Importance of energy meter accuracy on the photovoltaic system monitoring

Monitoring photo-voltaic (PV) power plant is important to evaluate the performance of a PV system. Performance ratio is a method to calculate the performance a PV system. This method is comparing the actual energy output with the theoretical energy output. In general, In general, the actual output energy is measured at the inverter that connected to the load or can also use an external energy meter at the PV system output. The use of an external energy meter needs to be monitored because its function continues to decline and needs to be calibrated to restore its function to maintain the accuracy. This paper describes the calibration method to maintain the accuracy of energy meter. The accuracy of energy meter is important things to determine the performance ratio of PV system.