Some small details about the pressure transmitter before we begin. The pressure transmitter outputs data between 4-20mA, which gives a number which you then need to convert to get the pressure in relation to the height of the container.
So, where should the formula be and what is the formula?
There are two different places where you can enter the formula. The first place is under the device itself, where you can change the data input and enter a formula.
The other place is in the equation node itself - you just get to see it inside your flow. There's really no difference between these two, except that they are in different places and require one or no extra node.
In this post, I will start by setting up the formula in the unit itself. While I simulate the value through a value node.
( x - 200 ) * height in metres / 7999
However, if you want it in centimetres, you need to add 2 extra zeros to the height, e.g. 5 metres to 500 centimetres.
Boilerplate Flow
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