Burkert 8791 REV.2 User manual

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

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

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Contents
1ABOUT THESE INSTRUCTIONS............................................................................................................8
1.1 Symbols........................................................................................................................................8
1.2 Denitionofterms........................................................................................................................8
2INTENDED USE ......................................................................................................................................9
3BASIC SAFETY INSTRUCTIONS .........................................................................................................10
4GENERAL INFORMATION....................................................................................................................11
4.1 Contactaddresses.....................................................................................................................11
4.2 Warranty .....................................................................................................................................11
4.3 InformationontheInternet........................................................................................................11
5DESCRIPTION OF SYSTEM.................................................................................................................12
5.1 Generaldescription....................................................................................................................12
5.1.1 Features ......................................................................................................................12
5.1.2 Combination with valve types and mounting versions...............................................13
5.1.3 Optionally external position feedback with inductive proximity switch......................13
5.1.4 Overview of the mounting options..............................................................................14
6STRUCTURE.........................................................................................................................................15
6.1 Representation...........................................................................................................................15
7FUNCTION............................................................................................................................................16
7.1 Functiondiagram .......................................................................................................................16
7.2 Functionofthepositioncontrol ................................................................................................17
7.2.1 Schematic representation of the position control.......................................................18
7.2.2 Functions of the position controller software .............................................................19
7.3 Interfacesofthepositioner ......................................................................................................21
8TECHNICAL DATA ................................................................................................................................22
8.1 Conformity..................................................................................................................................22
8.2 Standards ...................................................................................................................................22
ElectropneumaticpositionerType8791REV.2
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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eldbus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 Functions can be activated via communications software.........................................26
9OPERATING..........................................................................................................................................27
9.1 Safetyinstructions .....................................................................................................................27
9.2 Operatingstate .............................................................................................................................27
9.3 Controlanddisplayelementsofthepositioner........................................................................27
9.3.1 Congurationofthebuttons......................................................................................... 28
9.3.2 Function of the DIP switches........................................................................................ 29
9.3.3 Display of the LEDs ......................................................................................................30
9.3.4 Device status display..................................................................................................30
9.3.5 Status LED, green.......................................................................................................32
9.4 Errormessages.............................................................................................................................33
9.4.1 Messagesfordevicestatus„Outofspecication“ ....................................................33
9.4.2 Messages: Actuator moves to safety position ............................................................. 33
10 FUNCTIONS..........................................................................................................................................35
10.1 Basicfunctions.............................................................................................................................35
10.1.1 DIR.CMD -
Reversaloftheeectivedirectionofthepositionerset-pointvalue ..........................36
10.1.2 CUTOFF -
Sealing function for the positioner..............................................................................37
10.1.3 CHARACT -
Characteristic correction between input signal
(position set-point value) and stroke ..........................................................................38
10.1.4 INPUT -
Enterthestandardsignal(onlyvariantwithouteldbuscommunication) ..................40
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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eectivedirectionoftheactuator......................................................43
10.2.2 SPLTRNG -
Signal split range ........................................................................................................44
10.2.3 X.LIMIT -
Stroke limit..................................................................................................................45
10.2.4 X.TIME -
Limit actuating time ....................................................................................................46
10.2.5 X.CONTROL -
Parameterization of the positioner..............................................................................47
10.2.6 SAFEPOS -
Denitionofthesafeposition .....................................................................................47
10.2.7 SIG.ERROR -
Congurationofcablebreakdetection(onlyforvariantwithout
eldbuscommunication) ............................................................................................48
10.2.8 BINARY.IN (variant) -
Congurationofthedigitalinput(onlyforvariantwithout
eldbuscommunication) ............................................................................................48
10.2.9 OUTPUT (variant) -
Congurationoftheanalogoutput(onlyforvariantwithout
eldbuscommunication) ............................................................................................49
10.2.10 Setting the LED mode, device status .........................................................................49
11 ATTACHMENT AND ASSEMBLY ..........................................................................................................50
11.1 Safetyinstructions .....................................................................................................................50
11.2 AttachmenttoacontinuousvalvewithlinearactuatorsaccordingtoNAMUR......................51
11.2.1 Attachment kit (IEC 534-6) for linear actuators (order no. 787215) ............................51
11.2.2 Installation...................................................................................................................52
11.2.3 Attaching mounting bracket .......................................................................................54
11.2.4 Aligning lever mechanism...........................................................................................55
11.3 Attachmenttoacontinuousvalvewithrotaryactuator ...........................................................56
11.3.1 Attachment kit (VDI/VDE 3845) on rotary actuator (order no. 787338).......................56
11.3.2 Installation...................................................................................................................56
11.4 Remoteoperationwithexternalpositionsensor......................................................................59
11.4.1 Mounting accessories.................................................................................................59
11.4.2 Connection and start-up of the Remote-Sensor Type 8798 ......................................60
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12 FLUID CONNECTION ...........................................................................................................................61
12.1 Safetyinstructions .....................................................................................................................61
13 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 Pin assignment for output signals to the control centre (e.g. PLC), required for ana-
logue output variant only ............................................................................................64
13.2.4 Pin assignment for operating voltage.........................................................................65
13.3 Electricalconnectionwithcablegland .....................................................................................65
13.3.1 Designation of the screw-type terminals ....................................................................65
13.3.2 Connection of the screw-type terminals.....................................................................65
13.3.3 Terminal assignment for input signals from the control centre (e.g. PLC) ..................66
13.3.4 Terminal assignment for output signals to the control centre (e.g. PLC), for analogue
output variant only......................................................................................................66
13.3.5 Terminal assignment for external position sensor (for remote model only) ................67
14 ELECTRICALINSTALLATION,IO-LINK................................................................................................68
14.1 Pinassignmentforexternalpositionsensor(forremotemodelonly).....................................68
15 ELECTRICAL INSTALLATION, BÜS .....................................................................................................69
15.1 Pinassignmentforexternalpositionsensor(forremotemodelonly).....................................69
16 START-UP .............................................................................................................................................70
16.1 Safetyinstructions .....................................................................................................................70
16.2 Specifyingthestandardsettings ..............................................................................................70
16.2.1 Running the automatic adjustment X.TUNE .............................................................. 70
16.3 SettingwithBürkertCommunicator..........................................................................................71
16.3.1 Connecting IO-Link device with Bürkert Communicator............................................71
16.3.2 Connecting büS device with Bürkert Communicator .................................................72
17 IO-LINK .................................................................................................................................................73
17.1 Information,IO-Link ...................................................................................................................73
17.2 Technicalspecications,IO-Link ..............................................................................................73
17.2.1 Congurationoftheeldbus ......................................................................................73
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18 BÜS.......................................................................................................................................................74
18.1 Information,büS.........................................................................................................................74
18.2 Congurationoftheeldbus .....................................................................................................74
19 SERVICE ..............................................................................................................................................75
20 ACCESSORIES.....................................................................................................................................75
20.1 Communicationssoftware.........................................................................................................75
21 TRANSPORTATION, STORAGE, DISPOSAL........................................................................................76
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About these instructions
1 ABOUT THESE INSTRUCTIONS
The operating instructions describe the entire life cycle of the device.
→Keep these instructions ready to hand at the operation site.
Importantsafetyinformation.
▶Carefully read these instructions.
▶Observe in particular the safety instructions, intended use and operating conditions.
▶Persons, who work on the device, must read and understand these instructions.
1.1 Symbols
DANGER
Warnsofanimmediatedanger.
▶Failure to observe the warning will result in a fatal or serious injury.
WARNING
Warnsofapotentiallydangeroussituation.
▶Failure to observe the warning may result a fatal or serious injury.
CAUTION
Warnsofapossibledanger.
▶Failure to observe the warning may result in moderate or minor injuries.
ATTENTION
Warnsofdamagetoproperty.
▶Failure to observe the warning may result in damage to device or system.
Indicatesimportantadditionalinformation,tipsandrecommendations.
Referstoinformationintheseoperatinginstructionsorinotherdocumentation.
▶Indicates an instruction for risk prevention.
→Indicates a procedure which you must carry out.
Indicates a result.
Menu Indicates a interface text.
1.2 Denition 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”.
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Intended use
2 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uid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.
▶When using the device, observe the permitted data, operating conditions and application conditions.
This information can be found in the contractual documents, the operating instructions and on the type
label.
▶Use the device only in conjunction with third-party devices and components recommended and autho-
rized by Bürkert.
▶Do not use the device outdoors without protection from the weather.
▶In areas at risk of explosion, only use devices approved for use in those areas. These devices are
labeled with a separate Ex type label. For such use, note the information provided on the separate Ex
type label and the additional explosion-related information or separate explosion-related operating
instructions.
▶Pulsatingdirectvoltage(rectiedalternatingvoltagewithoutsmoothing)mustnotbeusedaspowersupply.
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Basic Safety Instructions
3 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-specic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othepressure.Ventordrainlines.
DANGER
Riskofinjuryfromelectricshock.
▶Beforeworkingonthedeviceorsystem,switchothepowersupply.Secureagainstreactivation.
▶Observe applicable accident prevention and safety regulations for electrical equipment.
Topreventinjury,ensurethefollowing:
▶Secure device or system to prevent unintentional activation.
▶Only trained technicians may perform installation and maintenance work.
▶Perform installation and maintenance with suitable tools only.
▶Do not make any changes to the device and do not subject it to mechanical stress.
▶Operate the device only in perfect state and in consideration of the operating instructions.
▶Observe the general rules of technology.
▶Install the device according to the regulations applicable in the respective country.
▶Donotfeedcorrosiveorammablemediaintothedeviceconnections.
▶Donotfeedanyuidsintotheconnectionsofthedevice.
▶After the process is interrupted, restart in a controlled manner. Observe sequence:
1. Connect electrical or pneumatic power supply.
2. Charge the device with medium.
▶Observe intended use.
ATTENTION!
Electrostaticsensitivecomponentsormodules.
Thedevicecontainselectroniccomponentswhichreactsensitivelytoelectrostaticdischarge(ESD).
Contactwithelectrostaticallychargedpersonsorobjectsishazardoustothesecomponents.Inthe
worstcasescenario,theywillbedestroyedimmediatelyorwillfailafterstart-up.
▶Observe the requirements in accordance with EN 61340-5-1 to minimise or avoid the possibility of dam-
age caused by sudden electrostatic discharge.
▶Also ensure that you do not touch electronic components when the power supply voltage is present.
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General Information
4 GENERAL INFORMATION
4.1 Contact addresses
Germany
Bürkert Fluid Control Systems
Sales Center
Christian-Bürkert-Str. 13-17
D-74653Ingelngen
Tel. + 49 (0) 7940 - 10 91 111
Fax + 49 (0) 7940 - 10 91 448
E-mail: [email protected]
International
Contactaddressescanbefoundonthenalpagesoftheseprintedoperatinginstructions.
And also on the internet at:
www.burkert.com
4.2 Warranty
ThewarrantyisonlyvalidifthepositionerType8791areusedasintendedinaccordancewiththespecied
application conditions.
4.3 Information on the Internet
The operating instructions and data sheets for Type 8791 can be found on the internet at:
www.burkert.com
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Description of System
5 DESCRIPTION OF SYSTEM
5.1 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.
The microprocessor electronics continuously compare the current position (actual value) with a set-point
positionvaluespeciedviathestandardsignalinputandsuppliestheresulttothepositioner.
Ifthereisacontroldierence,theelectropneumaticcontrolsystemcorrectstheactualpositionaccordingly.
5.1.1 Features
•Version
Positioner:
The position of the actuator is regulated according to the position set-point value. The position set-point
valueisspeciedbyanexternalstandardsignal(orviaeldbus).
•Positionsensor
- internal high resolution conductive potentiometer or
- external non-contact, non-wearing position sensor (remote).
•Microprocessor-controlledelectronics
for signal processing, control and valve control.
•Controlmodule
The device 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 dif-
ferent statuses of the device.
•Pilot valvesystem
The control system consists of 2 solenoid valves and 4 diaphragm reinforcers. In single-acting actuators
the working connection 2 must be sealed with a threaded plug.
•Position feedback
The feedback is implemented either via 2 proximity switches or via an 4 – 20 mA output (variant, without
eldbuscommunication)ordigitallyviaaeldbuscommunication(e.g.büS,IO-Link).
The operator can change the proximity switches or limit positions via control lugs.
•Pneumaticinterfaces
InternalthreadG1/4“
•Electricalinterfaces
Circular plug-in connector or cable gland
•Communicationsinterface
For exchanging process data and forcongurationandparameterization
•Housing
Plastic-coated aluminium housing with hinged cover and captive screws.
The housing of the positioner is protected from excessively high internal pressure, e.g. due to leaks, by a
pressure limiting valve.
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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dierentcontinuousvalves.Forexampleonvalveswith
linear (piston), membrane or rotary actuator. The actuators can be single-acting or double-acting.
•For single-acting actuators, only one chamber is aerated and deaerated during actuation. The generated
pressure works against a spring. The piston moves until there is an equilibrium of forces between com-
pressive force and spring force. To do this, one of the two air connections must be sealed with a threaded
plug.
•For double-acting actuators the chambers on both sides of the piston are pressurised. In this case, one
chamber is aerated when the other one is deaerated and vice versa. In this design, no spring is installed in
the actuator.
TwobasicdeviceversionsareoeredforthepositionerType8791;theydierintheattachmentoptionand
in the position sensor.
DeviceversionNAMUR:
An internal position sensor is used which is designed as a rotary potentiometer. The positioner is attached
directly to the actuator.
DeviceversionRemote:
An external position sensor (linear or rotative) via a digital interface. The positioner is attached to a wall
either with a standard rail or with a mounting bracket (remote design).
5.1.3 Optionally external position feedback with inductive proximity
switch
Thepositionertype8791canbettedwithanexternalpositionfeedback(seedatasheet/accessories).
The installation and the setting are described in the installation instructions which are enclosed with the
external position feedback.
The installation instructions can also be found on the Internet.
www.burkert.com →Type 8791
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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
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Structure
6 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.
The pilot valve system for single-acting and double-acting actuators consists of 2 solenoid valves.
6.1 Representation
Mechanical position indicator
Display module with 2 LEDs
Working connection 2
(connection: A2)
Supply pressure connection 1.4 – 7 bar
(connection: P)
Working connection 1
(connection: A1)
Air exhaust connection/
airexhaustlter
Internal position sensor
Axle for position sensor
Cable gland
Electronic module
Pilot valve system
Pressure-relief valve
Figure 1: Structure, positioner type 8791
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Function
7 FUNCTION
7.1 Function diagram
Diagram illustrating single-acting actuator
*Pilot valve system
1: Aeration valve
2: Bleed valve
Compressed-air
supply
Position
sensor
Positioner
Pilot valve
system*
1
2
Position set-
point value
Exhaust air
PositionerType8791 Controlvalvewith
single-actingactuator
Actual position
Figure 2: Function diagram, positioner type 8791
Theremotedesignhasthepositionsensorsituatedoutsidethepositionerdirectlyonthevalve
andisconnectedtothelatterbyacable.
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Function
7.2 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dierence
(Xd1), the actuator is aerated and deaerated via the control system. In this way the position of the actuator is
changeduntilcontroldierenceis0.Z1representsadisturbancevariable.
Valve opening
Control
valve
Pilot valve
system
Position sensor
PositionerPosition set-
point value
CMD Xd1 B1
E1
PK
Z1
POS
Position control circuit
+-
Figure 3: Signal ow plan of positioner
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Function
7.2.1 Schematic representation of the position control
büS, IO-Link 4 – 20 mA (factory setting) 0 – 20 mA
DIR.CMD SPLTRNG 1) CHARACT CUTOFF X.TIME 1)
DIR.ACT 1) X.LIMIT 1)
X.CONTROL DBND
POS
CMD*
CMD
1) Can be activated with communica-
tions software only
Figure 4: Schematic representation of position control
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Type 8791 REV.2

19
Function
7.2.2 Functions of the position controller software
Basicfunctions
•Activation via DIP switches
•Parameter setting via communications software
Function Eect
Sealing function
CUTOFF
Valve closes tight outside the control range. Speci-
cationofthevalue(as%)fromwhichtheactuator
iscompletelydeaerated(when0%)oraerated(when
100%)
(see chapter entitled “9.3.2FunctionoftheDIP
switches”).
Characteristic correction
CHARACT
Linearization of the operating characteristic can be
implemented
(see chapter entitled “9.3.2FunctionoftheDIP
switches”).
Reversaloftheeectivedirectionset-pointvalue
DIR.CMD
Reversaloftheeectivedirectionoftheset-point
value (see chapter entitled “9.3.2FunctionoftheDIP
switches”).
Table 2: Basic functions
Basicfunctions
•Activation with buttons or communications software
Function Eect
Standard signal2)
INPUT
Select set-point value standard signal.
Automatic calibration of the position controller
X.TUNE
Reset to factory settings
RESET
Reset to factory settings.
Table 3: Basic functions
2) Only adjustable with communications software
Only for variant without eldbus communication.
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Type 8791 REV.2

20
Function
Auxiliaryfunctions
•Activation and parameter setting with communications software
Function Eect
Reversaloftheeectivedirectionoftheactuator
DIR.ACT
Assignment of the aeration status of the actuator
chamber to the actual position.
Signal split range
SPLTRNG
Standardsignalas%forwhichthevalverunsthrough
the entire mechanical stroke range.
Stroke limit
X.LIMIT Limit the mechanical stroke range
Limit actuating time
X.TIME Limit the control speed
Control parameters
X.CONTROL Parameterize the position controller
Safety position
SAFEPOS Definition of the safety position
Cable break detection3)
SIG.ERROR Congurationofsignallevelfaultdetection
Digital input3)
BINARY.IN Congurationofthedigitalinput
Analog output3)
OUTPUT Congurationoftheanalogoutput(variant)
Table 4: Auxiliary functions
3) Only for variant without eldbus communication.
english
Type 8791 REV.2