Electric energy is an essential component of modern life, making measurement accuracy crucial, particularly in billing systems based on kWh meters. This study aims to analyze
the measurement error level of three-phase postpaid kWh meters, both analog and digital, tested at the PLN UP3 Menteng Calibration Laboratory. The testing method employed a calibration device, namely the Calmet C300B. Data collected included voltage, current, power factor, pulse count, and measurement time. Subsequently, calculations were
carried out to determine the actual power (P1), the power measured by the kWh meter (P2), and the error value.The test results indicate that digital kWh meters exhibit higher
accuracy, with the majority of error values falling within the ±1% tolerance limit according to their accuracy class. In contrast, several analog kWh meters recorded error
values exceeding the tolerance limit, influenced by factors such as device age, mechanical quality, and calibration frequency. Additional factors affecting error values include
reading errors, unstable load conditions, and the quality of the measuring equipment.The study concludes that digital kWh meters are more consistent and reliable for use in
electrical energy measurement systems requiring high precision. These findings are expected to serve as a reference for PT PLN (Persero) and other relevant stakeholders in improving measurement quality through periodic calibration and the adoption of digital technology.