Series ER Roller-operated valves, 3/2- and 5/2-way, M5 (10/32 UNF) and G1/8 • 80 to 320 Nl/min (0.081 - 0.325 Cv) ER-18-310, ER-18-310-Q Design, function and technical data Types ER-25-310 and ER-28-310: Port 1 must be used as the pressure inlet. Types ER-18-310 and ER-18-510: All ports are interchangeable. Valves ER-18-310 and ER-18-510 are available for use with vacuum (-0.95 ... 12 bar/-14 ... 175 psi). Order number changes to ER-18-310-Q and ER-18-510-Q. 1 = pressure inlet (7) = pre-stroke, valve is not actuated