Fb30 pressure switches are used to regulate tank pressure between two preset values on small (up to 175psi) electrically driven air compressors. Equipped with an unloader valve, they could prevent compressors from starting under load, and an auto-off disconnect lever for manual cut off the compressor. Both one and four-ports manifold style are available which provides easy mounting of valves and gauges.. 1) operating pressure range: 5bar-12 bar; 2) differential pressure range: 2bar 3) 20a, 240vac, 50hz 0.3kg, cartons