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Current Transfomer (CT) ratio setting on energy meter

Current Transfomer (CT) ratio setting on energy meter

Current Transfomer (CT) ratio setting on energy meter

(OP)
I am using a smart energy meter which allows me to set the CT ratio among other parameters. I am using 50/5 ratio AC CT's. For the meter to do the kwh calculation correctly, I believe I have to set primary CT ratio to 50 and secondary CT ratio to 5. Now, if I have two rounds of the same 120 volt wire passing through the same CT, then I would set secondary ratio to 100. My question is, will this be equivalent to have just one round of wire through the CT and the primary ratio set to 50 , i.e the kwh calculated by the meter will still be right and I would'nt have to do any manipulations on the values obtained from the meter.

Meter Data sheet:
http://www.elmeasure.com/downloads/pg_5310.pdf

RE: Current Transfomer (CT) ratio setting on energy meter

50:5 with two passes on the primary is 25:5
One pass- 50:5, 50 Amps primary = 5 Amps secondary.
Two passes, 25 Amps primary = 5 Amps secondary.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Current Transfomer (CT) ratio setting on energy meter

You are confusing things by referring to a CT primary ratio and secondary ratio. The meter inputs are the CT primary rating and the CT secondary rating. With 2 passes, the CT primary is 25. The CT secondary is 5. The ratio is 25:5.

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