phase Motor Amp Draw

3 Phase Motor Amp Draw

3 Phase Motor Amp Draw

(OP)
If I have a piece of equipment (electric oven used for burn-in) that states on it's power label the following:

Power: 480V 60Hz 3phase
Line Current: (amps per phase) 33.0

Does that mean it needs 99.0 amps (33.0 x 3 phases)  or 11.0 amps (33.0 / 3)?

I think it is 99.0 amps.

RE: 3 Phase Motor Amp Draw

It means that it needs 33 amps on each phase.

Add the three currents together and you magically get zero amps.

RE: 3 Phase Motor Amp Draw

(OP)
Cool - that's what I told my coworker.  Another coworker was thinking it was 33A total.

Thanks!

RE: 3 Phase Motor Amp Draw

I am not EE, but I asked one co-worker EE and he says the amp drwa is 33 amps.

RE: 3 Phase Motor Amp Draw

It is 33 amps Total. Phase 1 current draw 33 amps, phase 2 current draw 33 amps, phase 3 current draw 33 amps = a Total of 33 amps MAX! Not 99 amps Total. Three phase 40 amp breaker or fuse for power distribution.

RE: 3 Phase Motor Amp Draw

(OP)
Thanks!  I will let my coworker know - that is what my plant manager said as well when he replied last night.

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