The APM5 series network power meter (hereinafter referred to as the meter) is designed according to IEC international standards and has functions such as full power measurement, power statistics, power quality analysis (including harmonics, interharmonics, flicker), fault recording (including voltage rise and fall interruption, impulse current recording, etc.), event recording, and network communication. It is mainly used for comprehensive monitoring of power supply quality in the power grid. This series of instruments is equipped with feature rich DI/DO modules, AO modules, wireless communication modules, and leakage temperature measurement modules, which can flexibly achieve full power measurement and switch status monitoring of electrical circuits.