Product Description
Control head for decentralised automation of ELEMENT process valves
The device Type 8691 control head is designed for decentralised automation of ELEMENT Type 21xx pneumatic process valves. The valve position is registered via a contact-free, analogue sensor element which automatically detects and saves the valve end position using the Teach function during start-up. The integrated pilot valve controls single or double-acting actuators. An optional communication interface, AS-Interface, IO-Link or büS (based on CANopen) can be selected. The design of the control head and the actuator permits integrated pilot air duct without external piping. Besides the electrical position feedback, the device status is shown directly on the control head itself through coloured powerful LEDs, even in difficult ambient conditions. The housing is easy to clean and features proven IP protection and chemically resistant materials for use in hygienic processing in the food, beverage and pharmaceutical industries. Focused on plant wash-down applications, the IP protection of the housing is supported by positive pressure inside the control head. Combined with Buerkert ELEMENT actuators, the pneumatic actuating system enables spring chamber aeration that avoids actuator chamber contamination from the environment.
Technical data
Device & function (8)
| Type |
8691 |
| Product sub-group |
Control head / position feedback |
| Function |
Control head |
| Manual override |
Yes |
| Position sensor type |
internal linear |
| Suitable for actuator sizes |
70, 90, 130 mm |
| Generation |
Revision 3 |
| Installation type |
ELEMENT - actuator |
End position feedback (4)
| End position feedback internal |
2 PCE |
| End position feedback external |
0 PCE |
| End position feedback top |
yellow |
| End position feedback bottom |
green |
Pneumatics (4)
| Pneumatic function 1 double-acting |
No |
| Pneumatic function 1 single-acting |
Yes |
| Valve orifice size |
3 mm |
| QNn value (gas) |
250 l/min |
Pneumatic connections (3)
| Port connection 1 type |
Internal thread |
| Port connection 1 thread type |
G |
| Port connection 1 thread marking |
1/8 |
Communication & electrical (12)
| Electrical connection type |
Plug - M12 |
| Electrical connection type |
male |
| Electrical connection material |
Stainless steel |
| Voltage min / nominal voltage |
29,5 V |
| Voltage max / nominal voltage |
31,6 V |
| Supply voltage system-internal |
No |
| Supply voltage via BUS |
Yes |
| Supply voltage via isolated barrier |
No |
| Galvanically separated actuator supply |
No |
| AC voltage |
No |
| DC voltage |
Yes |
| Communication interface protocol |
ASi + Service-büS |
Temperature & protection (3)
| Environment temperature min |
-10 °C |
| Environment temperature max |
55 °C |
| Degree of protection IP (max. with suitable connection) |
IP65/67 |
Approvals (2)
| Approval type |
ATEX, Ex national, IECEx |
| Certification type |
II 3 D Ex tc IIIC T135°C Dc, Ex ec IIC T4 Gc, Ex tc IIIC T135°C Dc, II 3 G Ex ec IIC T4 Gc, China (CCC) |
Shipping & customs (4)
| Weight |
0,550 kg |
| Customs tariff number |
90268020 |
| Country of origin |
Germany |
| Export |
Not subject to export licensing |
Product benefits
- Contact-free inductive valve position registration (Teach function)
- Colour illuminated status display
- Integrated pilot air duct in the actuator
- Fieldbus interface AS-Interface, IO-Link or Buerkert system bus (büS)
- With ATEX II cat. 3G/D / IECEx approval
Your Benefits With Us
- Worldwide shipping of all valves and flow meters
- Large stock levels for many products – current lead time available on request
- Spare parts and service kits available
- Fast shipping via UPS (parcel) or freight forwarder (pallets), express delivery available on request
- Extensive hands-on application know-how
- Personal advice on selecting the right component
- Resellers receive volume-based discounts on request
- Large companies, public authorities and government agencies can order on account (request via our contact form)
