SIPART PS2 Smart, electropneumatic positioner, FOUNDATION Fieldbus, Ex/nEx, double-acting, polycarbonate enclosure, for pneumatic linear and part-turn actuators. Standard Without explosion protection. Connection thread el.: 1/2" NPT / pneu.: 1/4" NPT Without limit monitor. Without option module. . Brief instructions English / German / Chinese. Standard / Fail-Safe - Depressurizing the actuator in case of failure of electrical auxiliary power (single acting only). Without Manometer block / Venting gauge block / Booster.