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Old 10-26-2014, 12:23 PM   #1271 (permalink)
cts_casemod
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Great news, Paul

When you say hard acceleration/deceleration, what exactly do you mean?

On mine, I limited the maximum allowable rate of change. The motor should take no less than 3 seconds from zero to 3500RPM (120Hz). This is actually much faster than what I have seen on operation. The reason being, if there is a fault, the actual encoder value will drift faster than the speed ramp allows and therefore I can measure this parameter as a fault output to switch the inverter off.

This is generally a better indicator for an encoder fault than waiting for the pulse rate to go to zero, specially if the fault is intermittent.

When you say field weakening, do you mean after it runs out of voltage or during low torque demand?

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