We have to construct a weight board. This can be wooden or metallic.
If you are going to use a 1Kg load cell wood might be better, but for a 20Kg load cell you should use metal.
As you can see we need two surfaces, two wedges, four screws and the load cell in the middle.
Remember that the load cell works only at one side. You have to find the working side yourself.
Below you can see both 1Kg and 20 Kg weight boards.
The two surfaces (up and down) can be from 10x10cm up to 24x24cm. The metal surfaces have 2mm of thickness.
The trick here is to construct the board starting from your load cell.
The holes of the load cell will determine where your screws should be placed.
Notice that the blue wire can be the green one sometimes.
Use a 4-pin male array header. The four wires should have a max of 1 meter of length.
At this point we are ready to calibrate our liquid filler.
Remember that the code provided at the part 2 give us the average analog read and not any gram information . (A 0-1023 value).
In the next tutorial, with the help of scidavis, we will transform the analog readings in grams.
Our liquid filler will fill up bottles and containers in general with the help of gravity. So no pump is required.
We are going to use a gravity feed valve 12 VDC that will be connected on the male pins of the board.
The valve does not have a current direction but has a flow direction.
Pay attention at this detail.
That's all for now.