Ok I am running into a new issue , I am getting a MAX output of 1.7vdc out of the analog outs using a 2 ton load cell , I have 1 ton of force on it and it max;s out at 1.7vdc, I tried a 5ton load cell and I get the same thing , I have the small pot all the way clockwise , if I put it anywhere else it just offsets the voltage and then I have a input error , is there any way to use full range on this thing ? my load cells are 2mv/volt sensitivity. I am using a hydraulic force gauge to measure actual force my max is 2000 lbs or 1 ton.
Note: may be related to this topic.
Hi,
The load cell excitation voltage might be the cause of this issue. By default, when you stack the Wheatstone Bridge Shield on an Arduino board, the load cell gets its excitation voltage from the Arduino 3.3V pin. You might want to try to power the load cell with a 5V instead. To do this, you can slightly bend the Wheatstone Bridge Shield 3.3V pin and connect it (using a M/F jumper cable) to the Arduino 5V pin (through the Wheatstone Bridge Shield 5V header pin)
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Thats what I was thinking , all the chips will take 36 vdc max ,I did bend the 3.3v pin out of the way and I still had 3.3v ex. voltage to the load cell , I really need to know how the supply is distributed , HEY ROBOTSHOP WHATS the deal here ???
ok well I bent the wrong pin ! gonna try it again,.
Ok I lifted the 3.3v pin and connected it to the 5v pin and now I have 3.0 volts of range ! so IF you need to increase the range try this , all the chips will handle up to 36v PS MAX from the data sheets.
keep in mind that MAX output voltage vs. Max input on your Arduino board !!! If you run this standalone you can go to much higher voltages out
The MCP602 ICs are also powered through the 3.3V Arduino pin on the Wheatstone Bridge Shield. These chips are rated for a maximum 6V as indicated in the datasheet. Therefore, the maximum voltage that you can put on the Wheatstone Bridge Shield 3.3V pin would be 6V and not 36V
good point seeing there is no schematic there is no way I would know
