How would we calculate the no of earthing pits required
for motor /panel

Answer Posted / babloo

the no.of earth pits is usually calculated considering the
fault current, for suppose if the short ckt occurs b/w the
2 phases the fault current will be 3times to the normal
current. For example A 55KW motor carrying the current of
80A during normal running , when the short ckt occurs the
fault current has to dissipate through the earth, so the
earth must be around 25 X 3mm strip.

Is This Answer Correct ?    2 Yes 2 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

Why we use ups battery and dsdb battery in thermal power plant

1636


what will happen if the prime mover on the field excitation of the on-coming generator fails?Explain.

5008


what is rating boiler

1559


What is meant by derating factor?

668


list the type of vfd? wich is sutable for heating kiln?

1599






what are the standard IR values should be of R-E, Y-E, B-E, R-Y, Y-B, B-R of VCB in closed condition and in open condition for 500KVA & 1000KVA transformers. and what is the acceptable range when tested by 5000V megger.

1844


The power factor of the fixed load is 0.8, now the p.f is varying from 0.8 to 0.5.

1572


working principle of AC Servo Motor with its construction

8333


Define reserve-generating capacity?

648


How I calculate the ELCB for circuit breakers?

1657


How to decide DO set rating of Transformer?

1157


Dear Respected sir how to test ABB REX521 protection relay by relay tester.

2297


what is effect of 5amp fuse on 2mva pry protection of transformer

1364


what happen if drive input fail momentry at 48.5 HZ frequency?

1502


if we look on phasor of the transformer vaoltage is 180 oppsite at primary and the secondary so to improve a power factor is secondary should kept negative to improve it primary side means is -.90 became +.90 at other side

1389