Preventing Overvoltage By Automatically Reducing The Regenerative Torque Limit (Overvoltage Inhibit Function, Prg: 102 Only) - YASKAWA Varispeed G7 Instruction Manual

Setting Example
An example of stall prevention during deceleration when L3-04 is set to 1 as shown below.
Setting Precautions
The stall prevention level during deceleration differs depending on the Inverter capacity. Refer to the fol-
•
lowing table for details.
200 V Class
400 V Class
When using the braking option (braking resistor, Braking Resistor Units, and Braking Units), be sure to set
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constant L3-04 to 0 or 3.
To decelerate at a shorter time than the deceleration time set when L3-04 is set to 0 with the braking option
•
enabled, set L3-04 to 3.
The setting of L3-04 is ignored for flux vector control or open-loop vector 2 control.
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Preventing Overvoltage by Automatically Reducing the Regenerative
Torque Limit (Overvoltage Inhibit Function, PRG: 102
The overvoltage inhibit function is a function that, by reducing the regenerative torque limit to a value less
than its set value according to the main circuit voltage level, suppresses voltage rises with regenerative torque.
Using this function means that if, for example, the main circuit voltage rises during deceleration, the regener-
ative torque limit will be reduced and so the deceleration rate will be reduced automatically, suppressing rises
in the main circuit voltage.
This function is effective for suppressing overvoltages that occur during stabilization after an overshoot fol-
lowing sudden acceleration. This function differs from the stall prevention during deceleration function in this
respect.
This function is enabled during vector control.
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6
Output frequency
Fig 6.25 Stall Prevention During Deceleration Operation
Inverter Capacity
E1-01 ≥ 400 V
E1-01 < 400 V
Deceleration time controlled to
prevent overvoltage
Deceleration time
(set value)
Stall Prevention Level during Deceleration (V)
Time
380
760
660
only)