Step Down Voltage; Current Limit - ABB PST Installation And Maintenance Manual

U
100%
Example 50%
30%
Stop
Figure 5: Step down
voltage for Stop ramp
U
100%
Fixed voltage
Reached set
level of current limit
30%
t1 t2
I
t1+t2 = set ramp time
5
Set level
of current limit
2
Figure 6: Current limit
122
AC 1006.9 - 5/03
Chapter 10 - Functions

10:6 Step down voltage

Path in menu:
Menu/SETTINGS/Functional Settings/
Start/Stop / Step Down
Initial voltage 30%
(=end voltage 30%)
When stopping a motor using the stop ramp, the speed will not
decrease immediately. The step down voltage function makes it
possible to set a level where the motor speed decreases as soon as
Time
the stop ramp begins. By using, a more optimized stopping of the
motor is achieved. It is mainly used for pump applications.

10:7 Current limit

Path in menu:
Menu/SETTINGS/Functional Settings/
Start/Stop / Current Lim
It is possible to limit the starting current by using this function. When
the current limit is reached, the output voltage stays stable until the
current level falls below the limit, then the ramping continues.
Time
The starting current must be high enough to make it possible for the
motor to reach the rated speed. The lowest possible current depends
on the performance of the motor and the characteristics of the load
Time
Parameter Default
text value
Step Down 100%
Parameter Default
text value
Current Lim 4.0 x I
e
Setting
Description
range
Voltage
value to
which the
softstarter
30...100% will step
down at stop
and where it
will begin the
stop ramp.
Setting
Description
range
Level of the
2.0... 5.0xI
e
current limit
Low Voltage Products & Systems
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