Public:Vegabar Vegabar86 Pressure Transmitter Coater

1 Overview

The Vegabar86 is a 2-wire, 4-20mA pressure transmitter used for level measurement in coater mass supply tanks.

2 Basics

Usually there is a small and a big tank connected together. The big tank is used to "calm down" the liquid and to reduce foam. The coating liquid is pumped from the small tank into the coating chamber and returns to the big tank.

First thing is to get the proper dimensions of the tank.

In this example we have a small tank with approx. 40cm diameter and 29cm height > approx. 36liters. The big tank has a diameter of 69cm and of course we cannot fill it up more than 29 cm, since the two tanks are connected. So we calculate the volume of the big tank with 108 liters. So both tanks togehter have 144 liters.

This is what wee want to read when the tank is filled up to 29cm. Why do we want to read both tanks? Because they are connected and the sensors reads the pressure of the liquid - and this pressure is for both tanks.

3 Parametrization

Now that we have established the basics, we can go and parametrize the Vegabar sensor.

To do this properly the tank has to be filled up with the coating liquid.

The following is an example done with water - if you have experience how the value will differ with coating liquid, please add to this article.

Navigate with the four buttons on the sensor display "OK", ">" and "+".

Press "OK", move with ">" to "Extended adjustment" > "OK".

Enter menu "additional adjustments".

Enter menu "scaling".

Set als "scaling variable" >> "Pressure".

Set the unit to "bar"

Go to "scaling format"

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Set the format (decimal point) to "#.####"

Now we need to know what pressure on bar the sensor was displaying with the full tank.

With water the display was 0.0236bar. We want to use the full resolution of the sensor and give a little space on the top.

So adjust the scaling to 0.0250 bar for 100%.

Leave scaling for 0% at 0.0000bar.

Now we need to setup the current output accordingly.

We want to have 4mA at 0% and 20mA at 100%.

So navigate to "Current Output".

Select the "Current output variable"

Of course this is also "Pressure" here:

Select "current output, adjustment".

Do the same as for the sensor scaling before. We want to scale the 100% output to 0.0250 and 0% to 0.000.

Now in WinCC no magic necessary. Set the FacMul to whatever we have calculated for the volume (144 Liters) and FacDiv to the usual 27648.