How can to increase the ramp time of a motor being started by an ATS48 Softstart?

Issue:
ATS48 seems to ramp the motor  up more quickly than my ACC (acceleration) ramp time in the SEt menu?

Product Line:
ATS48

Environment:
ALL

Cause:
Programming/application

Resolution:
By default the ATS48 is programmed to ramp the torque in the motor.
However, if the motor is lightly loaded it may reach full speed before it reaches full torque causing it to appear that the ACC time is ignored.
If this is an issue, we can disable the torque control by setting  CLP :Torque Control (in the drC menu) to OFF.

The softstart will then simply ramp the output voltage to the motor.

It's still possible the motor will reach full speed before it reaches full voltage.  If that is the case, try reducing ILt : Current Limit to see if it helps, although setting ILt too low may cause the softstart to be unable to ramp the motor.
.
If precise Acceleration is required for the application, it is better to use a Variable Frequency Drive since we have much better control of the motor voltage and frequency.

If changing CLP to OFF causes issues starting the motor you may need to  enable bSt the voltage boost.


Consult the ATS48 User manual for additional information: https://www.se.com/us/en/download/document/1494409/

Released for: Schneider Electric Canada