Burkert Type 8681 - Manual (Page 67)

67
Position Measuring System
15. pOsiTiOn Measuring sysTeM
The switching positions of the process valve 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 adaptation
to the process valve's piston.
The recordable stroke range is between 0 and 80 mm.
Three binary feedback signals are evaluated:
- Position 1 (a discrete S1OUT signal)
- Position 2 (a discrete S2OUT signal)
- Position 3 (a discrete S3OUT signal).
The 24 V DC design is also in the ordering option "Analog" available:
- Position 1 (a discrete S1OUT signal)
- Position 2 (a discrete S2OUT signal)
- Position 3 (an analog (4...20 ma) S3OUT signal).
Three Teach-In buttons have been provided for comparison with the actual stroke range. 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).
A discrete, external feedback signal (standard proximity switch) can also be processed (S4IN, S4OUT).
s 15.1. etting the position Measuring system (Teach-in)
Danger!
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 atmosphere is only allowed in the isolated state! •
example procedure (for three valve positions):
Open the housing observing the notes contained in chapter
→
8. Opening and Closing the Housing.
Supply electrical power so that the position measuring system and the LED display can function.
→
Position the process valve at the lower switching position.
→
Depress the lower Teach-In button (T1) for approx. 1.5 seconds:
→
The LED corresponding to this position will flash quickly three times during the teaching phase.
Once this position has been stored, the corresponding LED will remain continuously lit until the position of the
piston is changed.
Afterwards, position the process valve at the upper switching position to be recorded.
→
Depress the upper Teach-In button (T2) for approx. 1.5 seconds:
→
The LED corresponding to this position will flash quickly three times during the teaching phase.
Once this position has been stored, the corresponding LED will remain continuously lit until the position of the
piston is changed.
The process valve can now be moved into a third, defined position.
→
Depress the middle Teach-In button (T3) for approx. 1.5 seconds:
→
The LED corresponding to this position will flash quickly three times during the teaching phase.
Once this position has been stored, the corresponding LED will flash continuously until the position of the
piston is changed.
english
Control Head Type 8681