Allen-Bradley 440G-LZS21UPRH Guardmaster Safety Switch

 

 

Product Overview

The Allen-Bradley 440G-LZS21UPRH is a Guardmaster 440G-LZ RFID Guard Locking Safety Switch designed for machine guard doors and access protection systems. It combines non-contact RFID safety sensing with electromagnetic guard locking to prevent access to hazardous machinery until safe conditions are met.

Key Specifications

• Brand: Allen-Bradley (Rockwell Automation)
• Series: Guardmaster 440G-LZ
• Model: 440G-LZS21UPRH
• Product Type: RFID Guard Locking Safety Switch
• Operating Principle: Non-contact RFID coded actuator
• Locking Type: Power-to-Release
• Solenoid Voltage: 24 VDC
• Safety Outputs: 2 × PNP safety outputs
• Auxiliary Output: 1 × PNP lock status output
• Connection: 8-pin M12 quick-disconnect connector
• Holding Force (Fzh): Approximately 1300 N
• Protection Category: Suitable for applications up to SIL 3 / PLe / Category 4 when properly integrated into a safety system.

What It Does (Simple Explanation)

The switch monitors a machine guard door using RFID coding:

1. Door closes.
2. RFID actuator is detected.
3. Safety outputs turn ON.
4. Solenoid locks the guard door.
5. Machine is allowed to operate.
6. When the machine reaches a safe state, power is removed and the door can be opened.

This prevents operators from accessing dangerous moving parts while machinery is operating.

Key Features

• RFID coded non-contact sensing
• Integrated guard locking function
• Power-to-release operation
• High tamper resistance
• PNP solid-state outputs
• M12 quick-connect wiring
• Compact industrial design
• Suitable for high-performance safety systems

Advantages

• Improves machine safety and compliance
• Eliminates mechanical key wear common in traditional interlocks
• High resistance to vibration and contamination
• Fast installation using M12 connectors
• Supports modern safety PLC architectures
• Reliable monitoring of guard doors and gates

Applications

• Packaging machines
• Robotic cells
• CNC machines
• Automated production lines
• Material handling equipment
• Assembly stations
• Safety fencing and access gates
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