Which products are affected?
9300EP position controller <= V6.2
What happens?
If, in case of an inverted position polarity (C1206 = 1), QSP is deactivated while the QSP ramp is executed or if the controller is enabled after controller inhibit (CINH) the position profile generator does not accept the current speed MCTRL-NACT with the correct sign. The profile generator starts with the inverted speed at first. As a result, a corresponding sudden change in the speed setpoint occurs which, in turn, results in a sudden change in torque.
When does the problem occur?
The problem occurs in case of an inverted position polarity (C1206 = 1) and if the QSP function is deactivated while the QSP ramp is executed or if the controller inhibit (CINH) is enabled while the drive is still rotating in an uncontrolled way (coasting).
Possible diagnostics?
Analyse the behaviour when QSP is deactivated while the QSP ramp is executed or when the controller is enabled while the drive is still rotating.
Short-term measures/recommendations?
After activation of the QSP function decelerate the drive along the ramp until standstill. Do not deactivate QSP before standstill. Do not enable the controller before the motor has nearly been stopped.
Evaluation:
The problem can easily be eliminated by applying the short-term measures described before.
