Limit switch

Description

A limit switch tells the controller that a moving axis has reached a defined point. On CNC routers, laser cutters and plasma tables, limit switches are used for homing, so the machine knows where zero is after power-up, and as end-of-travel protection that stops an axis before it hits its mechanical stop.

If the machine fails to home, runs past the end of an axis, or throws random limit alarms mid-job, suspect the switch or its cable. Mechanical switches wear at the lever and contacts, while proximity sensors can be upset by dust, metal chips or a bracket that has shifted out of range. Trigger the switch by hand and watch the controller's input status before replacing anything, and check the cable where it flexes inside the drag chain.

Limit switches come in mechanical, inductive and optical types with different wiring and supply voltages. Send a photo of your existing switch, its label and how it is mounted, and Top Laser's technicians will help you select an equivalent.