[77_Main Circuit Device Overheat]; [7E_Overload 1]; [7F_Overload 2] - Mitsubishi Electric -MR-CV User Manual

[77_Main circuit device overheat]

• The inside of the converter unit overheated.
Cause
1.
The ambient temperature exceeded the specified
value (55 °C).
2.
The power was turned on and off repeatedly
under the overload status.
3.
A cooling fan, heat sink, or opening is clogged.
4.
The converter unit has malfunctioned.

[7E_Overload 1]

• The load exceeded the overload protection characteristics of the converter unit.
Cause
1.
A current larger than the continuous output
current of the converter unit flowed.

[7F_Overload 2]

• The load exceeded the overload protection characteristics of the converter unit.
Cause
1.
A current larger than the short-time output current
of the converter unit flowed.
8 CONVERTER UNIT TROUBLESHOOTING
82
8.3 Handling methods for alarms/warnings
Check/action method
Check the ambient temperature, and if the temperature exceeds the specified value,
lower the ambient temperature.
Check if the overload status occurred frequently.
If the overload status occurred frequently, review the operation pattern.
Clean the cooling fan, heat sink, or openings.
Replace the converter unit, then check the repeatability.
Check/action method
Check the effective load ratio of the converter unit.
If the effective load ratio of the converter unit is too high, take corrective actions as
follows:
• Reduce the load.
• Check the operation pattern.
Check/action method
Check the effective load ratio of the converter unit.
If the effective load ratio of the converter unit is too high, review the operation pattern.