Mitsubishi Electric FR-D720S SC EC Instruction Manual page 444

Causes and corrective actions
Operation Panel
Indication
Name
Description
Check point
Corrective action
Operation Panel
Indication
Name
Description
Check point
Corrective action
Alarm
When an alarm occurs, the output is not shut off. You can also output an alarm signal by making
parameter setting. (Set "98" in any of Pr. 190, Pr. 192 or Pr. 197 "Output terminal function se-
lection". Refer to section 6.9.5).
Operation Panel
Indication
Name
Description
Check point
Corrective action
7 - 8
UV
Undervoltage
If the power supply voltage of the inverter decreases, the control circuit will not perform nor-
mal functions. In addition, the motor torque will be insufficient and/or heat generation will
increase. To prevent this, if the power supply voltage decreases below about 230VAC, this
function stops the inverter output and displays. An alarm is reset when the voltage returns
to normal.
Check that the power supply voltage is normal.
Check that the power supply voltage is normal.
SA
Safety stop
Appears when safety stop function is activated (during output shutoff).
Check if the shorting wire between S1 and SC or between S2 and SC is disconnected
when not using the safety stop function.
When not using the safety stop function, short across terminals S1 and SC and across
S2 and SC with shorting wire for the inverter to run.
If SA is indicated when across S1 and SC and across S2 and SC are both shorted while
using the safety stop function (drive enabled), internal failure might be the cause.
Check the wiring of terminals S1, S2 and SC and contact your sales representative if the
wiring has no fault.
FN
Fan fault
For the inverter that contains a cooling fan, "FN" appears on the operation panel when the
cooling fan stops due to an alarm or different operation from the setting of Pr. 244 "Cooling
fan operation selection".
Check the cooling fan for an alarm.
Replace the cooling fan.
FR-PU04
—
FR-PU07
FR-PU04
—
FR-PU07
FR-PU04
FN
FR-PU07
Troubleshooting