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Topic: Can my Arduino UNO be powered from a normal 12 V (14.7 V) lead battery? (Read 5807 times) previous topic - next topic

clockdivider

Hello, I am quite new to electronics and Arduino, but so far I have successfully developed my own flash controller for photographic purpose.

Now I want to make the project mobile, so I am looking for an adequate power supply for my Arduino. When I am out with my photographic equipment, I have a very, very, very heavy 12 Volt lead-battery with me that powers my flashes. Now I was wondering whether I can use this battery as a power supply for my Arduino too?

Although it is written "12 Volt" on the battery, it actually outputs 14,7 Volt, so now I am afraid to blow up my board. Also: if I cannot use the battery, what kind of mobile power supply is best for the Arduino then?

Thanks a lot! Martin...

clockdivider

Too stupid! I thought 12 Volt is the upper limit to drive an Arduino, but it is only "recommended" to drive the Arduino at max. 12 Volt. I found the article "A Big Battery Adapter for Arduino".

Hmmm... What does that mean? Does that mean it  is "not recommended" to drive it at 14.7 Volts? Still a little concerned to use the big battery as power supply...

retrolefty

#2
May 13, 2011, 05:35 pm Last Edit: May 13, 2011, 05:36 pm by retrolefty Reason: 1

Too stupid! I thought 12 Volt is the upper limit to drive an Arduino, but it is only "recommended" to drive the Arduino at max. 12 Volt. I found the article "A Big Battery Adapter for Arduino".

Hmmm... What does that mean? Does that mean it  is "not recommended" to drive it at 14.7 Volts? Still a little concerned to use the big battery as power supply...


It will work. The +5vdc regulator will run hotter then if you used a +8vdc source, but the regulator has self protection and will just shutdown if you try and run it too hot or draw more current then it's rated for. I ran a serial arduino board for over a year with a regulated +15vdc laptop power pack with no problems.

If you try and power too many external componets from the arduino's +5vdc pin then the regulator will run hotter depending on the load. 

Lefty

ctdahle

It will work, but Arduino's regulator is a pretty small chip and will need to dissipate all that extra juice especially if you are pulling a lot of current through your Arduino.

Might be worth your while to rig up a 7805 regulator circuit to put between your lead acid battery and the Arduino, and fit that regulator with a heat sink. Or buy one of the little regulator kits from Sparkfun, Adafruit, etc.

It's five or ten bucks in parts to protect the Arduino, but more importantly, it's a few bucks spent to save you the annoyance of failure during a shoot.

clockdivider

Hmmmm. Yes, i felt a little unconfortable with that 20kg lead battery the small Arduino was plugged to. So I tried with a 6V lead battery with 7Ah, which I have here too... Until now the Arduino runs quite well with it, although 7 Volts are recommended. At least I cannot burn it away with that...

Thanks a lot for your help! I appreciate that very much! Thanks!

CrossRoads

You could also get a  switching regulator to make 5V nice & cool-ly for the arduino, bypass the regulator and power the board directly.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

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