4HS79

Snap Action, Limit Switches: 4HS79 Application Field and Working Principle

The 4HS79 is a snap action, limit switch that is designed for the purpose of electrical position and presence sensing for applications in residential and commercial settings. The 4HS79 is intended for use when fail-safe circuit logic is desired, such as in safety systems. This switch can be used for applications such as door and window position detection, HVAC control, and as a safety interlock switch.

The 4HS79 is a rugged device that is designed for operation in a variety of harsh environment conditions. It is UL Listed, cUL listed and CE approved. The switch has a wide operating temperature range of -40°C to +90°C, and is rated IP67 for operation in environments that are subject to dusty or damp conditions.

The 4HS79 has three distinct operating modes: momentary, maintained, and double-break. Momentary operation is when the switch is momentarily pushed to activate. Maintained operation is when the switch is pushed and then held in the same position until it is manually released. Double-break operation is when the switch is operated in two distinct ways; when the switch is pushed one way, it activates and when the switch is pushed in the opposite direction it is reset. All three of these operations can be useful depending on the application.

The 4HS79 has several features that make it an ideal choice for safety-related applications. It is available with one or two actuators, allowing for dual-stage monitoring. The switch can be set for a wide range of operating forces, from 0.6 N to 7 N, and it features an adjustable pressure force break, allowing it to be set to a specific travel distance. Additionally, the 4HS79 features gold-plated contacts to provide the highest level of electrical performance.

The working principle of the 4HS79 is founded on the concept of a mechanical switch with a set of two contacts. The two contacts are formed by a movable plunger that is fixed to a pivot arm. When the plunger is depressed, it pivots the arm and closes the electrical contacts, completing the circuit, and when the plunger is released the contacts are opened, breaking the circuit. The plunger is held in position by a spring-loaded mechanism that snaps the plunger back into position when the force is released.

The 4HS79 is a dependable and versatile switch for applications in residential and commercial settings where fail-safe logic is necessary. It can be used for a variety of applications, from position sensing and presence detection to HVAC control, and it features adjustable pressure force, gold-plated contacts, and robust construction for use in a variety of environments. The 4HS79 is a great choice for applications where safety is a priority.