Rugged enough for mining operations, these limit switches require a high actuation force, like heavy rocks moving on a conveyor. They open and close a circuit as quickly as a snap-acting switch but have a larger actuator for larger objects. The roller on the end of the lever arm reduces friction to prevent wear and tear on the switch. Rated NEMA 4 and 13 as well as IP67, these switches are protected from dirt, oil spraying, and temporary submersion.

To determine if you need a right or left actuation direction, stand facing where you'll put the switch. If objects will be passing to the right, you'll need a right actuation direction. If they'll be passing to the left, you'll need a left actuation direction.

Also known as interlock switches, these ensure the safety of personnel by automatically shutting off power to machinery when an access door opens. Mount the switch to the door frame and mount a key to the door so that the key is inserted into the switch when the door is closed. When the door opens, the key is removed from the switch and the machine shuts down. They’re often used with machine guards for large robots.

All switches require an actuator key, but not all include one—check whether you need to pick out a separate actuator key. For some switch styles, you can also select the mounting orientation of the key. Flexible keys pivot at least 15°, making them easier to align with switches during installation.

Style A-G switches have positive-force, normally closed contacts that will open a circuit when the switch is actuated even if a spring fails or the contacts stick.

IP67 rated switches protect against temporary submersion.