Siemens 171C-10600-0.8-1.2 6W BALL VALVE 1/2", A=0.8CV, B=1.2CV, 58PSI CLOSE-OFF, FEMALE NPT, 0-10 V NSRSiemens 171C 10600 0. 8 1. 2 This 1 2 inch 599 Series 6 way ball valve with a 0 10 Vdc control fail in place actuator assembly is used to control hot or chilled water and up to 50% Glycol solution in chilled heated beams and other four pipe systems using a single valve and actuator. 58 psi close off with 0% leakage. Source A = 0. 8 Cv and Source B = 1. 2 Cv, linear flow characteristic and chrome plated brass ball and stainless steel stem and Cv