440N-Z21W1PH | Allen-Bradley Sipha Non-Contact Magnetic Safety Switch, 25 mm

The 440N-Z21W1PH is a non-contact, magnetically coded safety switch designed to secure machine guards or protective doors. It is part of Allen-Bradley’s MC2 series and ensures that machinery stops or remains inoperative unless guards are closed. This type of switch is ideal for safety-critical environments, offering category 4 protection under EN ISO 13849-1. The magnetic coding adds resistance to tampering and accidental activation. Its solid-state outputs make it suitable for integration with modern safety relays and PLCs. It is widely used in packaging, food processing, and automated assembly systems.

The switch operates using a magnetically coded actuator, which must be aligned within a 25 mm range to enable output signals. When the actuator is removed (e.g., guard opened), the switch deactivates its safety outputs. The coded nature of the magnetic signal prevents defeat using standard magnets. It uses a solid-state relay output to send signals without mechanical wear. The tamper-resistant design enhances machine safety integrity. This non-contact operation ensures zero contact bounce and longer operational life.

The 440N-Z21W1PH has a maximum sensing distance of 25 mm, allowing for slight misalignment or door play. This makes it easier to install on hinged or sliding doors without precise positioning. The switch operates reliably when the actuator is within range and properly aligned. The wide operating distance contributes to installation tolerance and user flexibility. This ensures stable switching even with mechanical wear over time. Magnetic coding preserves the integrity of activation logic.

Yes, the 440N-Z21W1PH comes complete with a standard magnetic actuator. This paired component is coded to match the sensor and must be properly aligned for operation. The actuator is non-powered and passive, making it easy to install. It can be mounted to the moving part of a door or guard. The included set guarantees reliable switching out-of-the-box. Replacement actuators must match the sensor's coded specification.

Yes, the 440N-Z21W1PH is currently active and available through Rockwell Automation and authorized distributors. It remains part of the standard MC2 series of non-contact safety switches. There are no published lifecycle discontinuation notices as of now. This model is widely adopted in global safety applications. Availability of spare parts and documentation is guaranteed through standard Rockwell channels. Always confirm using the Rockwell Lifecycle tool before new deployments.