I try to use the load cell 3140-500kg with arduino uno.Because the signal of the load cell is too low is connect the INA114 amplifier to level up the signal.I build the schematic shown in the image.
WIth the multimeter I get a signal of 2.36V for 0 load and when I press the load cell it goes down.At full load I get 0V.
The problem is that i send that signal to arduino A0,I write down just a simple sketch just to get tha signal but what I get is non stable numbers like 860 and 138.(4-5 times it gives me 860-865, then few times 142-138).Besides the signal dont change at all even that in multimeter all seems fine...
Could someone help or give me an idea?
Did you use different power sources or do you use the same for Arduino and load cell (e.g. through Vin)? If not: Did you connect both GNDs?
This should help
http://forum.arduino.cc/index.php?topic=155767.0
Ray
THANKS!!!!!!!!!
What was the solution to your problem, data smoothing or ground connection? So other can learn too.
FInally i connected my load cell to arduino 5V power supply all seems to work fine,I get a signal around 2.5V.Probally the problem was the 12V power supply to the load cell and a kind of comflexion with ground.Now I am working on smoothing and to create a gui with proccesing 2.0.I hope ill have something good to show soon!!!