Question About Amperage On Wall Wart

Please excuse - if i'm posting in the wrong forum - i really need a "misc" forum but didn't see one, so here goes.
My device calls for a 12V 250 ma . The wall wart that i have is 12V 500 ma. can i use it without damaging my device. I'm obviously not very knowledgeable about ohms law or electronics. would app an explanation that a layperson can understand.
thanks
evelyn

 

Hi Evelyn, yep you can probably use it, The 12V relates to the voltage and this is important and the 250mA relates to the maximum current that the wall wart can deliver. So the 500mA means it can deliver twice the current if needed so if the device can run on a 250mA wall wart then the extra current won't be needed and the wall wart will possibly run a bit cooler because it has power in reserve.
Two things you should check
1. Is the polarity correct on the connector going to the device.
2. Are both wall warts AC voltage output or the more usual DC voltage output as the new one should be the same as the original.

Here is a cut and paste for checking whether it is DC output and the polarity of the connector.
The DC symbol looks like this: http://i968.photobucket.com/albums/ae163/joffa666/DC_zpszgaqfcpf.png

To check the polarity, look for a + or – sign next to the voltage. Or, look for a diagram showing the polarity. It will usually consist of three circles, with a plus or minus on either side and a solid circle or C in the middle.
If the + sign is on the right, then the adapter has positive polarity:
http://i968.photobucket.com/albums/ae163/joffa666/plus_zps4t8em9mo.png

If there is a – sign on the right, then it has negative polarity:
http://i968.photobucket.com/albums/ae163/joffa666/minus_zpsihzevuyi.png

Please note:-
If it is an AC output adapter then polarity isn't really an issue.

 

many, many tks 4 reply joffa - and thanks for an explanation that i can understand. you did great. wish the geeks had a "catch all" forum such as misc. for odd ball posts such as this one that don't really fit in any of the designated forums.

thanks again

 

Pleased to help and BTW you could have posted in Hardware ........I am sure if the post upset a Mod or Admin they would move it......... we are fairly casual around here so no problem.

FYI sorry the last diagram is a link because for some reason I couldn't post a third image in the reply and when I tried direct uploading all three images as thumbnails they only appeared as http://text and I didn't have time to muck about so I just loaded the three images via a Photobucket account :rolleyes:text saying img or a symbol meaning file not found and I didn't have time to muck around so just linked the pics to a Photobucket account