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Author Topic: Load Cell Help  (Read 402 times)
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I have four load cells taken from a digital bathroom scale with three wires (red, white, black) and have read over the similar forum posts about how to hook them up. I am supplying a voltage with the red and black wires and am reading the voltage drop with the white and the black wire connected to the voltmeter just like the others have done. Problem is I am not seeing a voltage change on the voltmeter when I push on the load cell--I just see the same voltage across the white wire as I am supplying with the voltmeter.

I have tried a few of the four load cells so it is not a bad load cell.
I have made sure I am pushing hard enough to bend the cell.
I have tried a range from 3-5V (not sure why it would make any difference but tried it anyway).

I don't understand. Any suggestions?

McKinnley
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I don't understand. Any suggestions?

raw loads cells output just a few millivolts over their full range, 0-10mv maybe. Are you sure your meter has a sensitive enough range to measure such low dc voltage? Most load cell applications require an external op-amp to raise the cell's output voltage range to a more useable range for measurement.

Lefty


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