Prepaid electricity meters (also known as quantitative energy meters or IC card electricity meters) are intelligent metering devices based on the "pay-before-use" model. Compliant with the GB/T18460.3-2001 standard, these devices utilize microelectronics technology, RF cards, and encryption algorithms to facilitate data exchange, offering features such as automatic metering, purchase control, low-balance alerts, power-off protection, and anti-theft capabilities. Internally, they are equipped with a microprocessor, a metering module, and an IC card interface; a dedicated metering chip converts voltage and current signals into electrical energy values, while the system manages user account balances in real-time. These meters support remote communication, multi-tariff configurations, and time-of-use (TOU) pricing, making them suitable for both single-phase and three-phase power consumption scenarios.
The technological evolution of these devices has progressed through three distinct stages: storage-chip-based "electronic key" IC cards (pre-1995), logic-encrypted cards (1995–1999), and financial-grade CPU cards (post-1998), with the latter integrating encryption algorithms and operating systems to enhance security. Users can top up their accounts via IC cards (using either code-based or card-writing methods) or through online payment channels. To ensure metering accuracy, the vertical installation deviation of the meter must not exceed 2 degrees. The devices feature power-limit controls, abnormal usage monitoring, and automatic power-cutoff functions, and can be integrated with remote monitoring systems to optimize electricity billing management efficiency.
Prepaid electricity meters-alternatively termed quantitative energy meters or IC card electricity meters-go beyond the standard metering functions of conventional meters by implementing a unique "pay-before-use" mechanism: users must purchase electricity credits in advance before they can consume power. If a user exhausts their purchased credits and fails to top up their account, the device automatically cuts off the power supply. These meters are designed to measure single-phase AC active energy at a rated frequency of 50 Hz, thereby enabling effective "pay-before-use" management. They employ advanced microelectronics technology for data acquisition, processing, and storage, utilizing RF cards as the medium for data transfer. Furthermore, advanced remote prepaid meters support a variety of communication protocols-including RS-485 wired connections, 4G wireless networks, NB-IoT technology, and Power Line Carrier (PLC) communication-to facilitate the remote transmission and management of data. To ensure the security of data and financial transactions, prepaid electricity meters commonly incorporate robust security measures such as CPU cards, ESAM (Embedded Secure Access Modules), and encryption algorithms like 3DES. Its performance specifications comply with the requirements of standards such as GB/T17215.321-2008, GB/T18460-2001, and DL/T645.