Allen-Bradley 440T Prosafe Trapped Key Switch with Electronic Timed-delay

The Allen-Bradley 440T Electronic Timed-delay Unit Trapped Key Interlock Switches are ideal for applications requiring an elapsed time to occur before access to a hazardous area. A combination of Guardmaster® SI and EMD safety relays execute the timing sequence by turning a non-removable key, when the EMD times out an internal solenoid is energised allowing the removal of the trapped keys.