Hello,
I created a quarter wheatstone bridge and am trying to use the change in voltage to determine the amount of strain in the strain gage. I am using a multimeter and measure the voltage between the two pins and am getting a reading that is usually 80 mV or around 100 mV. I know it should be 0 if the bridge is balanced but for some reason it isnt, so I am assuming my zero value is about 90.
However this is not my problem. Every time I connect cables from the breadboard to the analog input, it increases the voltage from 100 mV to around 2.5 V. Does anyone know why this is happening?
**video file was too large so im including pictures
img 3169 is the circuit not connected to the analog input and the multimeter reading 90 mV
img 3170 is the circuit connected to analog Ao5 and the multimeter reading 2.5 V
Thank you so much in advance
SS.ino (597 Bytes)