Dear all,
We have this big motor for our upcoming project(conceptual stage). What would be the most suitable operating voltage for it. Assuming that its starting method is Direct-on-Line (DOL). Our available operating voltages (at 50Hz) are:-
a) 3.3kV
b) 6.6kV
c) 11kV
Is it advisable to use...
Hi rhatcher & Others,
When we simulated a power failure, the genset kicked in and changed over from normal switchboard to emergency without a problem. Then when we manually ( no auto restart/reacceleration) energised the 160kW load breaker, the load breaker remained in contact for 1-2 seconds...
Hi,
I have a standy generator set rated 950kVA 415V 50Hz. Recently we tried to commission the genset with the biggest load being 160kW (first block). However, the load cannot be transfered to the genset. The load is using Direct-on-line (DOL) starter. The allowable voltage dip during starting...
Dear Teco & r2d2,
Thanks for your responses.
If the said motor construction is designed based on class F insulation (IEC 72 & 72A) use to Class B temperature rise, will the 103% operating current still affects the life span of the motor even though with the service factor of 1.1 and runs...
Hi,
I have a 200kW air compressor motor operating at 415V 50Hz drawing a current of about 103% of the full load current(FLA). According to the manufacturer, the motor has a service factor of 1.1. Obviously the current is still within the allowable service factor. Can I run this motor...
Hi,
We had about 30 of the above failed within a short time span on a single switchboard.We found out that some components on the auxilliary card of the relays burnt. We thought that is due to over-voltage on a particular phase only(in this case yellow phase). Is it possible? There was no...
Hi,
I have the above rated motor (1500 rpm) to start. Due to limited power availability from the Utility company, I cannot start the motor with more than 300% of full load current. Direct-on-line(DOL)is out of the question. I am looking at the possibility of using soft starter. However, the...
