Yaskawa G5 OV Suppression - Manual (Page 6)

Date: 07/01/04, Rev: 04-07 Page 6 of 8 TM.G5SW.017
P1-04 Over Voltage Prevention Frequency
Reference Gain B B B B
OVP Fref Gain
P1-04= 0.050
The Over Voltage prevention frequency reference gain value is used to convert the DC
bus overshoot into the frequency added to accelerate the drive preventing regeneration.
The added frequency may be monitored using U1-53: OVP Frequency. The DC bus
overshoot is equal to the DC bus voltage – (DC bus filter + P1-03: Deadband). This
value may be monitored using U1-51: DC Bus Overshoot. The DC bus overshoot is
multiplied by P1-04: Fref gain which yields the frequency to be added to the frequency
reference and may be monitored using U1-53: OVP Frequency. The sum of the
references may be monitored using U1-54: Total Ref. The drive follows this reference.
Example:
If the DC bus overshoot is 20 volts, the drive would add 1.0 hertz to it’s output. (20 volts
x 0.050 gain = 1.0 Hz)
P1-05 Over Voltage Prevention Frequency Limit B B B B
OVP Freq. Limit
P1-05= 5.00 Hz
The OVP frequency limit is the maximum OVP frequency that may be added to the
frequency reference accelerating the drive to prevent regeneration. The actual
frequency being added may be monitored using U1-53: OVP Frequency.
P1-06 Over Voltage Prevention Deceleration Start
Voltage B B B B
OVP Dec Start
P1-06= 700 Vdc
The OVP Deceleration Start voltage parameter is the DC bus voltage level where the
deceleration rate starts increasing to prevent the DC bus voltage from climbing higher.
Recommended settings for different voltage units:
230 VAC – P1-06 = 300 VDC
480 VAC – P1-06 = 700 VDC
575 VAC – P1-06 = 950 VDC
Setting Range: 0.000 to 1.000
Factory Default: 0.050
Modbus Address: 0x583
Setting Range: 0.00 to 10.00 Hz
Factory Default: 5.00
Modbus Address: 0x584
Setting Range: 200 to 810 Vdc
Factory Default: 700
Modbus Address: 0x585