Avoiding Overvoltage Tripping; Overvoltage Limit Operation - Toshiba TOSVERT VF-nC3 Instruction Manual

6.12.4 Avoiding overvoltage tripping

 : Overvoltage limit operation
• Function
These parameters are used to keep the output frequency constant or increase it to prevent
overvoltage tripping in case the voltage in the DC section rises during deceleration or varying speed
operation. The deceleration time during overvoltage limit operation may increase above the
designated time.
Overvoltage limit operation level
Output
Frequency
DC Voltage
[Parameter setting]
Title

Overvoltage limit operation


(Slowdown stop mode selection)
If  is set to 2 (quick deceleration control), the inverter will increase the voltage to the motor (over-
excitation control) to increase the amount of energy consumed by the motor when the voltage reaches the
overvoltage protection level, and therefore the motor can be decelerated more quickly than normal
deceleration.
If  is set to 3 (dynamic quick deceleration control), the inverter will increase the voltage to the
motor (over-excitation control) to increase the amount of energy consumed by the motor as soon as the
motor begins to slow down, and therefore the motor can be decelerated still more quickly than quick
deceleration.
During overvoltage limit operation, the overvoltage pre-alarm (  blinks) is displayed.
 is parameter for maker settings. Do not change this parameter.
Over-voltage stall protection level
Function
0: Enabled
1: Disabled
2: Enabled (Quick
deceleration control)
3: Enabled (Dynamic quick
deceleration control)
F-29
Adjustment range Default setting
E6581595
6
2