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Topic: Solar panel + Battery monitor (250W panel, 120AH battery) (Read 49 times) previous topic - next topic

tr1p1ea

Hi all, I am pretty new to the scene and was looking for some advice on building a small Arduino based monitor to augment my basic PWM Solar regulator with a little display to show information. Proposed board is an Arduino Nano. I have searched the forums however I couldn't line any results up with my particular system - apologies if there is already an appropriate thread.

My setup is a 250W solar panel that has a 20A PWM regulator that charges a 120AH AGM battery. A 12v portable fridge is the load for the system as crudely shown below:

250W Solar panel
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20A Solar regulator (basic PWM) ----> Portable 12V fridge (+ Arduino and sensors)
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v
120AH AGM battery

I am wanting to measure:

Solar Volts IN (figuring a scale of 0-25V will suffice)
Solar Amps IN (panel max is 15A)
Battery Voltage level (would a scale 0-15V be suitable?)
Load (portable fridge) Amps being drawn (averages 0.83A/hr according to specs) + Arduino & sensors etc

From reading I see that most people use a 2-resistor voltage divider to scale input voltage appropriately for the Arduino. I haven't yet done the math on what values would be appropriate.

To measure current I had just got a couple of ACS712 hall sensor boards (30A) off eBay.

Would this be the recommended way to go? Any pointers would be greatly appreciated!

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