Analysis of Electrical Power Measurement Towards an Error in Current Transformer Wiring

The electrical energy is measured using a kWh meter exclusively provided by PLN, which must be installed properly and accurately. An error in its wiring process can have a fatal impact because it affects the calculation of the electrical energy being consumed. This study examines the electrical energy measurement errors in current transformer wiring. A Calmet TB40 SN.29819 CB 300B testing bench, an EDMI Mk10E Class 0.5S kWh meter, and a 100/5A current transformer were used as supporting equipment. Test procedure for the fundamental current was done at 100% load, 230 volts voltage, 5 impulses, power factor of 1, and 50 Hz frequency. The three testing environments were normal condition, reversed polarity condition of current transformer, and two of the secondary transformers being disconnected to the kWh meter. The test result under normal condition showed 69 kW active power with the kWh meter's error at +0.20%. Under the reversed polarity condition of current transformer, the test result showed 69 kW of active power with the kWh meter's error at +0.23%, which indicates that the measurement of electrical energy or power was under normal circumstances. Meanwhile, on the disconnected secondary transformer condition, the test result showed 62.84 kW active power with the kWh meter's error at -8.62 % which suggests that the measurement of electrical energy or power was abnormal.