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Topic: Measuring voltage from solar panels (Read 2261 times) previous topic - next topic

MitkoDyakov

Hello,
I'm working on a solar tracker project click. I have to measure the voltage generated by the panels. Each panel maximum out put is 0.5v and 1amp of current. Is it ok to connect the panels in series and then connect them directly to analog input pin? The maximum voltage they can produce is 1v, so it is in the range 0-5v. I'm concerned about the 1amp part. I really don't want to screw my Arduino, so i decided to ask first.
Thanks

SurferTim

#1
Sep 05, 2012, 02:05 pm Last Edit: Sep 05, 2012, 02:14 pm by SurferTim Reason: 1
Voltage is the big thing. You should be fine with a direct connection as long as the voltage remains below 5 volts. A solar panel's open circuit voltage is pretty stable.

edit: I would use a small value resistor (200 ohms or so) between the solar panel and the Arduino pin. That way it is not enough resistance to affect the reading, but will prevent a pin blowout in the event you mistakenly set that pin as an output.

MitkoDyakov

#2
Sep 05, 2012, 02:17 pm Last Edit: Sep 05, 2012, 02:27 pm by MitkoDyakov Reason: 1
I have measured it with a multimeter and it never exceeds 0.5 volts, even with the biggest lap i could find. Thank you, kind sir.

edit:    GND------(-) [Panel] (+)--------[200ohm]-------[ARDUINO] is this what you mean ?

SurferTim


tlharv

If planning to use solar to power an Arduino, is the procedure normally to build your device, then test its overall power needs, then select the appropriate panel (or panels in series) to power it?  How would you test its consumption - plug it into a Kill-a-watt monitor?

SurferTim

According to his original post, it is a solar tracker, not charger. Those panels will only aim the main panel.

cmiyc


How would you test its consumption - plug it into a Kill-a-watt monitor?

I was under the impression kill-a-watts were meant to measure AC loads.  A multimeter would be sufficient to measure a (relatively constant) DC load.
Capacitor Expert By Day, Enginerd by night.  ||  Personal Blog: www.baldengineer.com  || Electronics Tutorials for Beginners:  www.addohms.com

MitkoDyakov


According to his original post, it is a solar tracker, not charger. Those panels will only aim the main panel.


This is correct. This is not solar charger. The thing has 2 servo, bluetooth, rtc and e thermometer, no way you can power those with the kind of solar panels mounted on the tracker. I will become software engineer (hopefully) this year. The project is part of my graduation exam. I had the task to write the software for a solar tracker, but I've decided to make the "real" thing instead. Building stuff is fun  ;).

MitkoDyakov

I've made the modifications today and everything worked, thanks for the help.

SurferTim

Quote
I will become software engineer (hopefully) this year. The project is part of my graduation exam.

Good luck to you. This is why I do this.  :)

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