Allen-Bradley 440G-TZS21UTLH Safety Interlock Switch

 

Product Overview

The Allen-Bradley 440G-TZS21UTLH is a Guardmaster TLS-Z GD2 safety interlock switch (guard locking type) used for machine safety door control.

It is designed to ensure that protective doors or guards remain locked until dangerous machine motion has stopped.

Key Specifications (verified)

• Brand: Allen-Bradley (Rockwell Automation)
• Series: Guardmaster TLS-Z GD2
• Model: 440G-TZS21UTLH
• Type: Guard locking safety interlock switch
• Locking principle: Power-to-Lock (PTL)
• Safety outputs: 2 × PNP safety outputs + auxiliary door status output
• Actuator: coded flexible tongue actuator
• Connector: 8-pin M12 industrial connector
• Solenoid voltage: 24V AC/DC
• Holding force: ~2000 N (high-force door locking)
• Protection rating: IP66 / IP69K (washdown industrial use)
• Safety standard: ISO 14119, PL e (Cat.4 safety systems)

What It Does (Simple Explanation)

This device is installed on machine safety doors:

1. Door closes → actuator enters switch
2. Machine locks door using solenoid
3. Safety PLC checks status
4. Machine runs only when:
   • door is closed
   • lock is engaged
5. When machine stops safely → door can be unlocked

Key Features

• Power-to-Lock safety design (fails safe if power is lost)
• Strong 2000N holding force (resists forced opening)
• Dual-channel safety outputs (redundant safety signal)
• RFID/unique coded actuator system (anti-tamper)
• IP66/IP69K industrial protection (harsh environments)
• M12 quick connector for easy installation

Advantages

• High safety level (Category 4 / PL e systems)
• Prevents accidental machine access
• Strong mechanical locking force
• Suitable for washdown and harsh industrial environments
• Easy integration into modern safety PLC systems

Applications

• Robotics safety doors
• CNC machine guards
• Packaging machinery
• Automotive production lines
• Industrial automation cells
• High-risk rotating machinery enclosures