Amplifier 1 acts as a Straight Subtractor, doesn't seem to be working properly though.. (Used to calculate the difference between the S.P and M.V), Amplifier 2 is an inverting amp (Used to set gain) and the 3rd Amplifier is a straight adder (Used to negate offset). Can anyone explain where I went wrong with the 1st and 3rd Amp? I understand that the gain has to be set within these Op-Amps as opposed to using resistors.
