Schneider Electric RM22TG20 Modular 3-Phase Power Supply

The RM22TG20 Harmony modular 3-phase supply control relay from Schneider Electric monitors three-phase power networks and provides automatic shutdown and fault indication, rated for up to 8 A with two changeover contacts across 183–528 VAC, and it serves as a direct replacement for the RM4TG20 within the Harmony line. Its compact 0.89 in (22.5 mm) width supports a tidy, panel-friendly installation and aligns with the streamlined footprint of other Harmony modular relays, helping minimize panel depth and allow easy stacking or side-by-side installation. The device continuously checks for critical power-supply anomalies, including absence of neutral, phase asymmetry, phase failure (including two or more phase cuts), phase sequence, and overvoltage/undervoltage or over/under frequency between neutral and phases, delivering precise fault signals for rapid diagnostics. This makes it well suited for industrial automation, control panels, and machine-builders that require reliable phase monitoring and a clear fault output to enable quick fault isolation and safe shutdown in 3-phase systems.