how to calculate the megger values for motor, cables and
transformers?
Answer Posted / karan
The thump rule is voltage rating +1 example for a 11KV
motor it should be 11+1=12 Mega ohm.
In addition to that the PI is the ratio between 1Mnts and
10 mnts.It should be above 1.5
For examle IR at 1mnts= 10M.ohm,
IR at 10 Mnts= 20 M.Ohm
Then the Polarisation index is 2 which is consdierd
good.When it is below 1.5 you can heat the tranformer or
motor then the value will come up.
| Is This Answer Correct ? | 25 Yes | 4 No |
Post New Answer View All Answers
why we permissive overreach in distance protection.where it is applicable to use in long r short lines
what is excitation/
What is difference and reason b/w -48V BTS system and 24 V BTS system. Plzzzzzzzzz tel me.
what is the IEC standard for Power Cable installation in onshore (like in direct buried ground or above groung)
What is dc current source?
how to find ratio of CT & PT in 66/11kv 12 mva supply system ? explain with calculation.
What is transformation ratio what it describes?
What happens if the series current double?
The synchronous machine excitation system explain
What is cross over distortion? How it can be eliminated?
3phase motor can be used as a Prime mover for alternator.
What is center gravity load in substation?
is there any role of power factor with frequency variation? and how we can manage the frequency variation?
What is knee point voltage of transformer?
Please brief what is sinewave