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My Arduino has problems!

My Arduino Uno is not doing ANYTHING when hooked up to an AC adapter

Model: PLM05A-050

PIN: 180-0711B

INPUT: 120V~ 0.15A, 60Hz

DC OUTPUT: 5.0V 1.0A

However, when the arduino is hooked up to a usb cable that is connected to a laptop, it works fine. What is the problem?

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...I just broke a rule...

Check the specifications on the hardware page of the Uno: http://arduino.cc/en/Main/ArduinoBoardUno

Input voltage (limits) = 6-20V

The 5V regulator on an Uno is a simple 5V linear regulator. I would not recommend going over 10V. If you draw 1A @ 5V from it and you are feeding it 10V. The regulator will have to turn 5W into heat, that is a lot and it will become very hot.

Go for the lower voltages like 7.2 V as they protect the voltage regulator from getting hot and still provide enough current.

Sorry double comment

What happens when I put in like 10v or more? Will the Arduino explode or something?

hi, That should be fine. Duane b Rcarduino.blogspot.com

after looking at the page for the UNO, it looks like one could feed 5v+ into the 5V on the board and gnd to the GND on the board, as long as you weren't planning on using a shield.

hi, you can power the arduino through vin with 7+ volts, this is enough for the on board regulator to provide the 5 volts the board needs. You can also power the arduino directly through the 5 volt pin, however you can only do this with good quality regulated 5volt supplies. If you want to use a wall wart, use a 9 volt one connected to the on board regulator through the power jack. The on board regulator will turn this into a good 5v supply for the board. The regulator drops a few volts while doing it's job, this is why you need 5 volts + 2 volts or more to get a steady 5 volts through the power jack or vin. Duane B Rcarduino.blogspot.com
You need more than 5v to run the arduino. Change your ac adapter our switch to batteries (rechargeables preferred) to get the correct voltage of over 6v. 4 non rechargeables or 5 rechargeables (min) should do the job

     First check whats coming out of the wall wort.  especially the polarity.  Adriano uses Ground on the barrel and V+ in the center.


     Also 5 volts is a bit low for the barrel jack input i use 9 to 12 because there is a regulator on the Adriano.  If you want to use a 5 volt supply you hook it up to the +5 volt and GND pins.