Sorter Under Speed Alarm:

Typical Intelligrated sliding shoe sorter logic incorporates an alarm for under speed detection that indicates insufficient cycle counts (typically at start-up) at the first divert photoeye or setup switch photoeye.

If inspection of the first divert photoeye is not revealing any significant interference, Intelligrated recommends performing sorter diagnostic photoeye detect test.

On most Intelligrated systems, this test continuously compares cycle counts at the first divert photoeye with the remainder of the lanes. Different screens show different results, either in relative counts or absolute counts at each lane. In either case, problems with the first divert photoeye should cause some kind of failure in the photoeye detect test.

This will detect a true under speed condition (VFD not getting up to speed), but the error threshold is typically between 1/3 and 2/3 of the expected cycle count sample measurement. Therefore, for a drive to cause the error, the speed would be dramatically lower than normal and visibly incorrect. If a sorter appears to be at normal speed, the sorter VFD is not likely the cause.

1- login to momentum UI for the control Panel you have issue with 

2- Navigate to I/O Diagnostics 

3- locate drive control word output 

4- if it showing  00 00 00 00 force the byte to 00 10 00 00 

5- remove the force and ask site to restart the drive to verify the speed 

Note : site need to verify the drive parameter along with that 

This issue often happens due to power outage or power blip

Old ticket for refence :  TS-00446172 , TS-00444486 , and TS-00471493