Series 4000 pressure switches convert a pressure signal to an electrical output. In response to a change in pressure, movement of an elastomeric diaphragm opens or closes an electrical circuit based on a predetermined pressure set point. The Series 4000 features cost effective, snap-acting electrical switches and field adjustable set points with a visual scale for easy set point selection. Pressure ranges as low as 2" (500 Pa) Water Column (W.C.)* up to 11 PSI (76 kPa) are available. Series 4000 switches assure control stability through wide and variable temperature and humidity conditions and assure uninterrupted service under extreme shock and vibration. As with all Tecmark® products, series 4000 switches provide superior performance and 100,000 cycle life under full mechanical, electrical and thermal loads.