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Neutral CT testing

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    Neutral CT testing

    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?
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    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.
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    Quote Originally Posted by bwillsey88 View Post
    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
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