how to estimate the breaker capacity of breaker,please give
the one example( 6.6 kv breaker,800a)?????
Answer Posted / raghavendran.r
Step1: Calculate the system MVA.I have calculated that as 1.732*6600*800 = 9.144MVA. I have taken it as 10 MVA for easy calculations further.From the system MVA find out the Fault MVA value using the per unit impedance.i.e
Fault MVA = System MVA /P.u.Impedance.I am taking iot as .1
Hence we arrive at the Fault MVA.From this condition we get to know the Short circuit current as Isc = Fault MVA/Sys Voltage(6.6kV).
Usually, for a 6.6 kV system, the short circuit withstand rating is 40kA for 1 second.The Momentary current or making current is 2.55 times the Max. short circuit current.hHence we arrive at 100kA(Peak)
| Is This Answer Correct ? | 2 Yes | 2 No |
Post New Answer View All Answers
What is the Load Capacity of Panther conductor (0.2) and dog conductor (0.2)
what is the use of the circle diagram
The size and construction of bushings in a transformer depend upon?
What is EMC filter in VVVF Drive ?
what is the difference between 50 hz freq. and 60 hz freq.? which is better and economic in them ?
what is the synchronous timer ? and it applications.
How do I calculate a WTI CT ofa 1250kVA 6600/400V transformer
Does the motor power displayed on the Motor name plate is the mechnical power motor delivers or it is consumed power from the system?
If mutual flux is 1.2wb & power factor is 0.8 lag , then what is the Useful flux of a transformer?
Why is it prefer to initiate circuit breaker failure by "86" lockout relay not by "94" tripping relay ?!
my name is venkat .i have good percentage in my academics(ssc 86, intermediate 83 b.tech 73) my question 1..after completion of my ssc i joined in bpc but i didnt got rank in emcet so i completed MPC in one year compartmentally ..so here what am expect question from this background?
difference between a diode and thyristor?
DEFINE BREAKING CAPACITY OF BUSBAR & HOW IT IS CALCULATED?
we have a rewind motor of 2Hp,2800Rpm, 220Volt AC. how can we choose the running capacitor for this motor, any formula for that?
WITCH CARDS IN USE IN FIRE CONTROL PANEL.