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By school_kid_23
#207643
Hi guys, I'm making an automatic pet feeder that has a weight sensor. I've had to order my parts twice. I originally just bought the load sensor then found out I had to buy a module also, (HX711 module to be precise.) I've been looking at how to make scales and see that most projects have a load cell and not a load sensor, which is what I think I have.Image Could I still make my prject work or will I have to order a load cell, which looks like a rectangle metal bar.
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By TS-Chris
#207678
Hi school_kid.

What sensor do you have now? I didn't see a picture attached to your post. We carry a three wire load sensor and if you have that, you'd need a total of 2 or 4* of them to connect them to the HX711.
* It's possible to do it with one three wire sensor, but is more difficult.

The square load cells we carry should work well for a project like this and would connect directly to the HX711 with no issues. I don't know what parts you're using, but you'd need at a minimum the following parts:
  1. One load cell (4 wires) or several load sensors. (3 wires) A 4 wire load cell is going to be easier to use than one or more 3 wire load sensors.
  2. The HX711 load cell amplifier.
  3. A micro-controller to read data from the HX711
I'd suggest having a look at the hookup guide for the HX711 as that will walk you through how to connect everything together and the guide also has some sample code to get you started.