VEGA VEGAFLEX 83 4 … 20 mA_HART two-wire Rod and cable probe - PFA insulated With SIL qualification User Manual

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6 Functional safety (SIL)

VEGAFLEX 83 • 4 … 20 mA/HART two-wire

44228-EN-130823

Setup is then finished.
Function test required

Should a function test be necessary, the following message is

displayed on the display and adjustment module. The adjustment

software also signals that a function test is required.

If a function test is required, the switching point or the range must

be controlled with the original medium. For this purpose, you have to

decide for your application which condition is potentially critical.

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 83 with a suitable multi-

meter and compare the measured output current with the calculated

output current.
If you have to interrupt the function, you can leave the VEGAFLEX 83

in the respective situation.
As long as VEGAFLEX 83 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.
If you click to "Complete", the adjustment of the instrument is locked,

but not yet verified. After conclusion of the function test, you have to

restart the adjustment.
If a function test is necessary, please proceed as follows:
Mode overfill protection/dry run protection

Select the respective safety function (overfill protection/dry run pro-

tection) for your application.
1. Raise the level to directly below the switching point

Keep a holding time of 1 minute for each level before you com-

pare the measured value.

2. Lower the level to directly above the switching point

Keep a holding time of 1 minute for each level before you com-

pare the measured value.

Result
In both cases the output current must correspond to the respective

level.

Function test