Hi.
Im making a proyecto of a scale but im having issues deciding what components should I use.
I need to make a scale that works on a temperature of 95 farenheit (36° celsious) and that work during 8 hours per day.
Im thinking of using a load cell of 5 kg, but I dont know what component to use for the scale give me a acuracy of 0.001 kilograms, and what kind of battery should I use so that I can work for such that time without any inconvinience.
I’d suggest a look at commercial scales to see if they can meet your specification first - it looks a bit tight to get such accuracy at high temperatures, useful to know how “ doable “ this task is before you try and build one .
I have a cheap scale here that's doing 0.1 gram resolution on a full scale of 250 gram. That's 1:2500. My experience is that it's pretty accurate, and this kind of resolution is definitely not lab grade. I paid something like USD 25 or so for it, not sure, it's been over a decade ago. Still works fine.
Now if you're talking about a scale that can do 250 gram at 0.0001 gram precision... or 1:2.5M... then you're looking at lab grade! Those scales are usually placed on big chunks of stone to help keeping vibrations out (from people walking by over a solid concrete floor).
1 gram resolution on a 5kg load cell should be no problem, as long as the load cell itself is up to it. The rated precision of the load cell linked to by OP is 0.05%, that's 2.5g error, making it unsuitable for this application. OP will need a better load cell, one that's accurate down to 50 ppm (0.005%).
There is a big difference between accuracy and resolution , and how accuracy may change with temperature.
If a cheap scale will do your job , then use it .
Why do you need such accuracy/resolution - what is the task ?
Bear in mind that if the scale is used for measurement and selling it will need to be approved and have traceable calibration
