Metering Devices (APP) are a key component in the energy transaction sector at PT. PLN (Persero) because they affect the calculation of the company’s revenue. However, in the field, damage and tampering with APPs are frequently encountered, resulting in revenue losses for PLN. Damage to APPs generally occurs naturally due to the devices’ age. Meanwhile, tampering with APPs is usually caused by deliberate actions by customers who alter the wiring of the kWh meter to reduce the recorded energy consumption. Until now, PLN staff have struggled to verify the presence of damage or tampering in the AMUs due to time constraints and limited testing equipment, resulting in inspections being conducted only visually. This kWh meter error deviation measurement device will help PLN staff identify problematic AMUs more efficiently and easily. This device measures the power recorded by the APP via the LED impulse indicator parameter and compares it with the actual power consumed by the customer as measured by the PZEM 004T sensor module, thereby determining the percentage of the kWh meter’s error deviation. After obtaining the error deviation value, the device will send an SMS notification using an 800L SIM card to staff at the office; thus, if an error deviation value exceeding the tolerance limit is found, it will be used for enforcement purposes as well as customer analysis and evaluation (ANEV). The results from this device demonstrate good accuracy because, when testing different loads on the same APP, the deviation values do not fluctuate. in the tests conducted, the average deviation was 1.89% under normal conditions and -23.94% under conditions where a deviation was present. Furthermore, this device has an average error difference of only 0.59% when measurements are taken using the device compared to manual calculations of the error deviation. This device can help improve inspection efficiency.