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bwillsey88
April 26, 2017, 04:05 PM
Was testing some Nuetral CT's in new gear the other day and I was getting some ratio numbers that were a bit off. Bossman told me to disconnect the ground bound between the neutral and ground buss. I got good numbers after that. Anyone know why I was getting number that were about a 3% difference?

SecondGen
May 1, 2017, 02:46 PM
How did you have your test leads setup? Its possible that the current on the neutral bus was splitting depending on your configuration. This could cause your secondary current to be less than expected because not all the test current is flowing through the CT.

Vernon
May 18, 2017, 10:32 AM
Was testing some Nuetral CT's in new gear the other day and I was getting some ratio numbers that were a bit off. Bossman told me to disconnect the ground bound between the neutral and ground buss. I got good numbers after that. Anyone know why I was getting number that were about a 3% difference?

The connection may have resulted in stray current flowing through the CT.

www.cttestset.com