GE Fuji Electric AF-300 Mini Startup Manual page 90

Possible Causes
(6) The value set for the
torque boost (F09) was
too high.
(7) The V/f pattern did not
match the motor.
[9] dbH Overheat protection for braking resistor
Problem Thermal protection for braking resistor activated.
Possible Causes
(1) Braking load was too
heavy.
(2) The deceleration time
was too short.
(3) Incorrect data values set
for function codes F50
and F51.
NOTE: The drive estimates braking resistor overheating by monitoring load, not by measuring actual temperature. If
the resistor is used more frequently than the data values for function codes F50 and F51 indicate, the alarm may be
triggered even if the braking resistor does not appear to be hot. If the resistor is used to the limit of its capacity, the
data values for function codes F50 and F51 must be changed and the surface temperature of the resistor checked.
[10] OL1 Electronic thermal overload relay
Problem Electronic thermal function for motor overload detection activated.
Possible Causes
(1) Excessive load.
(2) The acceleration/
deceleration time was
too short.
What to Check and Suggested Measures
CHECK
Check the data of function code F09 and readjust the data so that the motor does not stall even if you set
a lower value.
SUGGESTED ACTIONS
– Change the data for this function code.
CHECK
Check if the base frequency (F04) and rated voltage at base frequency (F05) match the values on the
motor nameplate.
SUGGESTED ACTIONS
– Match the function code data to the motor nameplate values.
What to Check and Suggested Measures
CHECK
Recalculate the relation between the braking load and braking capacity.
SUGGESTED ACTIONS
– Reduce the braking load.
– Revise the braking resistor in order to improve braking ability. Resetting the data of function codes F50
and F51 is also required.
CHECK
Recalculate the required deceleration torque and time from the moment of inertia for the load and the
deceleration time.
SUGGESTED ACTIONS
– Increase the deceleration time (F08, E11, and H54).
– Use a bigger braking resistor in order to improve braking ability. Resetting the data for function codes
F50 and F51 is also required.
CHECK
Check the braking resistor specifications.
SUGGESTED ACTIONS
– Change the data for function codes F50 and F51 as necessary.
What to Check and Suggested Measures
CHECK
Measure the output current.
SUGGESTED ACTIONS
– Reduce the load (e.g. lighten the load before overload occurs using the overload early warning (E34)).
CHECK
Check that the motor generates enough torque for acceleration/deceleration. This torque is calculated
using the moment of inertia for the load and the acceleration/deceleration time.
SUGGESTED ACTIONS
– Lengthen the acceleration/ deceleration time (F07, F08, E10, E11 and H54).
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