Telemecanique Sensors XCS LF Solenoid Interlock Switch. From Telemecanique Sensors this is the XCS LF series of safety solenoid interlock switches providing you with the solution when running machinery and a guard or door stays closed. Interlock switches protect machine operators by stopping the equipment when the door or guard opens by withdrawing the actuator attached from the switch head. The XCSLF solenoid interlock switch is ideal for use with heavy duty industrial machines with a low rundown time. The Telemecanique Sensors XCS-LF series solenoid interlock switch has a power supply voltage rating of 24VAC/DC. It has 2 NC/1 NO safety slow break contacts. The switch is made of a metal housing material and is a power to unlock type. Features and Benefits.