AZM200 Solenoid Interlocking Device

Overview

The Schmersal AZM200 is a Type 2 interlocking device with solenoid guard locking, designed for safety gates and access doors on machinery where hazardous movement must be prevented while a guard is open, and — crucially — where the guard must remain locked until the hazard has safely stopped (e.g., robot reaching a safe position, inertial flywheel coming to standstill). The solenoid bolt engages automatically when the actuator enters the head and the 24 V DC coil is energised. Spring-to-lock design ensures the gate remains locked if power is removed — a fail-safe condition that prevents accidental unlock during power interruptions.

The 2000 N rated holding force of the AZM200 (measured at the actuator engagement point) significantly exceeds the force a standing person can typically apply to a door (approximately 200–400 N for pushing, up to 1000 N for a full bodyweight lean), providing confidence that the guard cannot be forced open while the bolt is engaged. For comparison, budget interlocks rated at 1000 N can be overcome by determined individuals — a critical safety concern for robot cell installations where personnel could face severe injury if they entered while the robot was in automatic mode.

The two independent NC contacts with positive opening action ensure that weld-shut or stuck contacts are detected by the safety relay — a requirement of Cat. 4 / PLe per ISO 13849-1. The separate NO monitoring contact allows the safety controller to confirm contact state diversity. Schmersal's coded RFID actuator option (AZM200Z-coded) prevents common-cause defeat by a simple metal object inserted in place of the actuator — the RFID transponder must match the switch's stored code for the "door closed" output to activate.

Key Features

• 2000 N Rated Holding Force — Mechanical Defeat Resistant — The solenoid bolt is rated to 2000 N static holding force per ISO 14119, tested perpendicular to the guard plane. This comfortably exceeds human push forces and meets the "high holding force" category requirement for applications where injury severity is high (e.g., robot cells, hydraulic presses, high-inertia centrifuges).
• Coded RFID Actuator — Anti-Manipulation — The AZM200Z-coded variant stores a unique 128-bit RFID code in the switch head. Only the paired coded actuator mounted to the door produces a valid "door-closed and locked" signal — a plastic strip, metal ruler, or generic actuator cannot activate the NC safety contacts. This meets the Level 3 coding requirement of ISO 14119 for high-risk applications.
• 4-Pole Positive-Opening Contacts — Cat. 4 / PLe — Two independent NC safety contacts with direct positive-opening action (per IEC 60947-5-1 Annex K) mean any weld-shut or mechanically stuck contact causes contact separation — the redundant contact detects the fault. The separate NO monitoring contact provides state cross-check for the safety relay or safety PLC's diagnostic channel, achieving Cat. 4 CCF requirements without additional cross-monitoring wiring.
• IP67 — Wash-Down Resistant — Sealed to IP67 (1 m water immersion, 30 minutes), the AZM200 withstands daily high-pressure wash-down cycles in food & beverage and pharmaceutical applications. Stainless steel actuator versions are available for corrosive environments. The M12 8-pin connector option eliminates cable-entry IP vulnerabilities versus traditional cable glands.

Technical Specifications

Application Areas

• Robot cell access gates requiring guard locking until robot reaches safe position
• Hydraulic press and stamping machine interlocking
• High-inertia machine guarding (flywheel run-down time > 10 s)
• Pharmaceutical isolator and clean-room access control
• Food & beverage packaging machine guards (wash-down IP67)
• Chemical processing vessel access interlocking