Load cell sensors not showing correct values.

[kangxiongloh]

Hi,

I’m using a TI Burr-Brown INA126 Op-Amp with 2 load sensors 50 kg from SparkFun and it was working previously. But when I pressed my sensors now, that are not much changes in the readings.

Hope you guys can help me out. Thanks.

 

[Reloadron]

You really need to post the circuit(s) you are using.

Ron

 

[kangxiongloh]

Oh so sorry was new here!

I was patching my circuit accordingly to page 7 of https://www.ti.com/lit/ds/symlink/ina126.pdf

I used a 1k potentiometer for the RG between pins 1 and 8. My 2 sensors' signals to pin 2 and 3. Pin 4 and 5 to gnd. Pin 6 to output. Pin 7 connected to 5v.

Wonder what's wrong with this setup..

 

[Reloadron]

The INA will handle a single sensor as shown in figure 4 of the data sheet. You could use multiple sensors maybe in a delta configuration. You mention the circuit originally worked?

Ron

 

[kangxiongloh]

Ya it was working previously. I went to dismantle everything and re-setup my circuit again few days ago and now it's like this. When I turned the potentiometer now, my dmm readings shows voltage ranges from 0.6xx volts to 4.4xx volts. I stopped at a certain value for example 0.8 volts and pressed either one of my sensors, it would only have a 0.2-0.4 volts increment or decrement. Previously it was a 2.xx volts increment or decrement.