Burkert 8681 User manual

www.burkert.com
We reserve the right to make
technical changes without notice.
Technische Änderungen
vorbehalten.
Sous réserve de modifications
techniques.
© 2010 - 2011 Bürkert Werke GmbH
Operating Instructions
1105/02_EU-ml_00806166 / Original DE
Type 8681
Control Head
Steuerkopf
Tête de commande
Quickstart
2
THE QUICKSTART1.
WARNING!
Important safety information!
Read quickstart carefully and thoroughly. Study in par-
ticular the chapters entitled 4. Basic Safety Instructions
and 3. Authorized use.
The operating instructions must be read and understood.•
Quickstart explains, for example, how to install and start-up
the device.
The detailed description of the device can be found in the
operating instructions for Control Head Type 8681.
The operating instructions can be found on the
Internet at:
www.burkert.com Documentation Type 8681
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SYMBOLS2.
The following symbols are used in these instructions.
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 in serious• injuries or death.
CAUTION!
Warns of a possible danger!
Failure to observe this warning may result in a moderate• or minor injury.
NOTE!
Warns of damage to property!
Important tips and recommendations for safe and
the flawless functioning of the device.
designates a procedure which you must carry out.

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3. AUTHORIZED USE
Non-authorized use of the Control Head Type 8681
may be a hazard to people, nearby equipment and
the environment.
The Control Head has been designed for use as• actuation of pneumatically operated process valves
and / or for recording the switching states of these.
Use according to the authorized data, operating condi-• tions and conditions of use specified in the contract
documents and operating instructions.
In view of the large number of options for use it might• be necessary to test prior to installation whether the
control head is suitable for the concrete use.
If you have any questions, please contact your Bürkert
Service Center.
The device may be used only in conjunction with third-• party devices and components recommended and
authorized by Burkert.
Any unauthorized reconstructions and changes to the• control head are prohibited for safety reasons.
Correct transportation, correct storage and installation• and careful use and maintenance are essential for
reliable and faultless operation.
For connecting the control head, use line installations• that do not cause any mechanical stresses.
Use the device only as intended.•
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Predictable Misuse3.1.
Do not supply the medium connectors of the system with•
aggressive or flammable media.
Do not supply the medium connectors with any liquids.•
Do not physically stress the housing (e.g. by placing objects•
on it or standing on it, or using it as attachment point for
transport work).
Do not make any external modifications to the device•
housings. Do not paint the housing parts or screws.
In the explosion-risk area, only wipe the control head with a•
damp or anti-static cloth to avoid electro-static charges!
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4. BASIC SAFETY
INSTRUCTIONS
These safety instructions do not make allowance for any
contingencies and events which may arise during the instal-•
lation, operation and maintenance of the devices.
local safety regulations - the operator is responsible for•
observing these regulations, also with reference to the
installation personnel.
DANGER!
Danger – high pressure!
Before loosening pneumatic lines and valves, turn off• the pressure and vent the lines.
Danger of explosion in explosive atmosphere (only in
the event of a fault as zone 2)!
Opening the hood or the housing in an explosive atmo-• sphere is only allowed in the isolated state!
WARNING!
Risk of electric shock!
Before reaching into the system (except for the• Teach-In procedure in a non-explosive atmosphere)
switch off the power supply and secure it to prevent
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restarting!
Observe applicable accident prevention and safety• regulations for electrical equipment!
WARNING!
General Hazardous Situations.
To prevent injuries, ensure that:
the system cannot be activated unintentionally.•
installation and maintenance work, as well as operator• control actions may be carried out by authorized, quali-
fied technicians only and with the appropriate tools.
after an interruption in the power supply or pneu-• matic supply, ensure that the process is restarted in a
defined or controlled manner.
the device may be installed and operated only when in• perfect condition and in consideration of the operating
instructions.
the general rules of technology apply to application• planning and operation of the device.
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NOTE!
Electrostatic sensitive components / modules!
The device contains electronic components, which react•
sensitively to electrostatic discharge (ESD). Contact
with electrostatically charged persons or objects may
be 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 DIN EN•
61340-5-1 and 5-2 to minimize or avoid the possibility of
damage caused by sudden electrostatic discharge!
Also, ensure that you do not touch electronic components•
when the power supply voltage is present!
Control Head Type 8681 was developed with due
consideration given to accepted safety rules and
is state-of-the-art. Nevertheless, dangerous situa-
tions may occur.
Failure to observe this operating manual and its oper-
ating instructions as well as unauthorized tampering with
the device release us from any liability and also invalidate
the warranty covering the devices and accessories!
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Explosive Atmosphere4.1.
NOTE!
Operation of the Control Head in Explosive
Atmosphere
The housing may not be opened when devices are•
charged! It should be secured against unintentional
opening using plastic self-cutting screws or seal (or
comparable)!
Layers of dust on the housing may not exceed 5 mm!•
Lint, conductive and non-conductive dust particles are
allowed.
The inside of the housing may not be dirty!
Activating the DIP switches on the circuit board, using•
the service plug and the Teach buttons is not allowed in
explosive atmosphere!
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GENERAL INFORMATION5.
Scope of Supply5.1.
Check immediately upon receipt of the delivery that the con-
tents are not damaged and that the type and scope agree
with the delivery note and packing list.
If there are any discrepancies, please contact us immedi-
ately.
Contact address5.2.
Germany:
Bürkert Fluid Control Systems
Sales Center
Christian-Bürkert-Straße 13-17
D-74653 Ingelfingen
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
International:
The contact addresses can be found on the Internet at:
www.burkert.com Bürkert Company Locations
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STRUCTURE AND FUNCTION6.
The Control Head Type 8681 has been designed for use
as actuation of pneumatically operated process valves and/
or for recording the switching states of these.
For the recording and feedback of the process valve
switching positions to a higher-level control, the control
head has been equipped with a contactless position mea-
suring system, which works with three discrete, adjustable
feedback signals (Teach-In Function).
Various pneumatic and electrical connection variants are
available.
Positions and status information can be indicated by means
of three signal colors.
Manual Control6.1.
Standardly, the control head provides the following:
a magnetic manual control that is easily accessible from•
the outside on the basis of encoded magnetic fields for
Solenoid Valve 1 (Connection 2/A1), as well as
a mechanical manual control accessible when the hood•
is open on each equipped solenoid valve.
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Structure6.2.
Pneumatic
connections
Locking/(shoulder) screws
as protection against pulling
off from the hub flange
Electrical
connections
(Cable
glands)
Sealing lug
Electronics module
(24VDC- or AS-i-
Design with service
interface, connection
terminals, DIP, Teach-
In-buttons)
Position measuring system with LED’s
Flow restriction
screw(s) of
solenoid valves
Mechanical
manual control
at solenoid
valves (red
levers)
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TECHNICAL DATA7.
Operating Conditions7.1.
Ambient temperature: -10 ... +55 °C
Protection class: IP65 / IP67 according to EN 60529 or
IP69K according to IEC 40050-9
Mechanical Data7.2.
Dimensions: see data sheet
Housing material: outside: PA, PP, PPO, VA
inside: ABS, PA, PMMA
Sealing material: outside: CR, EPDM
inside: EPDM, FKM, NBR
Pneumatic Data7.3.
Control medium: Oil-free and dry air, neutral gases,
Quality classes in accordance with
DIN ISO 8573-1 (5 µm filter
recommended)
Dust content: max. particle size 40 µm,
(quality class 5) max. particle density 10 mg/m3
Water content: max. pressure dew point -20 °C or
(quality class 3) min. 10 °C below the lowest
operating temperature
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Oil content: max. 25 mg/m3
(quality class 5)
Temperature range
of compressed air: -10 to +50 °C
Pressure range: 2.5 to 8 bar
Air rate of solenoid
valve: 110 IN/min (for de-/aeration, ventilation)
(110 IN/min - supplied state
200 IN/min - maximum typical flow-rate)
(QNn value according to definition for
pressure drop from 7 to 6 bar absolute
at +20 °C)
Connections: Intake and exhaust air connection G1/4
Working connections G1/8
Position Measuring System Data7.4.
Stroke range: 0 ... 80 mm (measuring range)
Resolution: 0.1 mm
Total fault: ± 0.5 mm - when using a target as
mentioned in the manual
Electrical Data7.5.
see chapter 9. 24 V DC - Design or 10. AS-I - Design or
11. DeviceNet- Design or 12. 120 V AC - Design.
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ASSEMBLY / INSTALLATION8.
DANGER!
Risk of injury from high pressure in the equipment!
Before loosening pneumatic lines and valves, turn off• the pressure and vent the lines.
WARNING!
Risk of injury due to electrical shock!
Before reaching into the system (except for the• Teach-In procedure in a non-explosive atmosphere)
switch off the power supply and secure it to prevent
restarting!
Observe applicable accident prevention and safety• regulations for electrical equipment!
Risk of injury from improper installation!
Installation may be carried out by authorized techni-• cians 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.•
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Assembly8.1.
For the installation of the Control Head Type 8681 to a
process valve, you will require a process valve-specific hub
flange as an adapter. The hub flange must be adapted to
the design of the process valve.
Mount the piston rod with the target on the process

valve spindle. Observe reference dimensions!
Fasten the hub flange on the process valve.
During this, observe central alignment and sealing
conditions!
Check the secure fit of the sealing rings (in the upper
and lower grooves).
Mount the control head on the hub flange (seamlessly

360° rotatable).
Secure the control head with the two locking screws
(shoulder screws M5) in the middle grove of the hub
flange (see operating instructions).
Pneumatic Installation8.2.
Connect the required working connections 2/A1 to 2/
A3 (each according to model) with the corresponding
connections on the process valve.
Connect the supply line to supply pressure connection

1/P (2.5 to 8 bar).
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A silencer has already been mounted on the Exhaust
Air Connection (3/R) in the supplied state.
1/P
Supply pressure
connection
3/R
Exhaust air
connection
(Silencer)
2/A3: SV 3 2/A2: SV 2 2/A1: SV 1
2/A1 ... A3 - Working connections - Solenoid valves (SV)
Sealing lugs
at the
housing
The flow restriction screws
R and P of the solenoid valves
(see operating instructions) are
used for setting the air intake and
exhaust for the working connec-
tions (for setting of the control
speed of the process valves).
R
P
open close
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Opening and Closing the8.3.
Housing
Opening:
Loosen plastic self-cutting screws or seal, if housing

has been secured.
Open the plastic hood by turning counterclockwise (all

the way, approx. 1.5 cm).
Closing:
Put the plastic hood on the lower part such that the

inner lugs are positioned over the fastening grooves
and the external sealing lugs are positioned almost over
each other. Press the hood completely over the seal of
the lower part.
Turn the hood by approx. 1.5 cm clockwise (meaning
until the sealing lugs are positioned over each other).
A seal or a hood safeguard using plastic self-cutting
screws is required in the explosion-risk area!
Electrical Installation8.4.
see chapter
9. 24 V DC - Design, 10. AS-I - Design,
11. DeviceNet- Design or 12. 120 V AC - Design.
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9. 24 V DC - DESIGN
Connection options9.1.
left: 1 x M16 x 1,5 cable
gland
for power supply and
signals
left: 1 x M16 x 1,5 cable
gland with multi-pole
connection (M12 plug
according to IEC 61076-
2-101, 12-pole) on a cable
of 8 cm length
right: 1 x M16 x 1,5 cable
gland for external initiator
right: 1 x M16 x 1,5 cable
gland for external initiator
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Electrical Data9.2.
Power supply: 12 ... 28 V DC, residual ripple 10 %
Power consumption:
(standby current): 30 mA at 24 V DC
Solenoid valves:
Power input per max. 0.8 W
solenoid valve: (0.9 W during activation)
Operating mode: Long-term operation (100 %)
Central display of the
switching states: 42 mA with a power supply of
24 V DC per illuminated display;
Outputs/binary
feedback signals: S1 out - S4 out
Design: Normally open contact, PNP output
short-circuit-proof, with self-clocking
short-circuit protection
Switchable
output current: max. 100 mA per feedback signal
Option: Analog feedback signal:
Signal output: S3 out (binary feedback signal
S3out not available)
Type: Current source (4 to 20 mA)
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Input / proximity switches (external initiator: S4 in):
Power supply: Voltage present at control head - 10 %
Current carrying
capacity, sensor
power supply: max. 90 mA;
short-circuit protection
Design: DC 2- and 3-conductor, NO or NC
(factory setting NO), PNP output
Valve control inputs (Y1 - Y3):
Signal level - active: U > 10 V, max. 24 V DC + 10 %
Electrical Installation9.3. (24 VDC)
WARNING!
Risk of injury due to electrical shock!
Before reaching into the system (except for the• Teach-In procedure in a non-explosive atmosphere)
switch off the power supply and secure it to prevent
restarting!
Observe applicable accident prevention and safety• regulations for electrical equipment!
Risk of injury from improper installation!
Installation may be carried out by authorized techni-• cians only and with the appropriate tools!
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Cable glands:
Open the housing.

Assemble connection cables for signals and power
supply as well as for the external initiator.
Insert cables through the respective cable glands into

the interior of the housing.
Secure the wires to the terminal strips according to the
pin assignments depicted in the figure.
Solenoid valve
connection
with status
LED for SV1
Terminal strip 1
Service
interface
DIP switches
for color
coding the
LED‘s
Terminal strip 2
(for external
initiator)
Teach-In-
buttons T1-3
SV-connections
with status LED
for SV2, 3
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Terminal strip 1 Configuration
24 V Power supply 24 V
GND GND
S1 OUT Output position 1
S2 OUT Output position 2
S3 OUT Output position 3
(Option: analog signal)
S4 OUT Output external initiator
Y1 Input solenoid valve 1
Y2 Input solenoid valve 2
Y3 Input solenoid valve 3
Terminal strip 2 Configuration
24 V Power supply 24 V for external
initiator
S4 IN Input external initiator
GND GND external initiator
Close the housing
.
Ensure IP protection(dummy plugs)!
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Cable gland with Multi-pole connection:
Internal cabling work is not required for models with multi-pole
connection. But you will require the correspondingly
assembled cable sets with the following pin assignments:
Pin Description Configuration
1 24 V Power supply 24 V
2 GND GND
3 S1 OUT Output position 1
4 S2 OUT Output position 2
5 S3 OUT Output position 3
(Option: analog signal)
6 S4 OUT Output external initiator
7 Y1 Input solenoid valve 1
8 Y2 Input solenoid valve 2
9 Y3 Input solenoid valve 3
10-12 not used
An external initiator can be connected using the small 3-pin
terminal strip 2 (see figure on page 22 or manual, chapter
„Connection of an external initiator“).
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Input and output signals to the higher-level control (PLC):
Pin 9 - Y3
Pin 8 - Y2
12
Pin 6 - S4 out
Pin 7 - Y1
Pin 1 - 24 V
Pin 5 - S3 out
Pin 4 - S2 out
11
Pin 3 - S1 out Pin 2 - GND
10
(12-pole circular plug-in connector M12 x 0.75 - male,
acc. to IEC 61076-2-101 — view onto the plug pins)
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10. AS-I - DESIGN
Connection options10.1.
left connection:
1 x M16 x 1,5 cable gland with Multi-pole connection
(M12 plug according to IEC 61076-2-101, 4-pole) on a
cable of 8 or 80 cm length
right connection:
1 x M16 x 1,5 cable gland for external initiator
Maximum Length of the Bus10.2.
Line
The bus cable may be a maximum of 100 m long. When
designing the system, consider the length of the round cable
leading directly to the control head (see example calculation
in the operating instructions).
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Number of Connectable10.3.
Control Heads
In AS interface versions with extended addressing range
(A/B slave), 1 master can communicate with 62 slaves.
In AS interface versions with addressing range 31 slaves a
maximum of 31 control heads can be connected to a bus line
(the address range restriction).
10.4. Electrical Data
Power supply:
Standard: via AS-i
(29,5 ... 31,6 V DC
acc. specification)
Option: externally
(19,2 V DC to 31,6 V DC)
Setting the valve’s power supply using jumpers on the
AS-interface electronics module.
Input / proximity switches (external initiator: S4 in):
Power supply: AS interface voltage present at
control head - 10 %
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Current carrying capacity,
sensor power supply: max. 30 mA;
short-circuit protection
Design: DC 2- and 3-conductor, NO or
NC (factory setting NO), PNP
output
Inputs (from master
perspective):3 binary feedback signals and
external initiator
Outputs (from master
perspective): 0 to 3 solenoid valves
Switching capacity: max. 0.8 W via AS interface
Pull-in current: 30 mA or 0.9 W / 200 ms
Operating mode: Long-term operation (100 %)
Central display of the switching states:
Power consumption: max. 33 mA or 1 W per illumi-
nated display (at 30.5 V AS-
interface voltage)
Power supply via AS interface bus:
Power consumption
from AS interface: max. 200 mA (incl. external
initiator with 30 mA)
Integrated short-circuit protection
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External Power Supply:
Ext. power supply: 19.2 V DC to 31.6 V DC
Max. power consumption
from external power supply: 110 mA at 24 V DC
Integrated short-circuit protection
Electrical Installation (AS-i)10.5.
WARNING!
Risk of injury due to electrical shock!
Before reaching into the system (except for the• Teach-In procedure in a non-explosive atmosphere)
switch off the power supply and secure it to prevent
restarting!
Observe applicable accident prevention and safety• regulations for electrical equipment!
Risk of injury from improper installation!
Installation may be carried out by authorized techni-• cians only and with the appropriate tools!
Internal cabling work is not required for any of the AS Interface
designs with multi-pole connection. However, you will require
the correspondingly assembled cable sets with the following
pin assignments.
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Pin 2
Pin 3 Pin 1
Pin 4
Likewise, the jumpers on the electronics module must be set
correspondingly (power supply via AS-i or externally) - see
page 27.
Power supply
Pin
(via AS-i)
Configuration
(externally)
Configuration Color
1 AS-i+ AS-i+ brown
2 not used GND white
3 AS-i- AS-i- blue
4 not used 24 V+ black
An external initiator can be connected using the small
3-pin terminal strip 2 - see manual, chapter „Connection of
an external initiator“.
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11. DEVICENET- DESIGN
Connection11.1.
left connection:
1 x M16 x 1,5 cable gland with Multi-pole connection
(M12 plug according to IEC 61076-2-101, 5-pole) on a
cable of 80 cm length
right connection:
1 x M16 x 1,5 cable gland for external initiator
DeviceNet Specification11.2.
EDS file 8681.EDS
Icons 8681.ICO
Baud rate Factory setting: 125 kBit/s
Address Factory setting: 63
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Process data 2 static input assemblies
(Input: from the control head to the
DeviceNet Master/Scanner)
1 static output assembly
Inputs 3 discrete feedback signals of the posi-
tion measuring system (pos. S1 - S3)
1 discrete feedback signal of the
external initiators (S4)
1 analog position signal in mm
Supply via DeviceNet string
(11 to 25 V DC)
Switch level high signal 5 V
Switch level low signal 1,5 V
Outputs 3 solenoid valves
Power consumption
from the bus: max. 5 W, (3 valves with each 0,8 W)
Length of the Bus line11.3.
The maximum total line length (sum of trunk lines and drop
lines) of a network depends on the baud rate.
The maximum total line length (according to DeviceNet
specification) is for:
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Baud rate Thick Cable Thin Cable
125 500 m 100 m
250 250 m 100 m
500 100 m 100 m
The maximum drop line length is for:
Baud rate Drop Line Sum (in Network)
125 6 m 156 m
250 6 m 78 m
500 6 m 39 m
Electrical Data11.4.
Electrical power supply: 11 to 25 V DC (according to
specification)
Max. power consumption: 200 mA at 24 V DC
Input / proximity switches (external initiator: S4 in):
Power supply: via DeviceNet power
supply - 10 %
Current carrying capacity
sensor power supply: max. 30 mA
Short-circuit protection
Design: DC 2- and 3-conductor,
NO contact, PNP output
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Input current 1 signal: ISensor > 6.5 mA, limited
internally to 10 mA
Input voltage 1 signal: USensor > 10 V
Input current 0 signal: ISensor < 4 mA
Input voltage 0 signal: Usensor< 5 V
Inputs (from master perspective) / binary or analog
feedback signals:
The recovery of the 3 valve positions reported back binarily
or of the analog position signalis described in the manual,
chapter “Position Mesuring System”.
Outputs (from master perspective) / solenoid valves:
max. switching capacity 1.0 W
typ. continuous output 0.8 W
Output reduction integrated via DeviceNet
interface electronics
pull-in current 120 mA typ. / 200 ms
(3 valves)
Holding current 100 mA typ. at 24 V DC
(3 valves)
Operating mode Long-term operation
(100 % operation)
Valve types 6524
Central display of the switching states:
Power consumption from
DeviceNet at 24 V DC 42 mA with 24 V DC power
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supply per illuminated display
shown; Color switching see
in the manual, chapter “LED -
Color Assignments”
Electrical Installation (DVN)11.5.
WARNING!
Risk of injury due to electrical shock!
Before reaching into the system (except for the• Teach-In procedure in a non-explosive atmosphere)
switch off the power supply and secure it to prevent
restarting!
Observe applicable accident prevention and safety• regulations for electrical equipment!
Risk of injury from improper installation!
Installation may be carried out by authorized techni-• cians only and with the appropriate tools!
No internal cabling work is required for any of the Devi-
ceNet designs.
However, you will require the correspondingly assembled
cable sets with the pin assignments described below:
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Pin 4: CAN_H
Pin 5: CAN_L
Pin 1: Drain
Pin 3: V–
Pin 2: V+
View of plug from the front onto the pins:
Pin Signal Color
1 Drain (shield)
2 V+ red
3 V- black
4 CAN_H white
5 CAN_L blue
An external initiator can be
connected using the small
3-pin terminal strip - see
manual, chapter „Connection
of an external initiator“.
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Network Topology11.6.
When installing a DeviceNet system, ensure that the termi-
nating circuit of the data lines is correct. The circuit prevents
the occurrence of interference caused by signals reflected
onto the data lines.
The trunk line must be terminated at both ends with
resistors of 120 Ωand 1/4 W power loss (see the manual,
chapter „Network Topology of a DeviceNet System“).
Configuring the Baud rate11.7.
and DVN address
8 DIP switches are available for configuration:
DIP switches 1 to 6 for DeviceNet address•
(factory setting: 63, i.e. DIP 1 - 6: on)
DIP switches 7 to 8 for Baud rate•
(factory setting: 125, i.e. DIP 7 + 8: off)
Further configuring - see manual, chapter „Configuring the
DeviceNet address / baud rate“
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Configuration of Process Data11.8.
To transmit process data via an I/O connection, 2 static
input and 1 static output assembly can be selected, see
manual, chapter “Configuration of Process Data”
„Address“ in the table describes the data attribute of the
assemblies for read access (class, instance, attributes).
Input-
Assemblies
Address Format of the Data attribute
value 0: OFF / value 1: ON
S1…S4
(factory
setting)
4, 1, 3 Byte 0:
Bit 0: position S1
Bit 1: position S2
Bit 2: position S3
Bit 3: position S4
S1…S4 +
POS
(with POS:
current
position)
4, 2, 3 Byte 0:
Bit 0: position S1
Bit 1: position S2
Bit 2: position S3
Bit 3: position S4
Bit 4…7: not used
Byte 1:
POS in mm
„Address“ in the table describes the data attribute of the
assemblies for read access (class, instance, attributes).
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Output-
Assembly
Address Format of the Data attribute
value 0: OFF / value 1: ON
Solenoid
valve
SV 1 ... 3
4, 21, 3 Byte 0:
Bit 0: SV1
Bit 1: SV2
Bit 2: SV3
Bit 3…7: not used
Configuration of the Safety11.9.
Position of Solenoid Valves if
Bus Error
If the bus fails, the solenoid valve is switched to a program-
mable safety position (factory setting: the solenoid valve
is in the power-off-state) - for details see manual, chapter
„Configuration of the device“.
The bus status LED „Network“ on the electronic module
specifies the kind of error by color and blinking pattern - for
details see manual, chapter „Display of the Status LEDs in
the event of a bus error“).
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