Appendix 4 Troubles and Solutions
Troubles and Solutions
166
Appendix 4 Troubles and Solutions
Troubles
Check points
Motionless motor
Main circuit
• Check whether the power supply voltage between Terminals
R/L1, S/L2 and T/L3 is normal.
• Check whether the Power light is on.
• Check whether the wiring between the inverter and the motor is
correct.
Load
• Check whether the load is too heavy.
• Check whether the motor rotor is locked.
Parameters
Setting
• Check whether the starting frequency (P.13) is set too big.
• Check whether the operation mode (P.79) is correct.
• Check whether the maximum frequency (P.1) is zero.
• Check whether the reverse rotation prevention is restricted.
• Check whether the bias and gain (P.192~P.199) setting is
correct.
• Check that the frequency jump (P.91~P.96) setting is correct.
Control
circuit
• Check whether the output stop signal "MRS” is on. (Related
parameter P.80~P.84, P.86).
• Check whether the “RES” function is ON. (Related parameter
P.80~P.84, P.86).
• Check whether the external thermal relay is operating or not.
• Check whether the reset has been performed or not after the
set-off of the alarm (the ALARM light in on).
• Check whether the voltage/current signals are correctly wired.
• Check whether the functions of STF and STR are correct
(related parameter P.80~P.84, P.86).
• Check whether the wiring for the control circuit is disconnected
or has a poor contact.
Reversed motor
rotation
• Check whether the phase sequence of output terminals U/T1, V/T2 and W/T3 is
correct.
• Check whether the start signal (STF and STR) are connected correctly.
Failure to
increase the
rotation speed of
the motor
• Check whether the load is too heavy.
• Check whether the stall prevention level (P.22) is correct.
• Check whether the torque boost (P.0) is set too high.
• Check whether the maximum frequency (P.1) is effective.
Unsmoothed
acceleration /
deceleration
• Check whether the acceleration / deceleration time (P.7, P.8) is correct.
• Check whether the acceleration / deceleration curve selection (P.29) is correct.
• Check whether the voltage / current input signals are affected by noises.
Overlarge motor
current
• Check whether the load is too heavy.
• Check whether the capacity of the inverter and of the motor are well matched.
• Check whether the torque boost (P.0) is set too high.
Speed variation
during the
operation
• Check whether the voltage / current input signals are affected by noises.
• Check whether the load varies.
• Check whether the wiring length of the main circuit is too long.
