Battery pack question

Not sure how I forgot this but I just noticed that the battery pack that came with my Arduino did not have the plug soldered together.

Not a problem I have the tools to do it. But I have no clue which wire goes to what lead.

There were no instructions in the box (I still have the box with the shipping contents).

Thanks for the help!


I didn't get a battery pack with any of my Arduinos. Care to share a link, a photo..?

Sorry. It is just a 9volt battery.

I'm not at home right now to take the picture.


The Arduino boards with barrel jacks have them connected so the center contact is positive, or in other words has the higher DC voltage. Use a multimeter, or even just a continuity tester, to identify what part of the “back” of the plug is electrically connected the center contact of the plug. Then connect the wire that goes to the positive terminal of the 9 Volt battery to that part of the plug. The only other part of the plug that a wire can be attached to should be connected to the negative terminal of the battery, but it doesn’t hurt to doublecheck that it’s really electrically connected to the outside contact.

MUCHO thanks! Makes sense for this non-electrical guy. LOL