When used in conjunction with a properly designed safety system, SSP safety enabling switches provide the operator with a special control mode for tasks such as maintenance or debugging of hazardous equipment. These switches consist of a spring-return three-position (N.O.-N.C.-N.O.) grip button that must be maintained by the operator in the middle position for the machinery to continue operating.
In addition to the grip button, models are available that include a built-in E-stop button, LED indicators, additional pushbuttons for auxiliary functions or an activity sensor to detect when the switch is in its home position.