Yaskawa E7 Drive User Manual - Manual (Page 117)

Programming 5 - 43
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 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 below), the 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 below.
If L3-01= “2: Intelligent”, the intelligent stall prevention is enabled. The active deceleration time is ignored and the 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”
Fig 5.34 Time Chart for Stall Prevention During Deceleration
L3-05 Stall Prevention Selection During Running
Setting Description
0 Disabled
1 General Purpose (factory default)
2 Intelligent
3 Stall prev w/R
Table 5 Stall Prevention During Decel
Drive Voltage
Stall Prevention Level during Deceleration
(V)
240Vac 380
480Vac E1-01 ≥ 400Vac 760
E1-01 < 400Vac 660
Setting Description
0 Disabled
1 Decel Time 1 (factory default)
2 Decel Time 2
t
a
380/660/760 Vdc
t
Output
Frequency
DC Bus
Voltage
b
a - Set decel time
b - Decel time is extended
TIME
TM_E7_01_07182008.book Page 43 Wednesday, July 23, 2008 2:35 PM