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Trapped Key Interlock Switches

Our Trapped Key Interlock Switches can be configured to ensure that a predetermined sequence of events takes place or that hazards have been reduced before operators become exposed to them.

440T Access & Chains

Bulletin 440T Access & Chains Trapped Key Interlock Switches

Our Access/Chains Trapped Key Interlock Switches allow access to hazardous areas only when an appropriate key is inserted into the interlock. These stainless steel access interlocks provide a rugged, industrial grade method of helping prevent access through gates. They are actuated by either a lever or a rod that is connected to chain.

440T Access & Chains


440T Bolt

Bulletin 440T Trapped Key Bolt Interlock Switches

Our Bolt Trapped Key Interlock Switches allow access to hazardous areas only when an appropriate key is inserted into the interlock. These stainless steel bolt interlocks provide a rugged, industrial grade method of helping prevent access through gates. With these bolt interlocks, there is no need to run power wires to the gate. These bolt interlocks are available in mechanical, electrical and solenoid switch types.

440T Bolt


440T Timed-Delay Unit

Bulletin 440T Trapped Key Switch with Electronic Timed-delay

Our Electronic Timed-delay Unit Trapped Key Interlock Switches are used in applications that require an elapsed time to occur before allowing access to a hazardous area. This interlock switch uses a CU1 control unit timer to execute the timing sequence. Turning a non-removable key initiates the timer. When the CU1 times out, its output energizes an internal solenoid, which then allows the removal of either one or two trapped keys.

440T Timed-Delay Unit


440T Exchange Unit

Bulletin 440T Trapped Key Interlock Exchange Unit Switch

Our Exchange Units for Trapped Key Interlock Switches are used in an interlocking sequence to link together other devices in the ProSafe® range. These units cater to more complex operating sequences.

440T Exchange Unit


440T Miniature Valve

Bulletin 440T Miniature Valve Trapped Key Interlock Switches

Our Miniature Valve Trapped Key Interlock Switches are an ideal solution for applications where space is at a premium. Features include locked open or locked closed options.

440T Miniature Valve


440T Slamlock

Bulletin 440T ProSafe Slamlock Trapped Key Interlock Switches

Slamlock™ Trapped Key Interlock Switches combine the features of trapped keys with tongue actuated interlocks. When the actuator is inserted into the interlock (guard closed), the trapped key can be rotated and removed. With the key free, the actuator cannot be removed. This locks the guard door. The trapped key must be re-inserted and rotated 90° to unlock the guard door.  Slamlock Interlock Switches are available in mechanical, electrical, and solenoid versions.

440T Slamlock


440T Rotary

Bulletin 440T Rotary Trapped Key Interlock Switches

Our Rotary Trapped Key Interlock Switches are used for electrical isolation of machinery to improve safe access and also as teach boxes in robot cells. Once the power has been turned off, the key can be withdrawn and used in the next sequence of operation such as unlocking an access hatch or allowing valves to be operated. The rotary switch can be mounted in a panel or purchased in an enclosure.

440T Rotary


440T Solenoid Release Unit

Bulletin 440T Trapped Key Solenoid Release Unit

Our Trapped Key Solenoid Release Unit electrically isolates machinery to improve access safety. The unit consists of a rotary power switch and a solenoid. The trapped key can be removed once an external signal is given to its internal solenoid locking mechanism. An indicator light on the solenoid release unit shows when the trapped key can be removed—that is, when power is applied to the solenoid. The solenoid signal only needs to be present when key removal is necessary.

440T Solenoid Release Unit


440T Stopped Motion Unit

Bulletin 440T Trapped Key Stopped Motion Unit

Our ProSafe® Stopped Motion Unit (SMU) is used in applications that require the detection of stopped motion of mechanical parts of a machine. The SMU uses inductive proximity sensors to detect motion and the CU2 control unit to monitor the sensors.

440T Stopped Motion Unit


440T Switchgear Adaptors

Bulletin 440T Trapped Key Switchgear Adaptors

Our Trapped Key Switchgear Adaptor is used to interlock preparatory switch gear applications or other host equipment such as spool valves. Power is isolated and locked off when the key is rotated and removed. The key can then be used in the next sequence of operation.

440T Switchgear Adaptors