Harris Institute of Technical Training

Will a form 45s meter work in a single phase primary installation with 1 CT 1 PT.

Thanks for the question DW. The short and sweet answer to this question is:
A 4S meter will not correctly meter a single phase primary service without modification to the 4S meter current coils connection. If the coils in the 4S meter are not connected in series, then the metering is not correct (probably close to 50% of the correct billing). You should be able to use the 4S meter socket and wire it correctly for use with a 3S meter and this would be my suggestion to you to correct this.

The Form 45s(5s) meter not the 4s. the way we wire the 45s(5s) is by installing the voltage and current wires in series in the 8 terminal base and half the multiplier.

Sorry about that. I didn’t read the post carefully enough so I missed the 45s. For this to work correctly the meter potential coils must be connected in parallel and the current coils connected in series. If you have questions about the connection please let me know.