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Member Since: January 22, 2011

Country: United States

  • Doesn't work that way. You need an extra single axis gyro on the z-axis for that to work. Try one of the 6 DOF boards.

  • I was wondering if someone could give me a desrciption of what each connection point is and does.


  • Well, you're not going to be able to just "write code" for a load cell. If you've looked over all of the posts above, you'll notice that there is some ciruitry involved in just getting usable data from the load cells. Then you need to decide how to send that data (over network, serially, etc.). Once into your PC, and I'm no expert on writing Web apps, I would guess that you need to write an app in C++ or VB.net or some other language to get that data into something that your Web app can use. There is a bunch of stuff involved in this process. Hopefully I didn't make it seem impossible, I just want you to know what is involved. See my site at www.kegmonitor.webs.com to see what I have done. Not too far off of what you want.

  • Go to my scale design site at www.kegmonitor.webs.com. I used silicone to attatch to a steel plate. It holds well, is waterproof, and should not affect the results much, if any.

  • For best results, after a bunch of experimentation, send -5VDC to pin 4 of your IA (AD620) and make sure to ground REF (Pin 5) to a common ground. I have four sensors, leads encased in shrink wrap except for about an inch at the ends, connected to 2 AD620's, 2 per AD620. One sensor has its white as positive and one has black as positive. This is for each IA. The red of the sensor with its white to positive goes to pin 2 (-) of the IA for each sensor. The other red to pin 3 (+). Readings with my Arduino Uno are promising for a working scale. Also have a VB.Net program for display on the PC.

  • Would I use the two inputs on an AD620, or would I use 2 of the chips, grounding one of the inputs on each chip and running those outputs into an ADC and adding the results?

  • I built the circuit using 2 load cells and a AD620 instrumentation amp. Works as advertised. One cell increases the voltage, the other decreases it. What if I wanted to make a scale with four points? Would I need eight cells connected to four AD620's with four cells just sitting there doing nothing, or is there a better way to get usable values from just four cells?

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