KEB COMBIVERT F5 Reference Manual page 182

LC - Control Setting Parameters
When using induction motors, the drive may be run open loop on
i
inspection to verify whether the encoder functions normally. By setting
the parameter LC01 Motor Control = Open Loop V/Hz, the inverter runs
the motor open loop. The encoder feedback (motor speed) is displayed
in Diagnostics Screen #2 or parameter DG07 Motor Speed, but has no
effect on the operation of the motor. Therefore, this mode can be used
to verify whether the encoder is functioning properly. Generally, when
running empty car up the actual motor speed should be equal to the set
speed. If these values are off by more than 20 rpm when running empty
car up, there is most likely an encoder or encoder cable problem.
Running an induction motor in open loop can also be used to rule out
any issues when troubleshooting due to encoder feedback, motor data
settings, and speed control settings. The only parameter available for
adjustment in open loop V/Hz mode is LC32 Low Speed Torque Boost.
When using permanent magnet synchronous motors only closed loop
operation is permitted.
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Running V/Hz mode at high speed or leveling speed can result in high
motor currents and or poor performance. Always verify that this parameter
is set correctly before running in automatic mode!
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