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Yes. they should. The windings in a three phase motor are identical, and provided they are fed with a supply that has the phases at the correct voltage, and at the correct 'phase angles' to each-other, they should each draw the same current from each supply line.

(Motor windings are a 'balanced' load - they will all draw the same current from the lines if the supply is okay and the windings are connected correctly, and have no shorts or opens in them.)

Some three phase motors can be connected to run off of a single phase line, using capacitors to give phase shifts to simulate 3 phase. This is an 'unbalanced' 3 phase supply as far as the motor is concerned, and while it WILL work, the motor will develop less staring torque, less full load power, and more noise - and it WILL draw different currents in each 'phase' while running.

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Q: Should all 3 phases of a motor draw the same amperage?
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