This work describes the development of a non-invasive and low-cost process that allows for the improvement of the energy theft inspection routine, increasing the field inspection team productivity and reducing the customer's embarrassment in cases where no irregularity is found. This new process is based on the development of an electronic Ah meter device that can be installed on the customer's pole input connections to the power lines. Using the recorded Ah value in the device, it is possible to estimate, within a margin of error, the energy consumption of the customer during a small period, typically one week. This energy value is compared to the customer's regular energy meter reading for the same period. A comprehensive statistical study performed with a database of more than 80000 customers in distribution area of the utility company AES Eletropaulo in São Paulo, Brazil concludes that the comparison between these readings can clearly indicate when tampered or defective meters are found.728089Depuru, S., Wang, L., Devabhaktuni, V., Gudi, N., Measures and setbacks for controlling electricity theft (2010) IEEE North American Power Symposium-NAPS(2009) Bureau for Economic Growth, Agriculture and Trade, , U. S. Agency for International Development Washington, D. C., Transforming Electricity Consumers into Customers: Case Study of a Slum Electrification and Loss Reduction Project in São Paulo, BrazilOnat, N., Transmission and distribution losses of Turkey's power system (2010) Proceedings of the 4th WSEAS Conference on Advances in Energy Planning, Environmental Education and Renewable Energy SourcesSmith, T., Electricity theft comparative analysis (2003) Energy Policy, 32, pp. 2067-2076Fitch, M., Graham, C., (2000) Electricity and Gas Theft, , Centre for Utility Consumer Law, University of Leicester, UKKenny, C., Soreide, T., (2008) Grand Corruption in Utilities, , World Bank Policy Research Working Paper 4805Sarpa, C., (2008) Electricity Theft and Non-payment: Impact on the sa Generation Capacity Crisis, , Yelland, Conference PaperOnat, N., Techno-economic analysis of illegal electricity usage in Turkey and policy proposals (2010) WSEAS Transactions on Power Systems, 3, pp. 213-222Stajic, Z., Janjic, A., Simendic, Z., Power quality and electrical energy losses as a key drivers for smart grid platform development (2011) Proceedings of the 15th WSEAS International Conference on Systems - Recent Researches in System Science, pp. 417-422Kadurek, P., Blom, J., Cobben, J., Kling, W., Theft detection and smart metering practices and expectations in the Netherlands (2010) Innovative Smart Grid Technologies Conference Europe (ISGT Europe) IEEE PESOliveira-De Jesus, P., Alvarez, M., De Ponce Leao, M., Yusta, J., A novel approach to evaluate incremental transmission losses (2009) WSEAS Transactions on Power Systems, 1, pp. 12-21Ghajar, R.F., Khalife, J., Cost/benefit analysis of an AMR system to reduce electricity theft and maximize revenues for Électricité du Liban (2003) Applied Energy, 76 (1-3), pp. 25-37. , DOI 10.1016/S0306-2619(03)00044-8Nagi, J., Mohammad, A., Yap, K., Tiong, S., Ahmed, S., Non-technical loss analysis for detection of electricity theft using support vector machines (2008) Proceedings of the 2nd IEEE International Conference on Power and Energy (PECon 08), pp. 907-912(2008) MSP430FE42x Mixed Signal Microcontroller Data-sheet, , Texas Instruments(2011) CC2550 Low-cost Low-power 2.4 GHz RF Transmitter Data-Sheet, , Texas InstrumentsMorais, F., (2011) Development of an Electronic Wireless RMS Current Meter for Applications in Detection of Electrical Energy Theft, , M. Sc. Thesis in Electrical Engineering, Faculty of Computer and Electrical Engineering, University of Campinas, BrazilPomilio, J., Deckmann, S., Characterization and compensation of harmonics and reactive power of residential and commercial loads (2007) IEEE Transactions on Power Delivery, 2