8635 S/HART/PROFIBUS PA type side control positioner

8635 S/HART/PROFIBUS PA type side control positioner

Digital electrical positioner for pneumatic valves with piston or rotary actuators

The 8635 S/HART or 8635 PA side control positioner is suitable for pneumatic valves with piston or rotary actuators. The positioner is a two-wire system, and the 4-20 mA input signal is input to the set value while powering the entire positioner. Communication is possible via the HART protocol or PROFIBUS PA. An optional intrinsically safe (EEx ia) positioner is available for use in areas where explosion hazards are present (Zone 1 of the ATEX standard).
Microprocessor-controlled electronics perform signal processing, closed-loop control, and control of internal drive systems. The X-TUNE software feature allows the positioner to automatically adjust to the valve being controlled. Programming and operation can be easily done with three operating keys and text display, HART protocol or PROFIBUS PA. A process controller with a PID response can also be installed on the positioner. At this point, the process control loop is connected in series with the position control loop.

The positioner is compact and rugged for chemical engineering and process.

8635 S/HART/PA type side control positioner features

The electrical system is two-wire: powered by a 4-20 mA signal or PROFIBUS PA.
Optional ATEX EEx ia IIC T4/T5/T6
(Intrinsically Safe) type, used in areas where explosion is dangerous.
Optional with PID process controller.
The parameters of the PID process controller can be set automatically (S/HART).
Robust construction for harsh environments.
The display and operating buttons are inside the cover for good protection.
Mounted on actuators and regulators using standard NAMUR and DIN IEC mounts.
Up to two triggers can be selected as limit switches.
The pneumatic drive system uses a large flow rate (55-170 NI/min), which itself does not consume air.
The limit screw can be used to adjust the air supply flow of the actuator.
Purging the surface of the positioner with clean compressed air prevents condensation from forming and prevents the surrounding atmosphere from entering the positioner.
A stainless steel pressure gauge can be installed on the positioner to measure the air supply pressure and/or internal pressure.
The operating principle and software structure are the same as the Model 8630 Continuous Top Control Positioner and the 1067 Side Control Positioner.