Installation manual

Detected Fault Management Parameters
128 S1A53838 09/2011
F305 [Overvoltage fault]
Overvoltage protection - 2
0
1
2
3
[Enable]
If parameter F305 is set to 0, and the drive detects an impending DC bus overvoltage, it will automatically take one of the fol-
lowing actions:
Increase the deceleration time
Keep the motor at a steady speed
Increase the motor speed
[Disabled]
If parameter F305 is set to 1, the drive will take no action to avoid a DC bus overvoltage.
[Quick deceleration]: Enabled (quick deceleration mode)
If parameter F305 is set to 2, and the drive detects an impending DC bus overvoltage, it will increase the V/Hz ratio of the
power applied to the motor. Motor over-excitation is used to dissipate regenerative energy into the motor instead of the drive.
[Dyn. deceleration]: Enabled (dynamic quick deceleration mode)
If parameter F305 is set to 3, the drive will increase the V/Hz ratio of the power applied to the motor as soon as slow down
begins instead of waiting for the DC bus voltage to approach the detected fault level.
When motor speed is being reduced, a DC bus overvoltage can often be caused by regenerated energy being absorbed by the
drive from the load and motor.
F626 [Overvoltage level]
100 to 150 % of nominal DC
bus voltage
140%
Parameter F626 sets the DC bus voltage level at which the actions defined by parameter F305 take place. See
diagram above for more details.
Code Name / Description Adjustment range Factory setting
Output
Frequency
DC Bus Voltage
: Over-Voltage
detected fault Operation Leve