Page 231 - Bürkert

Control- and feedback head for integrated mounting on
Robolux valves Type 2036

8685 / 8686 • Compact stainless steel design

• Contactless valve position registration
• Fieldbus AS- Interface (optional)
• Version for NAMUR circuits (optional)
Type 8686

Type 8685

Feedback, Type 8685, and control head, Type 8686, are optimised for Dimensions [mm] (see datasheet for more details)
integrated mounting on pneumatically operated actuator, Type 2036
Robolux. The adjustment to the individual actuator size is done through Type 8685 C
DIP-switches.
As a compact unit the devices provide the complete automation function- A B C
ality for the two individually operated actuator pistons. 90.8 86.2 55.8
Depending on the configuration the electrical and visual position feed-
back is done by non-contact switches and high-power LEDs. Integrated
pilot valves control the actuator pistons and AS-interface communication
B
is available. Using appropriate barriers both types feature intrinsic safety
acc. to ATEX.
In this way a complete concept for decentralized automation is feasible A
for the process technique.
The compact body is especially distinguished by its hygienic design, with
resistance to cleaning agents and a proven electrical IP protection. C
In addition the control head, Type 8686, features an integrated com- Type 8686
pressed air filter to protect the pilot valve function against particles
A B C
through the compressed air supply. 90.8 115.4 50.3

Technical data B
Material:
Body PPS, stainless steel
Cover PC
Seal EPDM
Power supply
Limit switches 24V DC +/- 10%
8.2V DC (Ex-i-NAMUR switch amplifier)
U < 12V, Ii < 20 mA, Pi < 60 mW (Ex- Barrier)
Pilot valve 24V DC +/- 10% A
max. voltage see note
2)
Pilot valve Residual ripple 10%; Power consumption 0.8 W every
valve for Ex i-variants: acc datasheet II 2G Ex ia IIC Technical data (cont.)
T4 T5 T6 PTB01 ATEX 2048
Control medium Neutral gases, air DIN ISO 8573-1 Ambient temperature 0 ºC to +55 ºC
Dust content Class 5 (<40 µm particle size) Installation As required, preferably with actuator in upright position
Particle density Class 5 (<10 mg/m ) 3 Type of protection IP65/67 according to EN 60529
Pressure dew point Class 3 (<-20 °C) Protection class 3 acc. to VDE 0580
Oil concentration Class 5 (<25 mg/ m ) 3
Supply pressure 3-7 bar 1) Fieldbus communica- AS-Interface
tion
Air supply filter Exchangeable CE acc. to EMV2004/108/EG
Mesh aperture ~0.1 mm Conformity
Electrical connection
Pilot air ports Threaded ports G 1/8”
Multipole M12 (8-pin), M12 (4-pin) with 1 m cable (AS-Interface)
Position feedback Reed sensors (no contact) Cable gland M16x1.5 (Cable Ø 6.5 mm), screw terminals (1.0 mm 2 )
Stroke range valve RV50 = 6.0 mm, RV70 = 9.5 mm, RV110 = 13.5 mm 1) The supply pressure must be 0.5 to 1 bar above the minimum required control pressure of
spindle
the valve actuator.

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