Allen-Bradley 440T-AKEYE10AH Trapped Key Interlock

Allen-Bradley 440T-AKEYE10AH is a code Ah trapped-key interlock key designed for use with Rockwell Automation’s Guardmaster 440T trapped-key interlock system. This standard key is intended to be paired with 440T trapped-key interlock switches to control access to guarded equipment, ensuring the interlock sequence cannot progress unless the correct key remains in the intended position. The Ah designation identifies a specific key variant within the 440T family, and the catalog number 440T-AKEYE10AH confirms its exact compatibility with 440T interlock configurations. In practice, trapped-key interlocks coordinate doors, guards, and control circuits so that a hazard is isolated and maintenance can occur only when the key is carried to a corresponding control point, providing a physical layer of safety. Rockwell's 440T series is documented as a ProSafe/Guardmaster trapped-key interlock solution, and the Ah key is one of several codes used to differentiate concurrent interlock keys in multi-step safety workflows.