ABB mkey8z 24vdc Interlock Switch, 2NC+2NC

Why Choose the ABB MKey8Z 2TLA050011R0122 Safety Interlock Switch?

The ABB MKey8Z 2TLA050011R0122 is a heavy-duty solenoid safety interlock switch designed for monitoring and locking movable machine guards, doors and access hatches. As part of the ABB Jokab Safety MKey series, it combines mechanical guard position monitoring with a spring-operated locking mechanism to help prevent access to hazardous machinery until safe unlocking conditions have been established.

The MKey8Z uses a power-to-unlock operating principle. The guard remains mechanically locked by spring force and a 24 V DC supply is applied to the solenoid when unlocking is required. This fail-to-safe locking arrangement makes the switch particularly suitable for machinery where access must remain prevented following a loss of electrical power.

Designed for demanding industrial environments, the MKey8Z features a stainless steel housing and locking head, IP67 and IP69K protection and a substantial 2000 N holding force. Its dual safety contact sets monitor both the guard actuator and locking mechanism, while three M20 conduit entries and the supplied standard actuator key support straightforward integration into industrial machine safety systems.

Key Advantages

• Heavy-duty solenoid safety interlock switch with guard locking.
• Power-to-unlock operation keeps the guard spring locked until the solenoid is energised.
• 2000 N holding force provides robust mechanical guard locking.
• Durable stainless steel housing and locking head for demanding environments.
• IP67 and IP69K protection provides excellent resistance to dust, water and high-pressure cleaning.
• Designed for safety systems achieving up to PL e / Category 4 and SIL 3, depending on the overall system architecture.

Key Features

• ABB Jokab Safety MKey8Z series.
• 24 V DC solenoid with power-to-unlock operation.
• 2NC safety contacts for lock monitoring + 2NC safety contacts for actuator monitoring.
• Additional auxiliary indication contacts associated with the lock and actuator states.
• 2000 N maximum holding force.
• Three M20 conduit entries for cable installation.
• IP67 / IP69K stainless steel construction.
• Supplied with a standard actuator key.

Reliable Guard Locking for Hazardous Machinery

Solenoid safety interlock switches combine guard position monitoring with mechanical locking to help prevent personnel from opening a protective guard while hazardous machine movement or processes remain active. The ABB MKey8Z is mounted on the fixed machine structure while its separate actuator key is fitted to the movable guard, allowing the safety system to monitor both guard position and locking status.

The MKey8Z uses a spring-to-lock, power-to-unlock mechanism. When the actuator is inserted and the locking mechanism engages, the guard can withstand a holding force of up to 2000 N. Applying the required 24 V DC supply energises the solenoid to permit unlocking, making this arrangement particularly appropriate where a guard must remain locked until a controlled safety signal allows access.

Typical Applications

• Industrial machine guard doors and access gates.
• Machinery with hazardous run-down or stopping times.
• Robot cell and automated equipment enclosures.
• Packaging and production machinery.
• Conveyor and material handling safety systems.
• Washdown and demanding industrial environments requiring stainless steel construction.