Testing wheatstone bridge/load cell amplifier shield

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I was performing the quality test for the robotshop wheatstone bridge/load cell amplifier shield for the arduino uno. In step 6, I was reading a value of ~655 on both strain 1 and 2 when the test procedure calls for an acceptable range of 665 - 675. It also says that since the excitation voltage may be a bit lower than 3.3 V DC, the final output may be lower. I plugged the arduino into a USB 3.0 port on my laptop and my laptop was plugged in. Is the 655 output I was reading acceptable for the shield or is considered defective? When performing step 7, I was able to achieve values ~0 for both strain 1 and 2.

Here is the test procedure I used for reference: https://www.robotshop.com/media/files/pdf2/load_cell_shield_test-procedure.pdf

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Hey @e4lau,

Welcome to the RobotShop community!

Yes, that is completely fine. You can adjust the potentiometer a bit to shift the value upwards (towards 665-675) if needed.
At worst case, you’d only lose < 1% of the full 1024 value range (~10 points), which is still more than enough left to get proper values.

Have you tried running some of the example code with a load cell connected and see if you get good values when in use?

Sincerely,

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