YASKAWA CIPR-GA50UВ001AJ Series Installation & Primary Operation page 135

Code Name
ov Overvoltage
YASKAWA TOEPC7106170YB YASKAWA AC Drive GA500 Installation & Primary Operation
Causes
If the drive detects the fault at
start or in the low speed range
(10% or less) and n8-57 = 1
[HFI Overlap Selection =
Enabled] for PM Control
methods, the high frequency
injection gain is too high.
The deceleration time is too
short and too much regenerative
energy is flowing back into the
drive.
The acceleration time is too
short.
The braking load is too large.
There are surge voltages in the
input power supply.
The drive output cable or motor
is shorted to ground (the current
short to ground is charging the
main circuit capacitor of the
drive through the power
supply).
15 Troubleshooting
Possible Solutions
• Set E5-xx [PM Motor Parameters]
correctly or do Rotational Auto-
Tuning.
• Decrease the value of n8-41 [HFI P
Gain] in 0.5 unit increments.
Note:
Set n8-41 > 0.0 for IPM motors.
• Increase the values set in C1-02, C1-
04, C1-06, or C1-08 [Deceleration
Times].
• Connect a dynamic braking option to
the drive.
• Perform Deceleration Rate Tuning.
• Make sure that sudden drive
acceleration does not cause the fault.
• Increase the values set in C1-01, C1-
03, C1-05, or C1-07 [Acceleration
Times].
• Increase the value set in C2-02 [S-
Curve Time @ End of Accel].
• Set L3-11 = 1 [Overvoltage
Suppression Select = Enabled].
Connect a dynamic braking option to the
drive.
Connect a DC link choke to the drive.
Note:
If you turn the phase advancing
capacitors ON and OFF and use
thyristor converters in the same
power supply system, there can be
surge voltages that irregularly
increase the input voltage.
1. Examine the motor main circuit
cable, terminals, and motor terminal
box, and then remove ground faults.
2. Re-energize the drive.
135