I am an electrical power engineer and arranged power system
for a data center, I installed MCB, ELCB and erthing system
TN-C-S.
But some times several ELCBs Disconnect circuits at the
same time! what may be the reason? (the ELCBs are 25A ,30mA)

Answers were Sorted based on User's Feedback



I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / chandra

Mr. Mehdi, Do check the neutral of all circuits wether they
are connected to same ELCB group. If one neutral from one
group is connected to other group this problem will occur.
Even though all neutral is common at final point, each
neutral will have to pass through the ELCB in order to
monitor the return cuurent.

Is This Answer Correct ?    10 Yes 0 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / prashant

that means tgat u wer using those 30 mA ELCB to feed ur ac/
power sockets or some other heavier load

Is This Answer Correct ?    3 Yes 0 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / k.p.sharma

Mr.chandra & mehndi is right and the normally mA of ELCB
used IS AS BELOW:-

1. FOR DOMESTIC = 30MA
2. FOR COMMERCIAL BUILDINGS ETC = 100MA
3. FOR INDUSTRIES = 300MA

Is This Answer Correct ?    2 Yes 0 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / nageshwaran.n

Hi boss, check the connections properly.
Check for:
1. Total Load on MCB's. It should not exceed the market
rating.
2. For ELCB's, check the circuit for the leads interchange.

Is This Answer Correct ?    1 Yes 1 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / mehdi

there wasn't any Falctuation in cicuits. it is strange that
if any problem occured in one circuit others may not be
failed!
I solved my problem by replacing those ELCB with 300 mA
Type!

Is This Answer Correct ?    0 Yes 0 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / x man

TRY 100ma

Is This Answer Correct ?    1 Yes 1 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / pillay

the choice of 30 ma is correct,
or in fact we should be able to
decide what ma rating we want
to choose where.
It could be the fault current was
quite big but fault current could
not be grounded fast enough resulting
in the current floating into other
neighbouring cct resulting in triggering
of the elcb,s.The other solution would
be checking the grounding connections from
the earth pit to upwards and also the actual
earth resistance measurements.

Is This Answer Correct ?    0 Yes 0 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / prakash veer singh

Dear Mahdi
Some Current is leakege in earth form circuit and
equepment . so your ELCB was trip.so frist check the all
circuit .
you are using TN-C-S earthing .in this common earth use
for nutral and grounding .
I suggested you for use TN-S type earthing .

Is This Answer Correct ?    0 Yes 1 No

I am an electrical power engineer and arranged power system for a data center, I installed MCB, EL..

Answer / shriram.....

ELCBs Disconnect circuits at the power fluctuation time or
any other reason????

Is This Answer Correct ?    0 Yes 2 No

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