IEC 62423 specifies requirements and tests for Type F and Type B Residual Current Devices (RCDs), in addition to the existing standards IEC 61008-1 and IEC 61009-1. This standard is intended for use alongside these standards and outlines specific tests and requirements for Type F RCDs, which are designed for installations using frequency inverters, providing protection against alternating sinusoidal residual currents, pulsating direct currents, and composite residual currents. Type B RCDs offer protection against alternating currents up to 1,000 Hz, pulsating direct currents, and smooth direct currents. This second edition replaces the first edition from 2007, introducing new requirements for Type F RCDs, two-pole Type B RCDs, and additional criteria for Type B RCDs to ensure comprehensive protection.