Burkert 8791 REV.2 Operating Instructions Manual
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Burkert 8791 REV.2 Operating Instructions Manual

Positioner sidecontrol basic electropneumatic positioner
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Type 8791 REV.2
Positioner SideControl BASIC
Electropneumatic positioner
STATUS
COM
Operating Instructions

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Summary of Contents for Burkert 8791 REV.2

  • Page 1 Type 8791 REV.2 Positioner SideControl BASIC Electropneumatic positioner STATUS Operating Instructions...
  • Page 2 We reserve the right to make technical changes without notice. Technische Änderungen vorbehalten. Sous réserve de modifications techniques. © Bürkert Werke GmbH & Co. KG, 2009 – 2020 Operating Instructions 2002/02_EU-EN_00815310 / Original DE...

  • Page 3: Table Of Contents

    Type 8791 REV.2 Electropneumatic positioner Type 8791 REV.2 ontents ABOUT THESE INSTRUCTIONS ......................8 Symbols ............................8 1.2 Definition of terms ........................8 INTENDED USE ............................9 BASIC SAFETY INSTRUCTIONS ......................10 GENERAL INFORMATION ........................11 4.1 Contact addresses ........................11 4.2 Warranty .............................11 4.3 Information on the Internet ......................11 DESCRIPTION OF SYSTEM .........................12 5.1 General description ........................12 5.1.1...
  • Page 4 Type 8791 REV.2 8.3 Operating conditions .........................22 8.4 Mechanical data .........................22 8.5 Type label ...........................23 8.6 Electrical data ..........................23 8.6.1 Electrical data, without fieldbus communication ............23 8.6.2 Electrical data, IO-Link ....................24 8.6.3 Electrical data, büS .....................24 8.7 Pneumatic data ..........................24 8.8 Safety end positions after failure of the electrical or pneumatic auxiliary power ....25 8.9 Factory settings of the positioner .....................26 8.9.1 Functions can be activated via DIP switches .............26 8.9.2...
  • Page 5 Type 8791 REV.2 10.1.5 RESET - Reset to factory settings .....................41 10.1.6 X.TUNE - Automatic calibration of the position controller to the relevant operating conditions 41 10.2 Additional functions ........................42 10.2.1 DIR.ACT - Reversal of the effective direction of the actuator ............43 10.2.2 SPLTRNG - Signal split range ......................44 10.2.3...
  • Page 6 Type 8791 REV.2 FLUID CONNECTION ...........................61 12.1 Safety instructions ........................61 ELECTRICAL INSTALLATION, WITHOUT FIELDBUS COMMUNICATION ..........63 13.1 Safety instructions ........................63 13.2 Electrical installation with circular plug-in connector .............63 13.2.1 Designation of the circular plug-in connector ............63 13.2.2 Pin assignment for input signals from the control centre (e.g. PLC) ......64 13.2.3...
  • Page 7 Type 8791 REV.2 BÜS ...............................74 18.1 Information, büS .........................74 18.2 Configuration of the fieldbus .....................74 SERVICE ..............................75 ACCESSORIES .............................75 20.1 Communications software ......................75 TRANSPORTATION, STORAGE, DISPOSAL ..................76 english...

  • Page 8: About These Instructions

    ▶ Indicates an instruction for risk prevention. → Indicates a procedure which you must carry out. Indicates a result. Menu Indicates a interface text. Definition of terms In these instructions the term “device” denotes the following device types: Positioner Type 8791 REV.2 The term “büS” (Bürkert system bus) used in this instruction stands for the communication bus developed by Bürkert and based on the CANopen protocol. In these instructions, the abbreviation “Ex” always refers to “potentially explosive area”. english...

  • Page 9: Intended Use

    Type 8791 REV.2 Intended use INTENDED USE The Positoner Type 8791 REV.2 is designed to be mounted on pneumatic actuators of process valves for the control of media. The permitted fluid media are listed in the technical data. ▶ Use the device for its intended purpose only. Non-intended use of the device may be dangerous to peo- ple, nearby equipment and the environment. ▶ Correct transportation, correct storage as well as correct installation, commissioning, operation and maintenance are essential for reliable and problem-free operation.

  • Page 10: Basic Safety Instructions

    Type 8791 REV.2 Basic Safety Instructions BASIC SAFETY INSTRUCTIONS These safety instructions do not consider any contingencies or incidents which occur during installation, operation and maintenance. The operator is responsible for observing the location-specific safety regulations, also with reference to the personnel. DANGER Risk of injury from high pressure and discharge of medium. ▶ Before working on the device or system, switch off the pressure. Vent or drain lines. DANGER Risk of injury from electric shock. ▶ Before working on the device or system, switch off the power supply. Secure against reactivation. ▶ Observe applicable accident prevention and safety regulations for electrical equipment.

  • Page 11: General Information

    Type 8791 REV.2 General Information GENERAL INFORMATION Contact addresses Germany Bürkert Fluid Control Systems Sales Center Christian-Bürkert-Str. 13-17 D-74653 Ingelfingen Tel. + 49 (0) 7940 - 10 91 111 Fax + 49 (0) 7940 - 10 91 448 E-mail: info@buerkert.com International Contact addresses can be found on the final pages of these printed operating instructions.

  • Page 12: Description Of System

    Type 8791 REV.2 Description of System DESCRIPTION OF SYSTEM General description The positioner Type 8791 is a digital, electropneumatic positioner for pneumatically actuated continuous valves. The device incorporates the main function groups - Position sensor - Pilot valve system (electropneumatic control system) - Microprocessor electronics The position sensor measures the current positions of the continuous valve.

  • Page 13: Combination With Valve Types And Mounting Versions

    Type 8791 REV.2 Description of System • Mounting on linear actuator according to NAMUR recommendation (DIN IEC 534-6) or on rotary actuator according to VDI/VDE 3845. • Optional Remote version for standard rail mounting or for mounting bracket 5.1.2 Combination with valve types and mounting versions The positioner Types 8791 can be mounted on different continuous valves. For example on valves with...

  • Page 14: Overview Of The Mounting Options

    Type 8791 REV.2 Description of System 5.1.4 Overview of the mounting options Mounting NAMUR on rotary actuator Mounting NAMUR with mounting bracket on a linear actuator Remote mounting with mounting bracket Remote mounting with standard rail Table 1: Overview of the mounting options...

  • Page 15: Structure

    Type 8791 REV.2 Structure STRUCTURE The positioner Type 8791 consist of the micro-processor controlled electronics, the position sensor and the pilot valve system. The unit is operated via 2 buttons and 4 DIP switches. 2 LEDs (1 RGB LED for device status and 1 green LED for communication interface status) indicate the dif- ferent statuses of the unit.

  • Page 16: Function

    Type 8791 REV.2 Function FUNCTION Function diagram Diagram illustrating single-acting actuator Compressed-air Control valve with supply Positioner Type 8791 single-acting actuator Position set- point value Positioner Pilot valve system* Exhaust air Position sensor Actual position * Pilot valve system 1: Aeration valve 2: Bleed valve...

  • Page 17: Function Of The Position Control

    Type 8791 REV.2 Function Function of the position control The position sensor records the current position (POS) of the pneumatic actuator. The positioner compares this actual position value with the set-point value (CMD) which is a standard signal. If there is a control difference (Xd1), the actuator is aerated and deaerated via the control system. In this way the position of the actuator is changed until control difference is 0. Z1 represents a disturbance variable.

  • Page 18: Schematic Representation Of The Position Control

    Type 8791 REV.2 Function 7.2.1 Schematic representation of the position control 1) Can be activated with communica- tions software only Figure 4: Schematic representation of position control english...

  • Page 19: Functions Of The Position Controller Software

    Type 8791 REV.2 Function 7.2.2 Functions of the position controller software Basic functions • Activation via DIP switches • Parameter setting via communications software Function Effect Sealing function Valve closes tight outside the control range. Speci- fication of the value (as %) from which the actuator CUTOFF is completely deaerated (when 0%) or aerated (when 100%) (see chapter entitled “9.3.2 Function of the DIP switches”).
  • Page 20 Type 8791 REV.2 Function Auxiliary functions • Activation and parameter setting with communications software Function Effect Reversal of the effective direction of the actuator Assignment of the aeration status of the actuator chamber to the actual position. DIR.ACT Signal split range Standard signal as % for which the valve runs through the entire mechanical stroke range. SPLTRNG...

  • Page 21: Interfaces Of The Positioner

    Type 8791 REV.2 Function Interfaces of the positioner Input for position Analog position set-point value feedback 4 – 20 mA (variant) Positioner 0 – 20 mA 3- or 4-wire Proximity switch 1, Digital input Proximity switch 2 24 V PNP NO...

  • Page 22: Technical Data

    Type 8791 REV.2 Technical data TECHNICAL DATA Conformity In accordance with the EU Declaration of conformity, the positioner Type 8791 is compliant with the EU Directives (if applicable). Standards The applied standards on the basis of which compliance with the EU Directives is confirmed are listed in the EU type examination certificate and/or the EU Declaration of Conformity (if applicable). Operating conditions WARNING! Solar radiation and temperature fluctuations may cause malfunctions or leaks. ▶ If the device is used outdoors, do not expose it unprotected to the weather conditions.

  • Page 23: Type Label

    Type 8791 REV.2 Technical data Type label Type Operating voltage Nominal power Device variant, communication, version 8791 24V DC 5W Operating pressure, degree of protection Remote IO-Link REV.2 Ambient temperature P=1.4...7bar IP65/67 Tamb –10...+60°C Approval marking CSA (for Canada and USA) ®...

  • Page 24: Electrical Data, Io-Link

    Type 8791 REV.2 Technical data 8.6.2 Electrical data, IO-Link Protection class III as per DIN EN 61140 (VDE 0140-1) Connection Circular plug-in connector M12 x 1, 5-pin, A-coded, Port Class B Operating voltage System supply (Pin 1+3) 24 V DC ±25 % (according to specification) Actuator supply (Pin 2+5) 24 V DC ±25 % (according to specification) Current consumption System supply (Pin 1+3) max.

  • Page 25: Safety End Positions After Failure Of The Electrical Or Pneumatic Auxiliary Power

    Type 8791 REV.2 Technical data Safety end positions after failure of the electrical or pneumatic auxiliary power The safety end position depends on the fluid connection of the actuator to the working connections A1 or A2. Safety end positions after failure of the Actuator system Designation pneumatic electrical auxiliary power auxiliary power down single-acting → Connection according to “Figure 7” down Control function down → Connection according to “Figure 8”...

  • Page 26: Factory Settings Of The Positioner

    Type 8791 REV.2 Technical data Factory settings of the positioner 8.9.1 Functions can be activated via DIP switches Function Parameter Value CUTOFF Sealing function below Sealing function above 98 % CHARACT Characteristic correction FREE DIR.CMD Reversal of the effective direction set- point value Table 6: Factory settings 8.9.2...

  • Page 27: Operating

    Type 8791 REV.2 Operating OPERATING Safety instructions WARNING! Risk of injury from improper operation! Improper operation may result in injuries as well as damage to the unit and the area around it. ▶ The operating personnel must know and have understood the contents of the operating instructions.

  • Page 28: Configuration Of The Buttons

    Type 8791 REV.2 Operating 9.3.1 Configuration of the buttons To operate the DIP switches and buttons, make sure that the local control lock is deactivated/ unlocked (factory setting): with communication software or fieldbus communication. The configuration of the 2 buttons inside the housing varies depending on the operating state (AUTOMATIC/ MANUAL). The description of the operating state (AUTOMATIC/MANUAL) can be found in the chapter entitled “9.2 Operating state”. Button 1 LED 1 LED 2 Button 2 Figure 11: Description of the buttons →...

  • Page 29: Function Of The Dip Switches

    Type 8791 REV.2 Operating 9.3.2 Function of the DIP switches To operate the DIP switches and buttons, make sure that the local control lock is deactivated/ unlocked (factory setting): with communication software or fieldbus communication. 1 2 3 4 → To operate the buttons and DIP switches, unscrew the 4 screws on the housing cover and remove the housing cover. DIP Switches Position Function Reversal of the effective direction of the set-point value (DIR.CMD)

  • Page 30: Display Of The Leds

    Type 8791 REV.2 Operating 9.3.3 Display of the LEDs LED 1 LED 2 Figure 12: LED display LED 1 Display of the device status and valve position (RGB) LED 2 Display of the bus status (green) Display during functions • X.TUNE •...
  • Page 31 Type 8791 REV.2 Operating 9.3.4.1 Valve mode Displays in valve mode: • Valve position: open, half-way, closed • Device status: Error Valve position Valve position Device status: Error status, color status, color Open is lit yellow* flashes red alternately with yellow* Half-way LED off* flashes red alternately with LED off* Closed is lit green*...

  • Page 32: Status Led, Green

    Type 8791 REV.2 Operating 9.3.4.3 NAMUR mode The device status LEDs (top LED) show the device status. The display elements change color in accordance with NAMUR NE 107. If several device statuses exist simultaneously, the device status with the highest priority is displayed. The priority is determined by the severity of the deviation from controlled operation (red LED = failure = highest priority).

  • Page 33: Error Messages

    Type 8791 REV.2 Operating Error messages 9.4.1 Messages for device status „Out of specification“ Message Description Procedure Temperature limit Ambient temperature is too Reduce ambient temperature. If problems exceeded high continue, contact your Bürkert Service Center Temperature limit not Ambient temperature is too low Increase ambient temperature...
  • Page 34 Type 8791 REV.2 Operating IO-Link error No valid process data is - Check connection to the IO-Link master received - Check whether valid setpoints are sent to the device via the IO-Link interface X.TUNE error occurred The last X.TUNE was not -Check compressed air supply successful.

  • Page 35: Functions

    Type 8791 REV.2 Functions FUNCTIONS The positioner type 8791 has different basic and additional functions which can be configured and param- eterized via the DIP switches or the communications software. 10.1 Basic functions The following basic functions can be activated via the DIP switches (CUTOFF and CHARACT) or changed (DIR.CMD). The parameters for the sealing function (CUTOFF) and characteristic correction (CHARACT) are set using the communication software.

  • Page 36: Dir.cmd

    Type 8791 REV.2 Functions 10.1.1 DIR.CMD - Reversal of the effective direction of the positioner set-point value Use this function to set the effective sense of direction between the input signal (INPUT) and the set-point position of the actuator. Factory settings: DIP switch set to OFF (ascending) DIP switches Position Function Reversal of the effective sense of direction of the set-point value (DIR.CMD) (Set-point value 20 – 4 mA corresponds to position 0 – 100 %), descending Normal effective sense of direction of the set-point value (Set-point value 4 – 20 mA corresponds to position 0 – 100 %), ascending Table 20: DIP switches 1 The effective sense of direction (DIR.CMD) can be changed only via DIP switch 1 in the positioner.

  • Page 37: Cutoff

    Type 8791 REV.2 Functions 10.1.2 CUTOFF - Sealing function for the positioner This function causes the valve to be sealed outside the control range. Controlled operation is resumed with a hysteresis of 1 %. Factory settings: DIP switch 2 set to OFF (no sealing function) DIP switches Position Function Sealing function active.

  • Page 38: Charact

    Type 8791 REV.2 Functions 10.1.3 CHARACT - Characteristic correction between input signal (position set-point value) and stroke Characteristic (customer-specific characteristic) This function can be used to activate a transfer characteristic with respect to set-point value (set-point position) and valve stroke for correction of the flow or operating characteristic. The transfer characteristic can be changed via the communications software only. Factory settings: DIP switch 3 set to OFF (linear)
  • Page 39 Type 8791 REV.2 Functions The flow characteristic k = f(s) indicates the flow-rate of a valve, expressed by the value k as a function of the stroke s of the actuator spindle. It is determined by the design of the valve seat and the seat seal. In general two types of flow characteristics are implemented, the linear and the equal percentage. In the case of linear characteristics, equal k value changes dk are assigned to equal stroke changes ds.

  • Page 40: Input

    Type 8791 REV.2 Functions Entering the freely programmable characteristic The characteristic is defined by 21 nodes distributed uniformly over the position set-point values ranging from 0 – 100%. They are spaced at intervals of 5%. A freely selectable stroke (adjustment range 0 – 100%) is assigned to each node. The difference between the stroke values of two adjacent nodes must not be greater than 20%. Example of a programmed characteristic Valve stroke [&] Unit signal [%] 90 100 4 – 20 mA 0 – 20 mA Figure 16: Example of a programmed characteristic 10.1.4 INPUT - Enter the standard signal (only variant without fieldbus communication) Under this menu option, enter the input signal used for the set-point value.

  • Page 41: Reset

    Type 8791 REV.2 Functions 10.1.5 RESET - Reset to factory settings This function can be used to reset the positioner to the factory settings. 10.1.6 X.TUNE - Automatic calibration of the position controller to the relevant operating conditions The X.TUNE function must be run for a function check of the positioner to adjust to specific local features.

  • Page 42: Additional Functions

    Type 8791 REV.2 Functions 10.2 Additional functions The following additional functions can be configured and parameterized via the communications software: Function Description Reversal of the effective Assignment of the aeration status of the actuator chamber to the actual direction of the actuator position DIR.ACT Signal split range Signal split range; input signal as a % for which the valve runs through the entire stroke range. SPLTRNG Stroke limit Limit the mechanical stroke range X.LIMIT...

  • Page 43: Dir.act

    Type 8791 REV.2 Functions 10.2.1 DIR.ACT - Reversal of the effective direction of the actuator Use this function to set the effective direction between the aeration state of the actuator and the actual position. Factory setting: Off (rise) Rise: Direct effective direction (deaerated → 0 %; aerated 100 %) Case: Inverse effective direction (deaerated → 100 %; aerated 0 %) Actual position increasing decreasing Aeration state deaerated aerated Figure 17: DIR.ACT graph english...

  • Page 44: Spltrng

    Type 8791 REV.2 Functions 10.2.2 SPLTRNG - Signal split range Minimum and maximum values of the input signal as a % for which the valve runs through the entire stroke range. Factory setting: Lower signal range split = 0 %; Upper signal range split = 100 % Lower value split range: I nput the minimum value of the input signal as a % Adjustment range: 0 – 75 % Upper value split range: I nput the maximum value of the input signal as a % Adjustment range: 25 – 100 % Use this function to limit the position set-point value range of the positioner by specifying a minimum and a maximum value. This makes it possible to divide a unit signal range that is used (4 – 20 mA, 0 – 20 mA) into...

  • Page 45: X.limit - Stroke Limit

    Type 8791 REV.2 Functions 10.2.3 X.LIMIT - Stroke limit This function limits the (physical) stroke to specified % values (lower and upper). In doing so, the stroke range of the limited stroke is set equal to 100 %. If the limited stroke range is left during operation, negative actual positions or actual positions greater than 100 % are shown. Factory setting: Lower position limit = 0 %, upper position limit = 100 % Adjustment ranges: Lower position limit: 0 – 50 % of the entire stroke Upper position limit: 50 – 100 % of the entire stroke The minimum distance between the upper and lower stroke limit is 50 %. Therefore if one value is entered with a minimum distance of < 50 % the other value is adjusted automatically. Limited Physical stroke (%) stroke (%) Unlimited stroke Limited stroke Set-point value [mA] (INPUT) Figure 19: X.LIMIT graph english...

  • Page 46: X.time

    Type 8791 REV.2 Functions 10.2.4 X.TIME - Limit actuating time Use this function to specify the opening and closing times for the entire stroke and thereby limit control speeds. When the X.TUNE function is running, the minimum opening and closing time for the entire stroke is automatically entered for Open and Close. Therefore, movement can be at maximum speed. Factory setting: values determined at the factory by the X.TUNE function If the control speed will be limited, values can be input for Open and Close which are between the minimum values determined by the X.TUNE and 60 seconds.

  • Page 47: X.control

    Type 8791 REV.2 Functions 10.2.5 X.CONTROL - Parameterization of the positioner Use this function to set the parameters for the positioner (dead band and amplification factors (kp)). Deadband: Insensitivity range of the positioner Entry for the deadband as a % in reference to the scaled stroke range; i.e. X.LIMIT upper stroke limit - X.LIMIT lower stroke (see auxiliary function X.LIMIT). This function causes the controller to respond only beginning at a specific control difference. This function saves wear on the solenoid valves in the positioner and the pneumatic actuator.

  • Page 48: Sig.error

    Type 8791 REV.2 Functions 10.2.7 SIG.ERROR - Configuration of cable break detection (only for variant without fieldbus communication) The cable break detection function (SIG.ERROR) is used to detect a fault on the input signal. Cable break detection can be selected for a 4 – 20 mA signal only: Fault if input signal ≤ 3.5 mA (± 0.5 % of final value, hysteresis 0.5 % of final value) If 0 – 20 mA is selected, cable break detection cannot be selected. A signal error is indicated on the device by the LED 1 for activated cable break detection (error or out of spezification).

  • Page 49: Output (Variant)

    Type 8791 REV.2 Functions 10.2.9 OUTPUT (variant) - Configuration of the analog output (only for variant without fieldbus communication) The function analog output (OUTPUT) only appears in the selection of functions if the positioner has an analog output (variant) or if no parameters have been read in yet.

  • Page 50: Attachment And Assembly

    Type 8791 REV.2 Attachment and assembly ATTACHMENT AND ASSEMBLY The dimensions of the positioner and the different device versions can be found on the data sheet. 11.1 Safety instructions WARNING! Risk of injury from improper installation. ▶ Installation may be carried out by authorised technicians only and with the appropriate tools. Risk of injury from unintentional activation of the system and an uncontrolled restart. ▶ Secure system from unintentional activation. ▶ Following assembly, ensure a controlled restart.

  • Page 51: Attachment To A Continuous Valve With Linear Actuators According To Namur

    Type 8791 REV.2 Attachment and assembly 11.2 Attachment to a continuous valve with linear actuators according to NAMUR The valve position is transferred to the position sensor installed in the positioner via a lever (according to NAMUR). 11.2.1 Attachment kit (IEC 534-6) for linear actuators (order no.

  • Page 52: Installation

    Type 8791 REV.2 Attachment and assembly 11.2.2 Installation WARNING! Risk of injury from improper installation. ▶ Installation may be carried out by authorised technicians only and with the appropriate tools. Risk of injury from unintentional activation of the system and an uncontrolled restart. ▶ Secure system from unintentional activation. ▶ Following assembly, ensure a controlled restart. Procedure: ②...
  • Page 53 Type 8791 REV.2 Attachment and assembly Figure 23: Assembling the lever The gap between the driver pin and the axle should be the same as the drive stroke. This results in the ideal angular range of the lever of 60° (see “Figure 24”). Angular range of the position sensor: The maximum angular range of the position sensor is 150°. Rotational range of the lever: To ensure that the position sensor operates at a good resolution, the rotational range of the lever must be at least 30°. The rotational movement of the lever must be within the position sensor angular range of 150°. The scale printed on the lever is not relevant. 150° Maximum rota- tional range of the...

  • Page 54: Attaching Mounting Bracket

    Type 8791 REV.2 Attachment and assembly 11.2.3 Attaching mounting bracket ① ⑨ ⑩ → Attach mounting bracket to the back of the positioner with hexagon bolts , circlip ⑪ washers  (see “Figure 25”). The selection of the M8 thread used on the positioner depends on the size of the actuator. → To determine the correct position, hold the positioner with mounting bracket on the actuator.

  • Page 55: Aligning Lever Mechanism

    Type 8791 REV.2 Attachment and assembly Attaching the positioner with mounting bracket for actuators with columnar yoke: ⑦ ⑪ ⑩ → Attach mounting bracket to the columnar yoke with the U-bolt , washers , circlips and hexagon nuts (see “Figure 27”). Figure 27: Attach positioner with mounting bracket; for actuators with columnar yoke 11.2.4...

  • Page 56: Attachment To A Continuous Valve With Rotary Actuator

    Type 8791 REV.2 Attachment and assembly 11.3 Attachment to a continuous valve with rotary actuator The axle of the position sensor integrated in the positioner is connected directly to the axle of the rotary actuator. 11.3.1 Attachment kit (VDI/VDE 3845) on rotary actuator (order no.
  • Page 57 Type 8791 REV.2 Attachment and assembly Anti-twist safeguard: Note the flat side of the axle. One of the setscrews must be situated on the flat side of the axle as an anti-twist safeguard (see “Figure 28”). Angular range of the position sensor: The maximum angular range of the position sensor is 150°. The axle of the positioner may be moved within this range only. ① → Connect adapter to the axle of the positioner and secure with 2 setscrews. → Secure setscrews with self-locking nuts to prevent them from working loose.
  • Page 58 Type 8791 REV.2 Attachment and assembly ① ④ ③ Figure 29: Attach assembly bridge (schematic representation) → Place positioner with assembly bridge on the rotary actuator and attach (see “Figure 30”). Figure 30: Rotary actuator attachment english...

  • Page 59: Remote Operation With External Position Sensor

    Type 8791 REV.2 Attachment and assembly 11.4 Remote operation with external position sensor In the case of this model the positioner has no position sensor in the form of a rotary position sensor, but an external remote sensor. The Remote-Sensor Type 8798 is connected via a serial, digital interface.

  • Page 60: Connection And Start-Up Of The Remote-Sensor Type 8798

    Type 8791 REV.2 Attachment and assembly 11.4.2 Connection and start-up of the Remote-Sensor Type 8798 WARNING! Risk of injury from improper start-up. ▶ Start-up may be carried out by authorised technicians only and with the appropriate tools. Risk of injury from unintentional activation of the system and an uncontrolled restart. ▶ Secure system from unintentional activation. ▶ Following assembly, ensure a controlled restart.

  • Page 61: Fluid Connection

    Type 8791 REV.2 Fluid connection FLUID CONNECTION 12.1 Safety instructions DANGER! Risk of injury from high pressure in the equipment/device. ▶ Before working on equipment or device, switch off the pressure and deaerate/drain lines. WARNING! Risk of injury from improper installation. ▶ Installation may be carried out by authorized technicians only and with the appropriate tools. Risk of injury from unintentional activation of the system and an uncontrolled restart. ▶ Secure system from unintentional activation. ▶ Following installation, ensure a controlled restart.
  • Page 62 Type 8791 REV.2 Fluid connection Procedure: → Apply supply pressure (1.4 – 7 bar) to the supply pressure connection P. For single-acting actuators (Control function A and B): → Connect one working connection (A1 or A2, depending on required safety end position) to the chamber of the single-acting actuator.

  • Page 63: Electrical Installation, Without Fieldbus Communication

    Type 8791 REV.2 El e ctri c al i n stal l a ti o n, wi t hout fi e l d bus communi c ati o n ELECTRICAL INSTALLATION, WITHOUT FIELDBUS COMMUNICATION All electrical inputs and outputs of the device are not galvanically isolated from the supply voltage.

  • Page 64: Pin Assignment For Input Signals From The Control Centre (E.g. Plc)

    Type 8791 REV.2 El e ctri c al i n stal l a ti o n, wi t hout fi e l d bus communi c ati o n 13.2.2 Pin assignment for input signals from the control centre (e.g.

  • Page 65: Pin Assignment For Operating Voltage

    Type 8791 REV.2 El e ctri c al i n stal l a ti o n, wi t hout fi e l d bus communi c ati o n 13.2.4 Pin assignment for operating voltage Wire color* Configuration External circuit / Signal level green 24 V DC ± 25% max. residual ripple 10%...

  • Page 66: Terminal Assignment For Input Signals From The Control Centre (E.g. Plc)

    Type 8791 REV.2 El e ctri c al i n stal l a ti o n, wi t hout fi e l d bus communi c ati o n 13.3.3 Terminal assignment for input signals from the control centre (e.g. PLC)

  • Page 67: Terminal Assignment For External Position Sensor (For Remote Model Only)

    Type 8791 REV.2 El e ctri c al i n stal l a ti o n, wi t hout fi e l d bus communi c ati o n Terminal assignment for operating voltage Terminal Configuration External circuit / Signal level +24 V Operating voltage + +24 V 24 V DC ± 25%...

  • Page 68: Electrical Installation, Io-Link

    Type 8791 REV.2 Electrical installation, IO-Link ELECTRICAL INSTALLATION, IO-LINK Designation Configuration 24 V DC System supply 24 V DC Actuator supply L – 0 V (GND) System supply IO-Link 0 V (GND) Actuator supply Table 37: Pin assignment 14.1 Pin assignment for external position sensor...

  • Page 69: Electrical Installation, Büs

    Type 8791 REV.2 Electrical Installation, büS ELECTRICAL INSTALLATION, BÜS Wire color Configuration CAN plate/shielding CAN plate/shielding +24 V DC ±25%, max. residual ripple 10% black GND / CAN_GND white CAN_H blue CAN_L Table 40: Pin assignment For electrical installation with büS network, note: Use a 5-pin round plug and shielded 5-core cable. The shielding is capacitively connected to the functional earth via the device.

  • Page 70: Start-Up

    Type 8791 REV.2 Start-up START-UP 16.1 Safety instructions WARNING! Risk of injury from improper operation. Improper operation may result in injuries as well as damage to the device and the area around it. ▶ Before start-up, ensure that the operating personnel are familiar with and completely understand the contents of the operating instructions.

  • Page 71: Setting With Bürkert Communicator

    Type 8791 REV.2 Start-up → Start X.TUNE by pressing button 1 for 5 sec LED 2 flashes at 5 Hz. The device is in the NAMUR state function check, LED 1 lights orange. If the X.TUNE is successfully completed, the NAMUR state is reset again. The changes are automatically transferred to the memory (EEPROM) provided the X.TUNE function is successful.

  • Page 72: Connecting Büs Device With Bürkert Communicator

    Type 8791 REV.2 Start-up → Insert micro USB plug in communications interface. → Establish connection to PC with USB-büS interface set. → Starting Bürkert Communicator. → Implementing settings. 16.3.2 Connecting büS device with Bürkert Communicator Required components: • Communications software: Bürkert Communicator for PC •...

  • Page 73: Io-Link

    Type 8791 REV.2 IO-Link IO-LINK 17.1 Information, IO-Link IO-Link is an internationally standardized IO technology (IEC 61131-9) to enable sensors and actuators to communicate. IO-Link is a point-to-point communication with 3-wire connection technology for sensors and actuators and unshielded standard sensor cables.

  • Page 74: 18 Büs

    Type 8791 REV.2 büS BÜS 18.1 Information, büS büS is a system bus developed by Bürkert with a communication protocol based on CANopen. 18.2 Configuration of the fieldbus The required start-up files and the description of objects are available on the Internet. Download from: www.burkert.com / Type 8791 / Software english...

  • Page 75: Service

    Type 8791 REV.2 Service SERVICE If the positioner type 8791 is operated according to the instructions in this manual, it is maintenance-free. ACCESSORIES CAUTION! Risk of injury and/or damage by the use of incorrect parts. Incorrect accessories and unsuitable replacement parts may cause injuries and damage the device and the surrounding area.

  • Page 76: Transportation, Storage, Disposal

    Type 8791 REV.2 Transportation, storage, disposal TRANSPORTATION, STORAGE, DISPOSAL NOTE Damage in transit due to inadequately protected devices. ▶ Protect the device against moisture and dirt in shock-resistant packaging during transportation. ▶ Observe permitted storage temperature. NOTE Incorrect storage may damage the device. ▶ Store the device in a dry and dust-free location.
  • Page 77 www.burkert.com...

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