My project concerns a 50KW 3 phase 120/208 volt photovoltaic inverter system that Im about to install. The Electric Utility uses 400A. polarized 1 turn CTs for their metering. The drawings included show only 1 phase for simplicity.
Previous installations have worked as shown in figures A and C. Figures A and C show power back fed to the Utility Grid when pv production exceeds the building consumption and thus turns the Utility Meter backwards. When building consumption exceeds pv production, the Utility Grid needs only to supply any additional power for the load not supplied by the pv system. This reduces power supplied from the Utility Grid.
My question is will I achieve the same metering results by making the connections as shown in figures B and D ? Does the stronger magnetic field of the conductor carrying more current cancel or retard or modify the lesser current carrying conductor, or vice versa ? Do the different directions the two currents travel through the CT nullify anything ?
http://home.comcast.net/~steve5x5/ct a-b2.BMP
http://home.comcast.net/~steve5x5/ct c-d2.bmp
Previous installations have worked as shown in figures A and C. Figures A and C show power back fed to the Utility Grid when pv production exceeds the building consumption and thus turns the Utility Meter backwards. When building consumption exceeds pv production, the Utility Grid needs only to supply any additional power for the load not supplied by the pv system. This reduces power supplied from the Utility Grid.
My question is will I achieve the same metering results by making the connections as shown in figures B and D ? Does the stronger magnetic field of the conductor carrying more current cancel or retard or modify the lesser current carrying conductor, or vice versa ? Do the different directions the two currents travel through the CT nullify anything ?
http://home.comcast.net/~steve5x5/ct a-b2.BMP
http://home.comcast.net/~steve5x5/ct c-d2.bmp