I have carried out wiring for lighting in a shed in Industrial area which cont

I have carried out wiring for lighting in a shed in
Industrial area which contains Metal halide lamps & have
balanced in 3ph.Now when we put all the lines on in the
daytime the current taken at 3phases at MCB comes to be
equal i.e.28,29,28Amps respectively but in the night time
i.e between 7p.m.to 11p.m. at the same MCb the current is
52,59,62Amp, though I have fit 63A MCB it is tripping in
the above period.What may be the reason.?
Note: This industry is located in industrial area where
majority of steel ingot manufacturing plants are there.
Whether this may be due to harmonic? what should I do to
overcome above problem.pl suggest urgently.

Question Posted / makarand

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I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide la..

Answer / ankurjha

May be some other load is coming in line at night time. see
for unautherized taps in line..

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I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide la..

Answer / karthik

better change all mh fitting to other energy efficient
fittings atleast change the copper wound ballast to
electronio ballast

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I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide la..

Answer / h r jadhav

pl check the maloperation of mcb or correct rating of mcb/
secondly the power factor may be very low of the metal hal
lamps during day time that may be compenseted by bus
capacitors and which are disconnected at the time of no
work. there by increasing current and mcb get tripped/ pl
use energy efficient electronics ballast.

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I have carried out wiring for lighting in a shed in Industrial area which contains Metal halide la..

Answer / k.prakashchandra

You should allow 5% to 10% tolerance for MCB and
meters.There could be temporary additional load also.

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