Recent content by JatTiw

Application is for centrifuge pump in refinery. Electricpete & Edison123 thanks your support & shedding light on the issue. Best Regards

From PdMA test, the %age imbalance in resistance & inductance are 0.78% & 3.65%.......Looks like OK to me. Also please help me under stand why high efficiency motors will have high inrush as compared to normal motor. My thoughts were other way around.

As per manufacturer, LRA-1085. Instantaneous trip at breaker is already set to maximum, cannot go above what code allows.

I have Siemens make 150hp (164FLA), 460V motor (IEEE-841, premium efficiency) is causing main HMCP to trip on start-up. PdMA results shows all OK (PI-10; DDA-1.9; Average Phase resistance & inductance 0.0635ohm, 2.008mH) Inst. Breaker set at 13*FLA. No problem with cable or starter. Is motor...

Like I mentioned in 1st thread, Only one machine has the problem, Other work fine.

No mechanical/maintenance type issues. New brushes/slip-rings/holders installed 3-4 weeks back. Enclosed & instrument air for cooling. Each time set of brushes on ‘-ve’ terminal develop spark.

I have two identical 4000hp Synchronous Motors operating reciprocating compressors. The ‘–ve’ terminal brushes on one machine tend to develop spark. The excitation control system (GE-Stat-x-ator) has almost the same volts/amps/pf for each machine, as the loading is identical. Need help to find...

All these feeders has Delta/Wye transformers (with low resistance grounding) connected to it and has no capacitor banks, non-linear loads (ASDs etc) or surge arrestors.

I need help to solve a puzzle where some of the feeder breakers for healthy circuit were tripped cause of fault in one feeder, connected to same bus. Problem started with failing of few capacitors of capacitor bank and caused the tripping of capacitor bank feeder breaker on 3-phase instantaneous...

I need help to identify the difference between distribution class and power class bushing for power transformer Thanks

Hi jghrist, HL rating is CSA designation for cables installed in electrically hazardous location (Class-1 Div/Zone 1 etc) & FT is fire test rating for cable comment,

Is there any problem for getting HL & FT rating for un-armoured cables also? Cause cable I am specifying un-armoured cables.

Thanks mpparent, do you have any contact info at Okonite

Hi Every body I am looking for Three (3) copper conductor, 350 MCM, 15 kV, 133% insulation level with semi-conducting thermosetting layer as well as metallic tape, cable with EPR (Ethylene Propylene Rubber) insulation, shielded and PVC jacketed, HL rating & flame test-rating FT-4, CSA approved...

Hi Every-body, The API 541 deals with motors above 250hp in Petroleum & chemical industries. The question I have is which API or any other standard deals with motors below 250 hp in Petroleum & chemical industries.