CT Primary Injection Ratio Testing Problems

CT Primary Injection

Situation after CT Primary Injection: New 230kv breaker Testing CT’s, 4000/5, by high current injection injecting 80 amps A phase to ground the secondary leads are shorted in a junction box A-B-C-N / additionally a voltage is connected to test instrument form test set The secondary readings are A = 0.096

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CT Primary Injection Ratio Testing Problems

Understanding Transformer Vector Groups

Transformer Vector Groups

Transformer vector groups can be a difficult concept to understand. I was lucky because the transformer ratio test-set I used for the first couple of years in my career allowed me to make three-phase connections, but it was really a single-phase tester and I had to change the connections  one

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Understanding Transformer Vector Groups

Potential Transformer Testing (PT/VT)

Potential Transformer Testing

I co-wrote an article for the NETA World magazine in 2004/2005 that covers several different manual techniques for potential transformer testing that explains several low-tech solutions for potential transformer testing.  I’m not sure if it was ever published because I can’t find it in the NETA world archives and it

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Potential Transformer Testing (PT/VT)

Current Transformer Testing (CT)

Current Transformer Testing

I wrote an article for the NETA World magazine in 2004 that covers several different manual techniques for Current Transformer Testing that should help even the most experienced technicians.  Here’s a summary of the current transformer testing paper. Back to the Basics – Current Transformer Testing (CT)  As test equipment becomes more

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Current Transformer Testing (CT)