We have 800KW motor operating at 6600Volt,50 Hz
supply.During 1st startup it tripped on overcurrent
trip.It's FLA is 88 Amps.The K factor of Thermal overloaaad
was set on .94 initially.then we set at 0.97 and then it
started fine.i dont understand why it tripped first?What
are the protections which comes in picture during starting ?
Answer Posted / parveen garg
I DO NOT KNOW ABOUT 6.6KV MOTORS & ALSO ABOUT K FACTOR.BUT
ACCORDING TO UR QUESTION IT LOOKS THAT MOTOR DRAW MORE
INSTANTANOUS CURRENT THAN ASSUMED BY THE CALCULATION & AT
THIS STARTING CURRENT OLR TRIPPED,WHEN U INCREASE THE
SETTING OF OLR.IT DO NOT TRIP.
FOR THE PROTECTION POINT OF VIEW ONE EXTRA CONTACTOR MAY BE
PROVIDE IN PARALLEL TO THE OPERATING CONACTOR WITH TIMER
WHICH WILL MADE OFF THE CONATCTOR(PROVIDED NEWLY)&ALSO THIS
CONTANCTOR WILL DRAW POWER FROM MAIN BUSBAR WITH EXTRA OLR .
Is This Answer Correct ? | 0 Yes | 5 No |
Post New Answer View All Answers
What are the advantages of vscf wind electrical system?
where lt & ht capacitor used
What do you mean by ratio correction factor of instrument transformer?
1)What is a Triode? What are its uses? 2) What is a Triac? 3) What is a Thyristor?
How select ELCB for 32amp. socket having quantity 12Nos. We have to do this wiring in PLANT. Please Also explain the incoming cable specification.
wat is the first thing dat is needed, 2 lay a cable in some area??
What is Traction? 1KVA Alternator, How much urrent taken?
HOW TO CALCULATE THE REGULATION OF 100 AND 25 KVA TRANSFORMER
what is a pilot wiring and whys that called a pilot wiers
electrical ques
Describe the control mechanism of missile launcher???
Can 4pole (3 phase+neautral )RCCB proper functioning in only 3 phase load (no neautral, no Earth) ?
Determine the BTU size of an aircon for 20 sq metre room
What will happen if we introduce negative feedback to a control system that uses a positive feedback?
What the difference between three phase contactor (coil 110vac) & three phase SSR (control voltage 110Vac)? May I use contactor in place of SSR?