Hi all,
First I've got to admit I'm new to this forum and am not schooled in electronics, please forgive me if the following is a Noob question or in case I could have found theanswer elsewhere (I haven't been able to findit).
I'm trying build a brewing vessel for beer. I'm controlling my heating element with an Arduino through an Arduino. For temperature sensing I'm converting my setup to rely on a pt1000. The problem is that I willneed to amplify the signal to get a reliable accuracy. For this I think i need to employ opamp's. Currently I'm trying to figure out a circuitthat would work, but haven't been able tofindsomething workable online.
As far as I've understood I should use a differential amplifier. I've drawn a circuit with a differential amplifier, where I try to make to make V1 equal to V2 when the PT1000 is at its lowest (C=0, V2 = 1/2 Vcc). The amplification would than be, R3/R2. However if I than attach Vout to an analog input I'm receiving a static value (analogin = 174-175).
I'm using an LM358n as the opamp. R1 = R3 = 330. R2 = 82. A= 330/82 =4.
Does anyone know what I'm doing wrong?
First I've got to admit I'm new to this forum and am not schooled in electronics, please forgive me if the following is a Noob question or in case I could have found theanswer elsewhere (I haven't been able to findit).
I'm trying build a brewing vessel for beer. I'm controlling my heating element with an Arduino through an Arduino. For temperature sensing I'm converting my setup to rely on a pt1000. The problem is that I willneed to amplify the signal to get a reliable accuracy. For this I think i need to employ opamp's. Currently I'm trying to figure out a circuitthat would work, but haven't been able tofindsomething workable online.
As far as I've understood I should use a differential amplifier. I've drawn a circuit with a differential amplifier, where I try to make to make V1 equal to V2 when the PT1000 is at its lowest (C=0, V2 = 1/2 Vcc). The amplification would than be, R3/R2. However if I than attach Vout to an analog input I'm receiving a static value (analogin = 174-175).
I'm using an LM358n as the opamp. R1 = R3 = 330. R2 = 82. A= 330/82 =4.
Does anyone know what I'm doing wrong?
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