pandees Posts: 1, Reputation: 1 New Member #1 Nov 2, 2009, 08:13 AM
How to calculate the short time current rating for current transformer?
Respected sir's,

How to calculate the "short time current rating"(i.e-primary short time current rating-like if u take 400-400/5-15va/class1,40ka/3sec).

40ka/3sec-how to calculate this rating from the substation?

I am waiting for your's reply...

Thanks&regards,
pandees.b
 anasmemon Posts: 3, Reputation: 1 New Member #2 Mar 10, 2011, 01:43 AM
Short time rating is defined by your MVA rating. Suppose you are using 0.8MVA transformer at 33/11KV, so your STC will be 0.8*1000/(1.73*11)=42KA.

I hope this will help you. So to calculate STC the data you have given is not useful.. but system parameters are required.
 kkspwr Posts: 1, Reputation: 1 New Member #3 Jul 16, 2012, 11:00 PM
How much will be 6.6 /.4 kv transformer be equivalent in KVA
 tkrussell Posts: 9,659, Reputation: 725 Uber Member #4 Jul 17, 2012, 04:50 AM
Not enough information provided, assuming you mean the primary is 6.6kV and the secondaray is .4 kV.

Originally Posted by kkspwr
how much will be 6.6 /.4 kv transformer be equivalent in KVA
 surajkr123 Posts: 1, Reputation: 1 New Member #5 Jun 2, 2013, 09:40 PM
Study some electrical man , you are technically too weak to suggest , are you aware of % impedance?

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