The Positioner SRD991 w/o communication by FOXBORO ECKARDT is a micro-processor controlled, electro-pneumatic positioner with an analog input signal of 4-20 mA. This positioner compliments the extensive product scope by FOXBORO ECKARDT.

The Digital Positioner possesses the same intelligence as the Intelligent Positioner SRD991 , however being different in one aspect - not requiring any communication. Therefore, the Digital Positioner is a budget-priced alternative to the positioner with communication. Conversion to the respective other electronics is easily feasible, because of the modular structure. It offers the functionality of the most modern positioners such as Autostart for determination of mechanical travel stops and control parameters as well as a dynamic optimization of the control behavior. This substantially reduces the expenditure for configuration and start-up of the device. The possibility is unique to suit the control parameters for P, I, as well as for T63 individually for both directions of movement to the respective process conditions.

Additionally, determined control parameters can be read and filed if necessary for both the Intelligent and the Digital Positioners. The attachment to linear as well as rotary actuators is feasible with only one device version in different mounting positions. Additonally, there are two binary inputs and outputs as well as an analog position feedback which may be optionally upgraded. These may be combined with an inductive limit switch in order to indicate an end position.

Due to the very low air consumption of the device and the resulting minimum overpressure to the atmosphere, the device is continuously rinsed with clean process air. This aspect has been profitable at those locations where aggressive environmental influences have an effect on the lifetime of conventional devices.

Technical details are as follows:

• Stroke up to 120 mm
• Angle range up to 95°
• Single acting and double acting
• Stored and freely definable characteristic curves
• Explosion protection according to CENELEC, FM and CSA
• Protection class IP65 and NEMA 4X
• Attachment kit for all common valve types
• Extremely low load
• Additional mechanical indicator
• Self-diagnostics as well as messages