本规范涵盖了额定电流为0.050安培至20.0安培（包括0.050安培）、高达240伏、60赫兹（Hz）和400赫兹交流电（ac）以及50伏直流电（dc）的单极和多极、无跳闸、密封、低功率磁性断路器的要求和试验程序（见6.1和6.7）。这些断路器还可能包括辅助触点（见6.6.1）和用于监测电路的端子。设计师应注意，这些断路器的某些零部件可能含有纯锡饰面（见6.5）。

This specification covers the requirements and test procedures for single and multipole, trip-free, sealed, low-power, magnetic circuit breakers with current ratings of 0.050 amperes to 20.0 amperes inclusive, up to and including 240 volts, 60 hertz (Hz) and 400 Hz alternating current (ac), and 50 volts direct current (dc) (see 6.1 and 6.7). These circuit breakers may also include auxiliary contacts (see 6.6.1) and terminals for monitoring circuits. Designers are CAUTIONED that these circuit breakers may contain a pure tin finish on some of the component parts (see 6.5).