Strain Gague Use on HX711

Sensors Force & Weight
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I have a[https://www.digikey.com/product-detail/ … ND/7344715] 2-wire strain gauge that I’d like to get measurements from and understand that an HX711 Amplifier might be useful, however, the information indicates it needs a 4 wire load cell consisting of a wheatstone bridge…

  1. Can I hook up one of the 2-wire strain gauges to the HX711 and get fairly accurate readings?

  2. Is the use of the combinatory the way to ass more strain gauges or can the HX711 handle more of the 2-wire verions?

Thanks.

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Hi Roberts77, and thanks for using the new forums!

  1. Can I hook up one of the 2-wire strain gauges to the HX711 and get fairly accurate readings?
You can, but you need additional parts to make it work. The HX711 is expecting to see a sensor(s) connected in a [[Wheatstone bridge](https://en.wikipedia.org/wiki/Wheatstone_bridge) configuration on the input. Usually there are four resistors in a bridge, your 2 wire sensor being one of those resistors. What you're probably going to want to do is figure out what the resistance is on your particular strain gauge and then order three 1% or better resistors of the same resistance and connect everything in a bridge configuration. The connections at the top and bottom of your bridge would be the excite connections (*Red / Black or E+ and E-*) and the connections on the left and right hand side would be your sense connections. (*Green / White or S+ and S-*) Below is a picture that might explain this better.

Wheatstonebridge.jpg
Wheatstonebridge.jpg830×466 51.3 KB

  1. Is the use of the combinatory the way to *** more strain gauges or can the HX711 handle more of the 2-wire verions?
The combinator is setup for three wire load sensors like our [[Load Sensor - 50kg](https://www.sparkfun.com/products/10245) and you could modify it to work with three resistors and a strain gauge but it's probably better that you just use a little bit of proto board [[like one of these](https://www.sparkfun.com/products/8808) and build the circuit above on it.](https://www.sparkfun.com/products/8808)](https://www.sparkfun.com/products/10245)](https://en.wikipedia.org/wiki/Wheatstone_bridge)
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thanks: will look into…