Motor Rotates In Opposite Direction; Speed Greatly Differs From The Setting; Motor Current Is Large; Speed Does Not Increase - Mitsubishi Electric FR-S500 Instruction Manual

7.5.2 Motor rotates in opposite direction

Check that the phase sequence of output terminals U, V and W is correct.
Check that the start signals (forward rotation, reverse rotation) are connected
properly.
Check the setting of Pr. 17 "RUN key rotation direction selection".

7.5.3 Speed greatly differs from the setting

Check that the frequency setting signal is correct. (Measure the input signal
level.)
Check that the following parameter settings are correct (Pr. 1, Pr. 2, Pr. 19,
Pr. 38, Pr. 39, Pr. 95, C2 to C7).
Check that the input signal lines are not affected by external noise. (Use
shielded cables)
Check that the load is not too heavy.
7.5.4 Acceleration/deceleration is not smooth
Check that the acceleration and deceleration time settings are not too short.
Check that the load is not too heavy.
Check that the torque boost setting is not too large to activate the stall
prevention function.

7.5.5 Motor current is large

Check that the load is not too heavy.
Check that the torque boost setting is not too large.

7.5.6 Speed does not increase

Check that the maximum frequency setting is correct.
Check that the load is not too heavy. (In agitators, etc., load may become
heavier in winter.)
Check that the torque boost setting is not too large to activate the stall prevention function.
Check that the brake resistor is not connected to terminals P-P1 accidentally.

7.5.7 Speed varies during operation

When slip compensation is selected, the output frequency varies with load
fluctuation between 0 and 2Hz. This is a normal operation and is not a fault.
1) Inspection of load
Check that the load is not varying.
2) Inspection of input signal
Check that the frequency setting signal is not varying.
Check that the frequency setting signal is not affected by noise.
Check for a malfunction due to an undesirable current when the
transistor output unit is connected.
3) Others
Check that the wiring length is not too long.
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Troubleshooting
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