Drive questions

We use sinamics S120 with CU310 for conveyor system of rollling mill(to tranport steel coil).
The system use sensorless vector control ?
During winter time we face lot of drive problem, mostly overspeed alarm,motor locked alarm.

Could anyone tell me whether temperature drop change drive behavior ? What we need to do then?
Do i need to again tune drive ?(more than 50 AC motors).
Your prompt reply will be great help.

The temperature will not affect the drives but it will have an have an effect on the mechanics. The friction is likely to increase as temperature drops but not by a great deal and I don't suppose it gets that cold in Dubai even in winter.

It sounds like the drive is not able to accelerate / decelerate the motor. You could try increasing the ramp times for accel and decel. Check that the drives are running in sensor less vector rather than V/F mode. Maybe redo the motor ID and see if that makes a difference.

Nick

Hi nick, Drives are running in sensor less vector control If I do only motor Id, do I need to do other testing ? if I increase ramp time do I need to retune too?

also could you please tell me, what criteria indicates current controller working properly. Also how you set P and I value of speed controller?

If you do a motor ID then don't forget to save the results or they will be lost when the drive is powered down.

The speed loop tuning is very down to experience.

Nick