Dear Friends, I have a 500KVA transformer supplying whole factory having 3 p

Dear Friends,
I have a 500KVA transformer supplying whole factory having
3 phase and single phase mixed loads. Power room has
ammeters connected via CTs for individual phase. Now I know
that readings shown on meter for each phase say R,Y and B
are line currents. But when I want to know the total on
transformer do I need to add the currents of all three
phases readings shown on meter or value for anyone phase
will give me the correct power load on transformer for that
point of time.

2. If ammeter shows unbalanced readings for R,Y, B phases
say 150, 250 and 300 respectively so can I assume that 150A
i.e average of 3 will be the 3phase load currents and
remaining will be 1phase currents. Please clarify my doubt.

Question Posted / ansi

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Dear Friends, I have a 500KVA transformer supplying whole factory having 3 phase and single phas..

Answer / ahmadmukhtiar

1. The load of R, Y or B will be the total load on
transformer.
2. There must be phase balancing system for protection
otherwise the equipment connected as load will get damaged
if all three phases are unequal.

Is This Answer Correct ?

1 Yes

0 No

Dear Friends, I have a 500KVA transformer supplying whole factory having 3 phase and single phas..

Answer / k.prakashchandra

Calculate load(KVA) on each phase and add

Is This Answer Correct ?

1 Yes

0 No

Dear Friends, I have a 500KVA transformer supplying whole factory having 3 phase and single phas..

Answer / sakthivel

each phase you find consuming power with use ammeter reading
and volt meter reading
each phase you regulate the load current or equal load
current load you choose

Is This Answer Correct ?

2 Yes

2 No

Dear Friends, I have a 500KVA transformer supplying whole factory having 3 phase and single phas..

Answer / abdul karim

If you wants to know the total load of transformer , you must use a watt metrer , OR you will calculate the load in watts of every individual phase then sum of all three phases will be your answer.

Is This Answer Correct ?

0 Yes

1 No

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