Burkert Type 8694 is a compact digital electropneumatic positioner designed for integrated mounting on pneumatically controlled process control valves. The set-point value setting default occurs via standard signal 4-20 mA and/or via AS interface. A sensor element with contactless function records the valve spindle position. Simple start-up is achieved via the automatic TUNE function and setting with the aid of DIP switches.

Additional options are available for parametrizing using device DTM. A software interface can be used for the linearization of the operating characteristic with the aid of a freely programmable characteristic. The status indicator functions using LEDs, and an analogue position feedback can be optionally integrated.

Key Features

• Compact and robust stainless steel design
• Start-up with automatic TUNE function
• Contact-free position sensor
• Integrated pilot air duct in the actuator
• AS interface, IO-Link or Bürkert system bus (büS)

Structure

The positioner Type 8694 consists of the micro-processor controlled electronics, the position measuring system and the control system. The device is designed using three-wire technology. The positioner is operated via 2 keys and a 4-pole DIP switch. The pneumatic control system for single-acting actuators consists of 2 solenoid valves.

General Technical Data

Product properties	Description
Body Material	PPS, stainless steel
Seal Material	EPDM
Cover Material	PC
Operating keys	2
DIP switch	Integrated
Configuration tool	Bürkert Communicator
Initialisation	Automatically by X.TUNE function
Status display	Multicoloured LEDs
Measurement principle	Linear: inductive / Rotary: magnetic
Stroke range	Linear: 3...45 mm / Rotary: 30...180°
Operating voltage	24 V DC ± 25% (UL: NEC Class 2)
Power consumption	≤ 3.5 W
Protection class	III according to DIN EN 61140
Control medium	Neutral gases, air, quality class according to ISO 8573 - 1
Supply pressure	Low air capacity: 0...7 bar / High air capacity: 3...7 bar
Ambient temperature	-10...+60 °C
Degree of protection	IP65/IP67 according to EN 60529, 4X according to NEMA 250 Standard

Note

The supply pressure applied must be 0.5 to 1 bar above the minimum required pilot pressure of the valve actuator.

Dimensions

Mounting on ELEMENT control valve Type 23xx / 2103

(Dimensions in mm, unless otherwise stated)

Product Connections

Electrical connection: Without fieldbus communication 24 V DC

Pin	Pin assignment
1	Set-point + (0/4...20 mA)
2	Set-point GND
3	Operating voltage GND
4	Operating voltage + 24 V DC
5	Digital input +
6	Digital input GND
7	Analogue position feedback GND
8	Analogue position feedback + (option)

Performance Specifications

Signal flow diagram (Position control loop)

Additional software options of the TopControl BASIC positioner Type 8694 (extract)

• X.Tune function for automatic start-up
• Linear characteristic
• Close-tight function
• Reversal of the operating direction of the set-point signal
• Switching between manual and automatic mode
• Digital input
• Device operation via service büS interface and communicator
• Set-point value selection (0/4…20 mA)
• Position controller parametrisation
• Programmable stroke range limit
• Limitation of opening/closing time
• Safety position definition
• Signal error detection

Approvals and Conformities

• Explosion protection (Optional): ATEX II 3D Ex tc IIIC T135 °C Dc / II 3G Ex ec IIC T4 Gc; IECEx Ex tc IIIC T135 °C Dc / Ex ec IIC T4 Gc.
• North America (Optional): UL Listed for the USA and Canada (cULus certificate: E238179). FM Explosion Protection (Increased Safety for Class I, Zone 2).
• Others (Optional): China Compulsory Certification (CCC).