VEGA VEGAFLEX 86 4 … 20 mA_HART two-wire Rod and cable probe With SIL qualification User Manual

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7 Set up with the display and adjustment module

VEGAFLEX 86 • 4 … 20 mA/HART two-wire

44234-EN-130823

In this case, you have to carry out a function test.
Function test

During a function test, you have to test the safety function of the

instrument in the vessel with the original medium.
For this purpose, you should know the filling height of the vessel as

well as the min. and max. levels respectively for 4 and 20 mA. You

then can calculate the respective output current.
Measure the output current of VEGAFLEX 86 with a suitable multi-

meter and compare the measured output current with the calculated

output current.
You have to determine the permissible deviation of the values

yourself. This deviation depends on the the accuracy requirements of

your measurement loop. Determine the permissible tolerance for the

deviation.
If you have to interrupt the function, you can leave the VEGAFLEX 86

in the respective situation.
As long as VEGAFLEX 86 is powered, the display and adjustment

module remains in the currently set adjustment menu.
To interrupt the function test, you have to push the button "ESC".
If you carry out the function test by means of the "PACTware" soft-

ware, you can store the previously performed tests and continue from

there later on.
Verify parameter

All safety-relevant parameters must be verified after a change. After

the function test, all modified, safety-relevant parameters will be

listed. Confirm the modified values one after the other.

If the described process of parameter adjustment was run through

completely and correctly, the instrument will be locked and hence

ready for operation.

Otherwise the instrument remains in the released and hence unsafe

condition.
If you have to interrupt the function test, you can leave the display and

adjustment module of VEGAFLEX 86 in its current state.
As long as VEGAFLEX 86 is powered, the display and adjustment

module remains in the currently set adjustment menu.