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Video: What causes an StF fault on an Altistart 22 Soft Starter?

Troubleshooting StF Fault on Altistart 22

Product Line:
ATS22 Soft Starter

All models

The StF fault means the starter has exceeded the maximum start time setting, tLS, in the SEt menu.  

tLS needs to be set higher then the ACC time.   For example:  If ACC ramp up time is 10 seconds, then set the tLS max starting time to 20 seconds.
If ILt current limit is too low, the motor may not reach full speed within tLS limit.
Mechanical problems on the load may prevent the motor from reaching full speed within tLS limit.
See page 51 in the attached ATS22 Programming Manual:

The following video is a guide for troubleshooting the StF fault code, indicating a longer than expected start-up time, on the Altistart ATS22 soft starter by adjusting the tLS (maximum start time in seconds) and ACC (ramp up time) parameters under the SET menu. tLS must be set higher then the ACC time value.

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