Pressure switch, Pressure Range: The 3/6 model has a typical adjustment range from 3 to 10 bar (or 43 to 145 psi). The factory pressure is often set between 6 and 8 bar., Electrical Configuration: The pressure switch is designed for operation with single-phase (1-phase) 230 V AC or sometimes three-phase motors., Air Inlet: Usually a threaded connection (typically female BSP or NPT).1/4 inch