Answer / dhandapani muthu.r, je tneb, i

Unless otherwise it is discharged and earthed it should be
treated as energised. We have to discharge and eath that
bus or cable with a set of earth rods. Then only it is
proved. We could also use a remote sensor to prove that it
is dead.

Answer / rod

As we are dealing with high voltage it is critical that the
correct procedure is used. 1/ A switching sheet should be
used to ensure that both sides of the test point is
isolated locked and tagged, 2/ A Modiwak (HV sensor) should
then be tested on a known live source first then the
isolated point should be tested and the Modiwak should then
be retested on the known live source, this ensures that the
Modiwak is functional, 3/ Then dressed in the correct PPE
earths may be installed, making sure the the earths are of
a size for the fault level at that point.
All the previous answers are partly correct but to prevent
accidents it is esential that a strict procedure is used.

Answer / hassan

BOTH SIDES BREAKER OPENED , DE-ENERGIZED AND EARTH APPLIED.

Answer / giri

Nowadays we have got HT sensors which will give indication
when it is brought near the live bus bar.

Answer / kedar

After taking all the necessary steps to discharge the bus-bars even then u r not confirmed. Then you should use a special meter which works on induction principle which senses the magnetic field of the bus bar and will tell u whether the bus is discharged or not.

Answer / siddharth tayade

unless there is nothing any potential refrence to earth and
bus

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