Schneider Electric R-12 Electrical Interlock Class 9999

Schneider Electric's Square D R-12 Electrical Interlock, Class 9999, is a complete interlock kit designed to mount on Square D disconnect mechanisms to prevent simultaneous energization of the main and control circuits. As part of the Class 9999 interlock family, these interlocks are used with disconnect switches and circuit breakers to ensure the control power is isolated when the main disconnect is OFF. Complete Class 9999 interlock kits are rated for NEMA Type 1, 3R, and 12 enclosures, making them suitable for a range of industrial environments. Within the Type R flange-mounted family, Class 9999 interlocks are commonly offered in SPDT (R26) and DPDT (R27) configurations, enabling single-pole or double-pole control-circuit interlocks depending on the application. The R-12 designation identifies a specific Square D interlock variant within the Class 9999 catalog.