3 level measurement – VEGA VEGADIF 65 Foundation Fieldbus User Manual

Page 59

8 Setup

VEGADIF 65 • Foundation Fieldbus

36130-EN-130417

For this purpose, open valves A, B (if available) as well as 2, 4:

Medium flows in
If necessary, clean the differential pressure lines: - with gases by

blowing out with compressed air - with liquids by rinsing.

For this purpose close valve 2 and 4, i.e. block the instrument.
Then open valve 1 and 5 so that the effective pressure lines blow

out/rinse.
Close valves 1 and 5 (if available) after cleaning

3. Remove air from instrument:

Open valves 2 and 4: Medium flows in
Close valve 4: Minus side is closed
Open valve 3: Equalisation plus and minus side
Briefly open valve 6 and 7, then close again: Fill the measuring

instrument completely with the medium and remove air

4. Carry out a position correction if the following conditions apply. If

the conditions are not fulfilled, then carry out the position correc-

tion after step 6.
Conditions:
The process cannot be sealed off.
The pressure extraction points (A and B) are at the same geo-

desic height.

5. Put measurement loop into operation:

Close valve 3: Separate plus and minus side
Open valve 4: Connect minus side
Now:
Valves 1, 3, 5, 6 and 7 are closed

Valves 2 and 4 are open
Valves A and B open

6. Carry out position correction, if flow can be blocked. In this case,

step 5 is not required.

Then carry out adjustment, see chapter "Set parameters".

8.3 Level measurement

For level measurements, all versions of VEGADIF 65 are employed.
VEGADIF 65 with double chemical seal is immediately ready for

operation.
The VEGADIF 65 without chemical seal or with single chemical seal

is ready for operation after opening a blocking valve, in case one is

present.
Before you adjust VEGADIF 65 without chemical seal or with single

chemical seal, the effective pressure lines must be cleaned and the

instrument filled with the medium.

Instructions

Arrangement with 5 valves.

Valves 1, 3, 5: Configuration with 5 valves.