Errors (Alarms); Error (Alarm) Definitions - Mitsubishi Electric FR-A500 Instruction Manual

5.1 Errors (Alarms)

If any fault has occurred in the inverter, the corresponding protective function is activated and the error
(alarm) indication appears automatically on the PU display. When the protective function is activated, refer to
"5.2 Troubleshooting" and clear up the cause by taking proper action. If an alarm stop has occurred, the
inverter must be reset to restart it.
• When the protective function is activated, take the appropriate corrective action, then reset the inverter,
and resume operation.
• Resetting method
When the protective function is activated and the inverter has stopped its output, the inverter output is kept
stopped (and the motor is coasted to a stop). Unless reset, therefore, the inverter cannot restart. To reset,
use any of the following methods: switch power off once, then on again; short reset terminal RES-SD for
more than 0.1s, then open; or press the
help function of the parameter unit). If RES-SD are kept shorted, the operation panel shows "Err." and the
parameter unit indicates that the inverter is being reset.
5.1.1

Error (alarm) definitions

(1) Major faults
When the protective function is activated, the inverter output is shut off and the alarm is output.
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
STOP
RESET
E.OC1
Overcurrent shut-off during acceleration
When the inverter output current reaches or exceeds approximately 200% of the
rated current during acceleration, the protective circuit is activated to stop the
inverter output.
This indication also appears when the start signal is entered with power supplied to
only the R1<L > and S1<L
11
Check for sudden acceleration.
Check for long descending acceleration time of lift applications.
Check for output short circuit.
Check that main circuit power (R, S, T 〈 L
• Increase the acceleration time. (Decrease the descending acceleration time.)
• If "E.OC1" is always lit at a start, disconnect the motor once and then start the
inverter. If "E.OC1" is still lit, contact your sales representative.
• Supply main circuit power (R, S, T 〈 L
E.OC2
Overcurrent shut-off during constant speed
When the inverter output current reaches or exceeds approximately 200% of the
rated current during constant speed, the protective circuit is activated to stop the
inverter output.
Check for sudden load change.
Check for output short circuit.
Keep load stable.
PROTECTIVE FUNCTIONS
key of the operation panel or parameter unit (use the
FR-PU04
> terminals.
21
〉 ) is supplied.
, L , L
1 2 3
〉 ).
, L , L
1 2 3
FR-PU04
192
OC During Accs
Stedy Spd OC