Burkert Type 8681 - Manual (Page 17)

17
System Description
position Measuring system 5.4.6.
The switching positions of the process valves are reported to the higher-level control by feedback signals from
the contactless position measuring system. Connection to the control head is done by means of a simple adap-
tation to the process valve's piston.
The recordable stroke range is between 0 and 80 mm.
Three binary feedback signals are evaluated:
- Position 1 (discrete S1OUT signal)
- Position 2 (discrete S2OUT signal)
- Position 3 (discrete S3OUT signal).
The 24 V DC design is additionally available in the order variant "Analog":
Order variant:
- Position 1 (discrete S1OUT signal)
- Position 2 (discrete S2OUT signal)
- Position 3 (analog (4...20 ma) S3OUT signal).
Three Teach-In buttons have been provided for comparison with the actual stroke range (see chapter 15. Position
Measuring System). The switching positions for the position measuring system can be determined with these
buttons or by means of the service interface (on the electronics module).
An discrete, external feedback signal (standard proximity switch) can also be processed (S4IN, S4OUT).
if an explosive atmosphere is present the housing may not be opened when voltage is present.
For a detailed description of the electrical installation, see chapter 10. 24 V DC - Design or
chapter 11. AS Interface - Design.
For the setting of the Teach-In buttons, see chapter 15. Position Measuring System.
Other features 5.4.7.
Central optical position indicator for showing the process valve switching positions: •
Positions and status information can be indicated by means of three signal colors.
The assignment of the signal colors and the blinking pattern, which indicates the type of fault, are described in
chapter
16. LED - Color Assignments.
Simple adaptation of the control head (for the position measuring system) to the process valve piston rod •
Simple adjustment of the position measuring system by three Teach-In buttons on the electronics module •
The capability of restricting the pilot valve (solenoid valve) for the individual setting of the expansion and •
retraction rates of the process valve and the individual setting of the flow-rate of the working connections
More energy efficient solenoid valve control by lowering the holding current during long-term operation •
english
Control Head Type 8681