i)Supply voltage is VL/root3 but supply current
i)supply voltage is VL=Vph but supply current
Both supply used in speed control of induction motor.
Transmission point of viwe delta is better.
Application point of viwe star is better.
1. It is a setup where in one end of each phase is
connected together so as to form a neutral.
2. It is used for variable loadings
3. The line current = Phase current
4. The Line voltage = sqrt(3)* Phase volatge.
1. It is a setup where in one end of one phase is joined to
starting end of another end so a ring is completed.
2. It is used for balanced loads.
3. There is no neutral in here
4. Line current = sqrt(3)*phase current
5. Line voltage = phase voltage.
line volt- voltage taken from two live wire= voltage taken
from one live neural connection
IN STAR CONNECTION THE LINE CURRENT EQUAL TO THE PHASE
CURRENT AND LINE VOLTAGE GREATER THAN PHASE VOLTAGE ,
VPH=VL/ROOT3 AND IN DELTA CONNECTION THE LINE CURRENT
GREATER THAN PHASE CURRENT , IL=IPH X ROOT3 AND LINE
VOLTAGE IS EQUAL TO PHASE VOLTAGE AND FINALLY BOTH
CONNECTIONS ARE VERY USEFUL IN THE 3 PHASE SYSTEM.
what happens when back feeding supply accidently collapses
with normal supply ??? How??
[that is sometimes in a substation 11kv feeder if their ws
long time permit work, back feeding supply will provide from
nearest substation... if accidently after the permit
work,they charged the feeder without removing back feeding
wat will happen...?]
There are two nos of 33Kv/11Kv 5MVA transformers conecting
through HT cable from substation having metering at
substation itself.One transformer used at a time another
remains stand by.Further 11 nos of 11Kv/440V transformers
are attached on it and each transformer is having its own
Power factor correction panel.Now one 33/11Kv transformer
at no load condition/Stand by condition is having power
factor in leading side upto 0.21 and while when another
tranformer at same situation have power factor in lagging
0.42. Now one thing is clear that transformer one is having
1.5 Km long 33kv cable due to that PF goes in leading side
and another is having only 250 mtr length remains him
lagging. Now i want to know that how i can maintain the
Power factor at no load/ stand by position though both are
behaving in seperate manner.