Can you please settle a professional dispute! A subcontractor is supplying a hydraulic powerpack driven by 3 x 3 phase 50Hz induction motors. We tested them at 50Hz and recorded current readings, my arguement is that this will reduce at a higher frequency. I base this on the inductive reactance...
Thanks for all the advice. I had the techs wind up the magnetic protection of the local breaker to maximum and change the upstream breaker with one that gave the proper discrimination. So far so good! I will know in future to allow for transition transients with a star/delta starter. Thanks.
The loading is affected by a timer from the compressor controller which allows ample time for the motor to be connected in delta. However I am not convinced that there is not residual air or excessive oil in the compressor rotors which is given a light load condition. I think this is the cause...
Thanks for the advice. The techs are ongoing with their investigations although they have reported another problem! On start up in star the current peaks at its maximum for around 3-4 seconds which I think is slightly to long. I know the motor will develop enough torque to overcome the load...
Hi,
We have installed a new star/delta starter panel for a 185KW motor which drives a compressor. Occasionally the main breaker trips on the transition from star to delta. We have experimented with the timer to try and achieve the optimum time to lessen the current and voltage effects on...
