how can we select the rating of Load break switch that is connected to
the primary protection of 200 kva 11kv/415v distribution transformer??
step by step calculated answr pls...thnk.u

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how can we select the rating of Load break switch that is connected to the primary protection of ..

Answer / guna

Depends up on the load current we have to select the LBS
instead of VCB or SF6 (LBS is less cost for the same rating
when compared to the above cb's)

P=1.732*V*I
I = P/1.732*V
I = 200KVA/1.732*11KV
I = 10.49 A

Is This Answer Correct ?    3 Yes 2 No

how can we select the rating of Load break switch that is connected to the primary protection of ..

Answer / kirn

Thank u guna sir for your answer. but the 10.49A is the
primary side current right?so after finding the primary
current,how many times of the primary current should we take
to find the breaker size??

Is This Answer Correct ?    1 Yes 2 No

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