YASKAWA iQpump Series Programming Manual page 102

Figure 1.86
Output
Frequency
Output
Current
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
■
Setting
0 Disabled
1 General Purpose ( factory default )
2 Intelligent
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
voltage has dropped below the stall prevention level, the deceleration will continue down to the Speed Command level. See
Drive Voltage
480 Vac
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
Output
Frequency
DC Bus
Voltage
102
a a
Figure 91 Time Chart for Stall Prevention During Acceleration
Table 27), the iQpump drive will discontinue decelerating and maintain speed. Once the DC Bus
Table 27 Stall Prevention During Decel
240 Vac
E1-01 ≥ 400 Vac
E1-01 < 400 Vac
a
Figure 92 Time Chart for Stall Prevention During Deceleration
t
b b
TIME
t
Description
Stall Prevention Level during Deceleration (V)
b
TIME
YASKAWA TM.iQp.02 iQpump Drive Programming Manual
a - Set accel time
b - Accel time is extended
L3-02
380
760
660
a - Set decel time
b - Decel time is extended
t
380/660/760 Vdc
t
Figure 92.