Interested to Buy Any Domain ? << Click Here >> for more details...
why neutral of 6.6 kv star connected sq. cage induction
motor does not get earthed, though for earth fault
protection it is must.
- 7 Answers
- 13492 Views
- I also Faced
- E-Mail Answers
Answer Posted / engr. l. o. osuji
Hi Pratikjain,
The answer in #4 is partly correct. Your question is on the
motor and not on the feeder. Provide appropriate cts and
wire correctly using an over-current earth fault relay.
Note, this relay has three operating elements known as red,
yellow and blue-phase elements. The yellow-phase element is
for earth fault. This relay works on the principle that Ir
+ Iy + Ib = 0 for a balanced load. This summation is
algebraic. In times of an earth fault the above equation is
no longer equal to zero hence the residual current flows
through the yellow-phase element as an earth fault provided
your cts and relay are properly connected. In this way the
cb for the motor is tripped by the yellow-phase element as
an earth fault if the relay is properly set.
| Is This Answer Correct ? | 2 Yes | 4 No |
Post New Answer View All Answers
difrent between vcb acb sf6 and mccb breakers
What is the different between conventional MCC and intelligent MCC? Common controller or controller for each bucket
How to calculate total harmonic distortion level(THD) in VFD? and how can we reduce harmonics?
Define availability (operational)?
How to synchronization will be done between two DGs ?
What is size 00, 01, 1 etc., in HRC fuse types?
i need mat lab program to find out the transmission line losses,regulation and losses
why incomer bay is required before transformer bay if there are more than 1 nos. of transformer bay.
Hi Suppose we have a wye/wye transformer which is grounded at both sides,in this situation, do we have ay ground transformer? in other words, ground transformer can do any thing more (while we have nuetral wire in both sides)? As the last question, what about 3rd harmonic? we have two choices: first using wye/delta transformer + ground transformer and second using wye/wye earthed connection.in the former choice, we dont have 3rd harmoonic at the secondary side but what about Yn/yn conection? do we suffer from 3rd harmonic in the Yn/yn connection?
why should the primary of transformer be connected in delta in a heat run test?
for 4 MVA , 33K.V/6.6K.V transformer. secondary side the connected load is 3000H.P. What is the rating of capacitor bank to be insttaled.
what is the meaning of impedance protected in instrument cooling fan
difference between the applicability of nortons and thevenin theorem
how to calculate insulation level of transformer?
What is the difference between Static and servo controlled voltage stablizer?
