YASKAWA iQpump Series

102 YASKAWA TM.iQp.02 iQpump Drive Programming Manual
Figure 1. 86
Figure 91 Time Chart for Stall Prevention During Acceleration
The L3-02 parameter is set as a percentage of the iQpump drive rated output current. If the motor capacity is small compared to the
Drive’s capacity, or if the motor stalls during acceleration, lower the set value of L3-02.
■ L3-04 Stall Prevention Selection During Decel
The stall prevention during deceleration function adjusts the deceleration time in order to prevent OV fault trips during deceleration. If
L3-04 = “0: Disabled,” stall prevention is disabled and if the load is large and the deceleration time short enough the iQpump drive may
fault and stop.
If L3-04 = “1: General Purpose,” then the standard stall prevention function is enabled. If, during deceleration, the DC Bus voltage
exceeds the stall prevention level (see Table 27), the iQpump drive will discontinue decelerating and maintain speed. Once the DC Bus
voltage has dropped below the stall prevention level, the deceleration will continue down to the Speed Command level. See Figure 92.
Table 27 Stall Prevention During Decel
If L3-01 = “2: Intelligent,” the intelligent stall prevention is enabled. The active deceleration time is ignored and the iQpump drive will
attempt to decelerate as quickly as possible without causing the DC Bus voltage to exceed the stall prevention level.
The following figure demonstrates acceleration when L3-04 = “1 General Purpose”.
Figure 1. 87
Figure 92 Time Chart for Stall Prevention During Deceleration
Setting Description
0 Disabled
1 General Purpose (
factory default)
2 Intelligent
Drive Voltage Stall Prevention Level during Deceleration (V)
240 Vac 380
480 Vac E1-01 ≥ 400 Vac 760
E1-01 < 400 Vac 660
Output
Frequency
Output
Current
a - Set accel time
b - Accel time is extended
L3-02
t
a
b
t
a b
TIME
t
a
380/660/760 Vdc
t
Output
Frequency
DC Bus
Voltage
b
a - Set decel time
b - Decel time is extended
TIME