[cvander]

Good day. The control panel is a Y/Delta starter. If the motor runs in one direction it runs fine, but as soon as motor direction is turned around, all the contactors fall out as soon as it goes into delta run mode.I have megger tested the motor, it is 100% clear, coils have same resistance... everything is good. But it just won't run in both directions, I tried running the motor without any attached load, still the same result?Control circuit have mech and elect interlocking, I have checked for loose connection, burned contacts points,everything is as it should be. Disc motor and tested only control circuit, everything works fine... The control circuit is protected by fuses,motor does not blow fuses, only all the contacters fall out at once when going into delta in only one direction.. What can the problem be, I believe it's the motor, but there is no evidence?

[tkrussell]

Are the overload heaters for both forward and reverse of the correct setting?

[cvander]

There is only one overload on the main contactor, and yes I checked it, it's the correct setting. Also the problem does not trip the o/l, it only kicks out all the contactors ? Thank you