Siemens 6DR5110-0NN00-0AA3 Intelligent electropneumatic positioner SIPART PS2 for linear and part-turn pneumatic actuators; 2-wire; 4…20mA with HART interface; single-acting; Polycarbonate enclosure Standard Without explosion protection. Connection thread el.: 1/2″ NPT / pneumatic: 1/4″ NPT Without limit monitor. Without option module. Short instructions English/German/Chinese. Standard / Fail-safe: Depressurization of the actuator in the event of a power failure.