Auxiliary Switch - 16 Amp MOC and TOC

The auxiliary switch is a compact rotary contact block used for position indication, interlock, and signaling in industrial switchgear, motor control centers, circuit breakers, and control panels. Configured as either an MOC (Mechanism-Operated Contact) or TOC (Truck-Operated Contact) unit, the switch reports the state of a primary device — such as a breaker's open/closed position or a truck's racked/withdrawn status — to remote monitoring, indication, or interlock circuits. UL-rated for 16 amperes at 250 VAC and 250 VDC, and 7.5 amperes at 600 VAC, this switch handles typical control-circuit loads directly without external contactors.

Each switch supports up to 20 poles in a closed-construction stack, with 90 degree indexing between positions. Contact behavior is break-before-make, which prevents inadvertent short-circuits during transitions — critical for interlock applications where two states must never overlap. Contact resistance is specified at 10 milliohms maximum (4 milliohms average), and initial insulation resistance exceeds 1,000 megohms. Dielectric withstanding voltage is 2,500 VRMS initial, providing generous margin above the operating voltage. Terminals are available in screw or quick-connect styles to match panel wiring practice.

Configurations are specified by the number of A contacts (closed when the main device is in the reference position) and B contacts (open in the reference position), the shaft extension dimension for coupling to the driving mechanism, and the terminal style. A range of lever couplings is available for connection to specific breaker mechanisms, drawout truck operators, and disconnect handles. Typical applications include medium-voltage switchgear, low-voltage motor control centers, air circuit breakers, transformer tap changers, and custom control panels where reliable position sensing and interlock signaling are required.