Electric toe sensors are most commonly used on lift tables that are installed in a preformed recessed pit. In a recessed pit installation there is the potential for introducing a shear hazard as the platform lowers into the pit. Electric toe sensors are an interlocked 4 sided bar assembly that is suspended under the lower edge of the lift table platform. The suspended perimeter bar assembly interacts with 4 limit switches, one per corner. When the down button is activated the electrical signal to lower the platform travels from the controller through the 4 limit switches to the power unit lowering valve. During the lift table descent if any obstruction such as an operator’s foot, debris etc. contacts the suspended perimeter bar a minimum of 1 of the limit switches will immediately open circuit. This open circuit breaks the electric signal that travels from the controller to the power unit lowering valve; this broken signal stops the lift table descent immediately. When the operators foot is retracted or the debris removed the lift table now returns to normal operation.
Feb 28, 2020
