The PLR10-2D(PL10-2D) Run Off Switch detects conveyor belt misalignment; two microswitches can trigger an alarm or conveyor shutdown to protect the conveyor belt from damage when belt drift occurs.

When the belt runs off center, the roller arm will be deflected from its normal vertical position and at a preset angle activates the first microswitch which can output to an alarm. When the belt further displaces the roller arm by a preset angle, the second microswitch will be trigged to shut down the conveyor before damage can occur to the belt or plant.

The PLR10-2D(PL10-2D)  run off switch is usually installed in pairs at both sides of the belt and positioned at a distance between 0.3m and 2m from the head pulley or tail pulley. Typically, it can be fastened at the top or bottom of the conveyor stringers with the actuating arm located 25mm to 75mm away from the outside edge of the belt.

PL20 Safety Pull Switches

The Safety Pull Switch is mounted on or alongside the conveyor stringer, with one end of the pull wire fastened to a fixed post and the other end fixed on to the actuator arm. The pull wire is supported by standoff eyebolts every 3m. The distance between the switch and fixed post should not exceed 24m. The spacing between two switches should be no more than 48m.

When the actuator arm displaces (rotates) to the alarm position by force acting on the pull-wire, the microswitch is activated and interlocked until reset manually. The standard switch is protected to IP65, suitable for both indoor and outdoor installation. Where the optional nickel plated housing is specified, it can be used in acid, alkaline or salty environments. The nickel plated surface is well suited for highly corrosive application.

PL50 Belt Damage Detector

PL50 Damaged Belt Detector warns supervisory personnel of impending belt failures due to rips, punctures, splice failures, or sharp objects protruding through the belt fabric.

Belt Damage Detectors mount in pairs positioned on either side of the belt. The units are connected by two spans of aircraft cable. One end of the cable mounts permanently to a support bracket and the other connects to a spring-loaded ball located in the unit. The cables loop underneath the belt from each side crossing at the midpoint. A belt problem is detected when an object or a piece of damaged belt hangs below the belt's surface and sweeps away one or both cables. As the cable is detached, it pulls a spring-loaded ball out of a socket, causing two micro switches to sound an alarm or to shut down the conveyor.

PL40 Position Switches

Series PL position switches are utilized to monitor the position of heavy moving machinery such as a crane or skip. When the actuator roller is displaced, the switch is triggered by an arm; the microswitch inside then activates and signals a shut off to stop the moving machinery.