Leaving My Arduino On For Extended Periods?

Using Arduino General Electronics
1

Hello all! Ryan here. I've got a question...
I'm powering my arduino with a 10.5V DC wall-transformer that I procured from my local thrift store.
Is it ok to leave my arduino on for extended periods of time with this input voltage?
I know that the hardware page for the UNO (http://arduino.cc/en/Main/ArduinoBoardUno) says that 10.5V is within the recommended input voltage range, but is it ok to leave my arduino on for a long time with this input voltage?

I am having it drive a 9x9 LED matrix. needless to say, there is considerable current draw from the transformer.
approximately 50% of all of the LEDs will be on at the same time. also, I'm using POV so only 9 LEDs are on at any given time.
After letting my UNO run for around 5 minutes, I pressed my finger against what I assume to be the 5V regulator and found it was warm. Not hot, just warm.

So my final question is this: What is the maximum period of time you would allow your UNO to run under these conditions?
I would greatly appreciate any advice/help that you could give me.

Kind regards,
Ryan

2

Also, I thought that the resistors I used might be relevant. I used 220 Ohm resistors for every column of LEDs.

Ryan

3

The arduino is fine being left on permenantly. What will probbly fail first is your cheap power supply.
Check no components are getting too hot, that is too hot to keep your finger on.

4

I have been running a standalone arduino 5x5x5 led cube for over a year non-stop powered from a thrift store 5.1vdc cell phone wall wart power module. Works great.

5

thanks for the replies! And the advice!
I'm powering mine with a regulated 5V supply appox 4.99 volts consistently. is it ok to have the 5V power supply connected directly to the 5V and GND pins on the arduino?

Kind regards,
Ryan

6

is it ok to have the 5V power supply connected directly to the 5V and GND pins on the arduino?

Yes.

7

thanks grumpy mike.