Burkert 8792 - Connection and Start-Up Via a 4 - 20 Ma Position Sensor (for Type 8793 Remote Model Only)

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Installation
Type 8792, 8793
english
12.4.3. Connection and start-up via a 4 – 20 mA position sensor
(for Type 8793 remote model only)
When a 4 – 20 mA position sensor is connected, the process controller Type 8793 can be used as a posi-
tioner only, as the process actual value input is used as input for the position sensor.
In principle, any position sensor with a 4 – 20 mA output can be connected which has an adequate resolution of
the path signal.
Good control properties are obtained if the resolution of the position sensor allows at least 1000 measuring steps
over the path to be measured.
Example: Position sensor with 150 mm measurement range
Of which used measurement range (= stroke) 100 mm
Required minimum resolution of the sensor:
100 mm
= 0.1 mm
1000 Steps
WARNING!
Risk of injury from improper start-up.
▶ Start-up may be carried out by authorised technicians 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.
Connect 4 – 20 mA position sensor to the terminals 1 - 4 of the process controller Type 8793 remote model.
(see chapter “Table 22: Terminal assignments of the process actual value input”, page 56 /
Internal supply of the position sensor by Type 8793:
→ Connection according to input type “4 ... 20 mA - internally supplied”
Separate supply of the position sensor:
→ Connection according to input type “4 ... 20 mA - externally supplied”.
→ Attach remote sensor on the actuator.
The correct procedure is described in the instructions for the position sensor.
→ Connect compressed air to the Type 8793.
→ Connect Type 8793 pneumatically to the actuator
→ Switch on Type 8793 operating voltage.
→ To obtain the best possible control precision, adjust the position sensor so that path to be measured corre-
sponds to the signal range 4 – 20 mA (only if the position sensor includes this function).
→ In the ADD.FUNCTION menu activate the POS.SENSOR function. Then select POS.SENSOR in the main
menu and set ANALOG.
(see chapter “26.2.19. POS.SENSOR – Setting interface remote position sensor”, page 137.
→ Run the X.TUNE function.