3-wire strain gauge - HX711 Issue

Question

I have two, three-wire load sensors (https://cdn.sparkfun.com//assets/parts/4/5/9/5/10245-01.jpg) hooked up in a half wheatstone bridge (I think), with two 1K resistors. Using a multimeter, I am reading small voltage changes when applying pressure to either strain gauge, when measured on between the pins A+ and A- on the HX711 ADC amp, however my Arduino serial output shows all 0's when using a variety of code examples (for example, this one: http://www.dfrobot.com/wiki/index.php/Weight_Sensor_Module_V1#Sample_code).

My concern is that my circuit is not setup correctly as I am fairly novice, however everything I have researched about wheatstone bridges, and half wheatstone bridges seems fairly straightforward, and seems to match my circuit. Any guidance/advice on the attached breadboard circuit diagram would be extremely helpful.

Answer 1

In your diagram, the fixed 1KΩ resistors both tie to +5V at one set of ends, and their other ends tie to A+ and A-. The strain gauges are from A+ to ground and A- to ground.

In a typical scale, where several strain gauges are similarly loaded, that topology will produce about zero volts between A+ and A-. By contrast, the following topology (from: blog.l3l4.com) produces higher voltages for higher loading. (Diagram uses S+, S- rather than A+, A-)

(I realize your question shows some voltage changes when sensors are separately loaded, so this answer might not be relevant to your current problem.)