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    Trouble understanding shunt resistance for short-circuit current measurement

    Thanks a lot for your comments. I've updated the circuit diagram, which can be found below. Indeed the voltage ADC inputs were all connected, which is now not the case anymore because they are placed between the cell and the switch, which is now placed on the positive side of the cells. I...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Hi all, thanks again for being so supportive. I'm uploading here one block diagram explaining the procedure and what the system must do, and a circuit diagram as an possible way to implement this. 100mv across the solar cell would indeed be perfectly fine for this application, even 150-200mv...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Thanks a lot for being so generous with your time and knowledge. I think I got the common-mode signal issue now! Again I did some more research and testing before coming back to post. First, I should mention that the budget is extremely limited - virtually 0 except the available material, which...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Thanks a lot for these two comprehensive replies. They are really helping me to better understand the challenges that I face. Again, I've been researching based on your comments, especially concerning the amplifiers. First, I should comment on the general procedure regarding the FF and MPP. I...
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    Trouble understanding shunt resistance for short-circuit current measurement

    So in my circuit I only need one amplifier, which would amplify the voltage drop over the shunt resistance. I am now doing some research regarding which kind of op amp I could use. Is this very important? I was thinking of using a non-inverting amplifier. Can I simply connect the inverting input...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Dear all, Thanks a lot for the very valuable tips. I've been researching based on your advice. Indeed, I need to measure the MPP. However, the MPP can be obtained with MPP = FF * Voc * Isc. In other words, if the FF is determined, the MPP can be calculated by onls measuring the Voc and Isc...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Thank you for your valuable input. Indeed, powering the system is a logistical issue, but the Arduino itself and a SD module, without LCD, will not use lots of power and a couple of large batteries in parallel, charged overnight, can be used for that. I just found the ACS711 which offers a 12...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Thanks a lot for these very helpful replies. Indeed I didn't explain well enough what my goal is, sorry for that. First of all, the whole setup must be very portable, because it will be brought to the field under real sunlight. Sunny days will be chosen, ideally in a desert or some place with...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Thank you so much for this comprehensive and helpful answer. I have some comments and doubts: - Cells in series: Indeed, I cannot use this method because I need to compare cells. - AREF: Indeed, I was thinking of using the internal resistance of 1.1V, and calibrate it in advance, which gives me...
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    Trouble understanding shunt resistance for short-circuit current measurement

    Hi all, I'm trying to measure and log the short-circuit current I_sc of a single solar cell (0.5V-6A) with an Arduino and am having trouble with the setup of the circuit. I'm a beginner with electronics, please take this into account. Basically this is where I am at: -I understood that the...
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