If The Direction Of The Motor Rotation Is Reversed; If The Motor Stalls Or Acceleration Is Slow - Omron VARISPEED F7 User Manual

The motor only rotates in one direction.
"Reverse run disabled" may be selected. If b1-04 (Prohibition of Reverse Operation) is set to 1 (reverse run
prohibited), the Inverter will not accept any reverse run commands.

If the Direction of the Motor Rotation is Reversed

If the motor rotates in the wrong direction, the motor output wiring may be incorrect. When the Inverter oper-
ates in the forward direction, the forward direction of the motor will depend on the manufacturer and the
motor type, so be sure to check the motor specification
The direction of the motor rotation can be reversed by switching two wires among U, V, and W. If using an
encoder, the polarity will also have to be switched. If the Inverter is operated in V/f mode also parameter
b1-04 can be used to change the rotation direction.

If the Motor Stalls or Acceleration is Slow

The torque limit has been reached.
When a torque limit has been set in parameters L7-01 to L7-04, the output torque will be limited according
these settings. Therefore the motor may not develop enough torque to accelerate or the acceleration time might
be very long.
If torque limits have been set for the multi-function analog input (H3-09 = 10 to 12 or 15), check the signals.
The stall prevention level during acceleration is too low.
If the value set for L3-02 (Stall Prevention Level during Acceleration) is too low, the acceleration time will be
increased. Check that the set value is suitable and that the load is not too large for the motor.
The stall prevention level during run is too low.
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If the value set for L3-06 (Stall prevention level during run) is too low, the motor speed and torque will be lim-
ited. Check that the set value is suitable and that the load is not too large for the motor.
Auto-tuning has not been performed for vector control
Vector control will not work properly if auto-tuning has not been performed. Perform auto-tuning, or set the
motor parameters through calculations.
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