• Schrader Duncan Limited

Smart Positioner

Pneumatic cylinders suffer from a limitation that they can be stopped only at extreme positions, either at the front end or at the rear end. Many applications call for stopping of pneumatic cylinders at precisely selected intermediate positions for controlling the degree of opening of dampers, knife gate valves or butterfly valves, which in turn control various process parameters. This can be achieved by using positioners in conjunction with pneumatic cylinders. Smart positioner, Model SDSP 2300R, controls stroke of the cylinder or actuator in proportion to the input signal between 4-20 mA. Besides, an efficient built in microprocessor performs functions like auto calibration, PID control, alarm and hart protocol etc. Specifications: item – single acting – double acting; input signal – DC 4-20 mA; supply pressure – 1.4~7 kgf/cm² (20~100 PSI); stroke (linear/rotary) – 50 to 1000 mm/0~90º; impedance – max 460 Ohm/20 mA DC; air connection – PT (NPT) ¼”; linearity – ±0.5% FS; and material – die cast aluminium.