Fuji Electric FRENIC-HVAC User Manual page 645

[ 13 ] OL1 Overload of motor 1
Problem Electronic thermal protection for motor activated.
Possible Causes
(1) The electronic thermal
characteristics do not match the
motor overload characteristics.
(2) Activation level for the
electronic thermal protection
was inadequate.
(3) The specified acceleration/
deceleration time was too short.
(4) Overload.
(5) Excessive torque boost specified
(F09)
[ 14 ] OLU Inverter overload
Problem Temperature inside inverter has risen abnormally.
Possible Causes
(1) Temperature around the inverter
exceeded the inverter's
specification range.
(2) Excessive torque boost specified
(F09)
(3) The specified acceleration/
deceleration time was too short.
(4) Overload.
(5) Ventilation paths are blocked.
9.3 If an Alarm Code Appears on the Monitor
What to Check and Suggested Measures
Check the motor characteristics.
 Reconsider the data of function codes (P99, F10 and F12).
 Use an external thermal relay.
Check the continuous allowable current of the motor.
 Reconsider and change the data of function code F11.
Recalculate the acceleration/deceleration torque and time needed for
the load, based on the moment of inertia for the load and the
acceleration/deceleration time.
 Increase the acceleration/ deceleration time (F07, F08, E10
through E15, and H56).
Measure the output current.
 Reduce the load (e.g. Use the overload early warning (E34) and
reduce the load before the overload protection is activated.). (In
winter, the load tends to increase.)
Check whether decreasing the torque boost (F09) does not stall the
motor.
 If no stall occurs, decrease the F09 data.
What to Check and Suggested Measures
Measure the temperature around the inverter.
 Lower the temperature (e.g., ventilate the panel where the inverter
is mounted).
Check whether decreasing the torque boost (F09) does not stall the
motor.
 If no stall occurs, decrease the F09 data.
Recalculate the acceleration/deceleration torque and time needed for
the load, based on the moment of inertia for the load and the
acceleration/deceleration time.
 Increase the acceleration/deceleration time (F07, F08, E10
through E15, and H56).
Measure the output current.
 Reduce the load (e.g., Use the overload early warning (E34) and
reduce the load before the overload protection is activated.). (In
winter, the load tends to increase.).
 Decrease the motor sound (Carrier frequency) (F26).
If the carrier frequency is high, output must be reduced. For
details, refer to "2.6 Derating of Rated Output Current."
 Enable overload prevention control (H70).
Check if there is sufficient clearance around the inverter.
 Change the mounting place to ensure the clearance.
Check if the heat sink is not clogged.
 Clean the heat sink.
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