Help with Measuring Load Cell Voltage

Shouldnt be too hard, only problem is that the loadcells can out out up to 8.8v... too high for the Analog pins i think. How can I turn the 8.8v into 5v? Resistor? I would prefer not to have to completely redesign the load cell setup to run on 5v :slight_smile:

Ryan

rpmaurer:
Shouldnt be too hard, only problem is that the loadcells can out out up to 8.8v... too high for the Analog pins i think. How can I turn the 8.8v into 5v? Resistor? I would prefer not to have to completely redesign the load cell setup to run on 5v :slight_smile:

Ryan

Can you provide a link to your load cell device? Most we see are very low voltage output devices, millivolt outputs usually requiring a op-amp to interface usefully to an arduino. So any advice we could give should be in context with a datasheet based on your specific load cell.

If indeed your device outputs a 0 to +8.8vdc measurement signal, a simple two resistor voltage divider using a divide by 2 ratio (two 5k ohm resistors in series should work fine) would work easily for an arduino analog input pin.

Lefty

Listen to Lefty he is making good sense, pat manufactures and numbers and a schematic would help,

It is an Aerocon Load Cell, used for Testing rocket motors with forces of up to 220lb. And yes it does output in millivolts, my amplifier that I made hoever puts it up to 8.8v

For load cells I have good luck with simple instrumentation amps like TI's INA122's powered off the 5 V line from Arduino, the output on it is 0 - 5V. In your case I would check if you can operate your amp with a lower voltage so your output does not exceed 5 V. Alternatively, you could probably use a simple voltage divider with two resistors.

rpmaurer:
It is an Aerocon Load Cell, used for Testing rocket motors with forces of up to 220lb. And yes it does output in millivolts, my amplifier that I made hoever puts it up to 8.8v

Can we have links to datasheets for both the load cell and the amplifier please?