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Inductance Range of the P7000 Stepper drive

The P7000 was designed primarily for high inductance motors.  The AC model has two ranges of inductance based on bus voltage, and the DC model has its own inductance range.

AC power (P70360):

160VDC bus - optimal motor inductance range is 7 - 30 mH

​320VDC bus - optimal motor inductance range is 50 - 200 mH

DC power (P70530):

optimal motor inductance range is 2 - 15 mH


If the motor inductance is lower than the drive's allowable range, then the drive is at risk of overheating and damaging the power stage.

If the motor inductance is higher than the drive's allowable range, then there is no risk of damage.  But there will be degraded performance.  Higher inductance and/or lower voltage means the drive takes more time to push current through the windings, thus lowering the motor's response.

The P70360 drive has a voltage doubler.  Unless the voltage doubler is bypassed, the drive bus voltage will be about 320VDC.  The P7000 manual shows wiring diagrams for achieving the desired bus voltage.