ABB PST Series - 10:7 Current limit

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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 the stop ramp begins. By
this, a more optimised stopping of the motor is achieved
and it is mainly used for pump applications
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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.
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Step Down 100% 30...100% Voltage value to
which the soft-
starter shall step
down at stop and
where it shall
commence the
stop ramp.
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Example 50%
Stop
Time
Initial voltage 30%
(=end voltage 30%)
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Current Lim 4,0 x I
e
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Level of the
current limit
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Fixed voltage
Reached set
level of current limit
t1+t2 = set ramp time
Set level
of current lim
it
Time
Time