Yaskawa F7 Drive Programming Manual - Manual (Page 131)

Programming 123
The following figure demonstrates acceleration when L3-05 ≠0.
Fig. 88 Time Chart for Stall Prevention Level During Running
The L3-06 parameter is set as a percentage of the Drive rated output current. If the Drive still faults when L3-05 ≠0, then either
lower the L3-06 or adjust the C1-02 or C1-04 settings for a quicker deceleration.
L3-11 OV Suppression Function Selection
L3-12 OV Suppression Function Voltage Level
Setting Range: 350 to 390 Vdc (240V Class), 700 to 780 Vdc (480V Class)
Factory Default: 380Vdc (240 V Class), 760Vdc (480V Class)
This function suppresses a rise in the DC bus voltage caused by applications that have a cyclic regenerative load. This is
accomplished by lowering the regenerative torque limit in response to a rise in the DC bus voltage level. Parameter L3-11
enables or disables OV suppression function. When the DC bus voltage is less than the L3-12 minus 30Vdc level, the
regenerative torque limit value remains as set. If the DC bus voltage equals the L3-12 minus 30Vdc level, the regenerative torque
limit value is cut in half. If the DC bus voltage exceeds the L3-12 level, the regenerative torque limit is set to zero. Between the
L3-12 minus 30Vdc and L3-12 levels, the regenerative torque limit value is reduced in proportion to the DC bus voltage.
The OV suppression function is enabled only for open loop vector and flux vector (A1-02 = 2 or 3). This function should be
disabled for applications requiring precise speed regulation or precise stopping times as the motor speed could change based on
the reduced torque limit. Use a dynamic braking transistor/resistor instead to dissipate the regenerative energy. This function
works best when the motor operates in its constant torque area.
Setting Description
0 Disabled (factory default)
1 Enabled
a
L3-06
t
Output
Frequency
Output
Current
b
a - Decel time
C1-02 or C1-04.
b – Active accel time
t
b a
a - Decel time
C1-02 or C1-04
b - Active Accel time
TIME