If An Alarm Code Appears On The Led Monitor; Oc2 Overcurrent Protection - GE Fuji Electric AF-300 Mini Startup Manual

[3] Nothing appears on the LED monitor.
Possible Causes
(1) No power supplied to the
drive.
(2) The power for the control
circuit did not reach a
high enough level.
6.3

If an alarm code appears on the LED monitor

[1] OC Overcurrent protection
Problem The drive output current momentarily exceeded the overcurrent level.
OC1 Overcurrent occurred during acceleration.
OC2 Overcurrent occurred during deceleration.
OC3 Overcurrent occurred when running at a constant speed.
Possible Causes
(1) The drive output termi-
nals were short-circuited.
(2) Ground faults occurred
at the drive output
terminals.
(3) Loads were too heavy.
(4) The value set for torque
boost (F09) was too
large. (F37 = 0, 1, 3, or 4)
What to Check and Suggested Measures
CHECK
Check input voltage, output voltage and interphase unbalance.
SUGGESTED ACTIONS
– Connect a molded case circuit breaker, an ground fault circuit interruptor (with the exception of those
designed for protection from ground faults only) or a magnetic contactor.
– Check for voltage drop, phase loss, poor connections, or poor contacts, and fix them if necessary.
CHECK
Check if the jumper bar has been removed between terminals P1 and P (+) or if there is poor contact
between the jumper bar and the terminals.
SUGGESTED ACTIONS
– Connect the jumper bar to terminals P1 and P (+), or tighten the screws. Or connect a DC reactor.
– Replace the drive if it is malfunctioning.
What to Check and Suggested Measures
CHECK
Remove the wires connected to the drive output terminals (U, V, and W) and measure the interphase
resistance. Check if the resistance is too low.
SUGGESTED ACTIONS
– Remove the short-circuit (including replacement of the wires, relay terminals and motor).
CHECK
Remove the wires connected to the drive output terminals (U, V, and W) and perform a Megger test.
SUGGESTED ACTIONS
– Remove the short-circuit (including replacement of the wires, relay terminals and motor).
CHECK
Measure the motor current with a meter, and observe the current variations. Use this information to decide
if the current may exceed calculated design values for your system.
SUGGESTED ACTIONS
– Reduce excessive load or use a larger drive.
CHECK
Observe the current variations and check if there are any sudden changes in the current.
SUGGESTED ACTIONS
– If there are any sudden changes, make the load variation smaller or raise the drive capacity.
– Enable current limiting (H12).
CHECK
Check that the output current decreases and that the motor does not stall if you set a lower value than the
present one for F09.
SUGGESTED ACTIONS
– Lower the value for torque boost (F09) if the motor is not going to stall.
6-7