Process Interlocking Actuator Locking System (ALS) Electrical actuator NETHERLOCKS offers the ALS, an actuator locking device to suit all sizes and types of actuators – linear and rotating, electric and Pneumatic / hydraulic. To lock an actuator the philosophy is always the same: lock the power supply and guarantee the position. In case of an actuator you need to control the power source. This could be air, oil or electric power. A combination of NETHERLOCKS products can be used to create a locking procedure to lock a MOV e.g. a switch lock, a manual override lock, an air supply lock and a position checker. The below sample shows you how to switch-over an electrical actuator from open to close. Sequence: 1. Valve is open, power is OFF, open key is released 2. Insert open key (green) into A.P.C. 3. Releasing a switch key (yellow) 4. Insert switch key into Switch Lock to unlock the power 5. Activate the power, the switch key is no trapped 6. Operate actuator to CLOSE, 7. Deactivate power, the switch key is no released 8. Insert switch key into A.P.C. 9. Release close key (red), only possible in case the actuator is FULLY close and switch key is present.