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TROUBLE SHOOTING
7-15
10.
“OL1” Electronic thermal overload relay
Problem Electronic thermal function for motor overload detection activated.
Possible Causes
What to Check and Suggested Measures
1.
Load was too heavy.
Measure the output current.
→
Lighten the load (e.g. lighten the load before overload occurs
using the overload early warning (E34).
2.
The acceleration /
deceleration time was
too short.
Check that the motor generates enough torque for
acceleration/deceleration, This torque is calculated from the moment
of inertia for the load and the acceleration/deceleration time.
→
Increase the acceleration/deceleration time (F07, F08, E10, E11
and H54).
3.
The characteristics of
electronic thermal did
not match those of the
motor overload.
Check the motor characteristics.
→
Reconsider the data of function codes P99, F10 and F12.
→
Use an external thermal relay.
4.
Activation level for
the electronic thermal
relay was inadequate.
Check the continuous allowable current of the motor.
→
Reconsider and change the data of function code F11.
11.
“OLU” Overload protection
Problem Temperature inside inverter rose abnormally.
Possible Causes
What to Check and Suggested Measures
1.
Temperature around
the inverter exceeded
that of inverter
specifications.
Measure the temperature around the inverter.
→
Lower the temperature (e.g. ventilate the enclosure well).
→
Lighten the load.
2.
The service life of the
cooling fan has
expired or the cooling
fan malfunctioned.
Check the accumulated running time of cooling fan (E52=2).
→
Refer to “Reading Maintenance Information”.
→
Replace the cooling fan.
Visually check that the cooling fan rotates normally.
→
Replace the cooling fan.
3.
Air vent is blocked.
Check if there is sufficient clearance around the inverter.
→
Increase the clearance.
Check if the heat sink is clogged.
→
Clean the heat sink.
4.
Load was too heavy.
Measure the output current.
→
Lighten the load (e.g. lighten the load before overload occurs
using the overload early warning (E34).
→
Decrease the carrier frequency (F26).
→
Enable overload protection control (H70).
Summary of Contents for MWHE20
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Page 12: ...SPECIFICATION COMPONENT IDENTIFICATION 2 3 C B ...