Question { Alstom, 4575 }

My switchgear busbar is rated at 2000A and just imagine the actual load on busbar is 1000A. From that busbar there are 10 outgoing feeders. Now the question is will the load be 1000A on each outgoing feeder or 100A per outgoing feeder. 2nd thing how do i calculate the load on individual feeder. Thanks for your time. Please provide some clarification on this issue.

Answer

Dear
2000a is the total capacity of your bus bar.from that
busbar there will be onather taping according to your
switchgear rating like if you have 10 outing and three in
among of them is capacity of 250 Amps and rest of 100 amps
then your three feedar will conect with 250a acapacity
busbar & can take max 250 AMP and the rest will connect
with 100 A Bus Bar so it can take 100 Amps max very simple
it all depends on your switch gear rating

Question { 4637 }

an off load but energized 11/0.4 KV, 1250 KVA T/F has a
power factor of 0.65(capacitive)..!! why is it so, though
T/F being an inductive device ??

Answer

Dear
It is not possible. As the transformer is a inductive
device it can only lead to Lagging PF although it is idle
but there was definitely Lag PF the one possibility is that
the transformer is feeding to capacitor panel and because
it is off load so the resulting PF is Leading second thing
can happened that PF relay not working in auto made and
somebody has connected direct capacitor without calculating
the required KVAR to maintain transformer off load PF

Question { Wipro, 93749 }

what is the safety of ACB & VCB and how can this work and
how can the service the ACB & VCB parts name with picture

Answer

As you all knows that all circuit breakers can be called
as on off switch with some safety device ie ACB make and
break contact in air (one moving and one sliding) so it
called air circuit breaker for safety we use in ACB Under
voltage shunt trip closing unit. CBCT for tripping command
relay with over voltage earth fault etc for spring charge
we use motor charging mechanism. Same case with VCB
contacts makes in vacuum to minimize the arc during make
and break contact (one moving and one sliding) on high
voltage other function are same but according to the
voltage rating

Question { NTPC, 5563 }

Is 3C x 2.5 Sqmm Cable can withstand 40Amp Starting current?
If Yes then specify your ans.

Answer

YES
It can carry 40 Amps starting current as it is only for few
second but because of the over current the wire insulation
get thermal shock (during heating and cooling)and wire
insulation life will be decrease.