IEC 61557-12:2018 specifies requirements for power metering and monitoring devices (PMD) that measure and monitor the electrical quantities within electrical distribution systems, and optionally other external signals. 0 b:2024—Low-voltage switchgear and control gear assemblies – Part 3: Distribution boards intended to be operated by ordinary persons (DBO) specifies requirements for distribution boards intended to be operated by ordinary persons. Click on the chapter title/number in the navigation bar to move to the start page of the relevant chapter. 1 2 Con-. Finally, it summarizes the key differences between Class A and Class S power quality meters. Measurements of voltage, current and phase-angle as well as calculation of overall box power consumption are conducted in real-time. Main electronic board is. What is a distribution board and why it matters is a fundamental question for engineers and designers of modern electrical systems.