Gents
Many thanks for your support and comments, makes for Interesting reading, due to production demands we have not been able to shut this machine down yet, we plan to shut it down on 4th Feb when we will be able to investigate further
will keep you posted
Thanks to Marke and DanDel
To try and overcome the initial problem the run up time in star was reduced,surprisingly this actually helped the situation (avoided tripping) although we do not reach 90% speed prior to change over, Following taking the current readings this was one thing I was going...
d23
We have fitted standard motor rated contactors, we have been cautious with adjusting the switchover time, but I would expect to see the current spike in all 3 legs?
Thanks
We have a 75kw motor and recently replaced the all the contactors, following this when the motor ran up, it would trip the overload as soon as it switched to delta, If the motor had no load it switched over fine, we found by increasing the magnetic overload level the breaker will stay in under...