Guard locking switch for machine safety circuits
The Omron D4SL-N3PDA-D is a guard locking switch with a mechanical lock and solenoid release, designed to implement safe monitoring functions on access guards and safety gates. Its 1300 N key holding force means it physically resists forced opening of the guard door up to that pull-off load — a spec that matters when you're securing a heavy interlock on a press or robot cell where an operator might lean against the door. The solenoid operates on 24 VDC; the orange indicator lights at the same voltage, giving a clear visual that the solenoid is energized and the lock is engaged.
Contact configuration and wiring
Six contacts total, arranged as 2 NC / 1 NO + 3 NC. That's two normally-closed safety channels for the guard position, plus a three-contact NC block and one NO auxiliary. The NC contacts are the ones you wire into the safety relay or safety PLC input circuit — they drop out when the guard opens. The NO contact can signal a PLC that the door is locked, or drive a status lamp. Connection is via terminal block, so no special tooling needed at the panel. Conduit entry is 1/2-14NPT; the box includes an M20-to-1/2-14NPT conversion adapter, which saves a step if your local code calls for metric fittings.