Reply to "How to determine DC positive wire and negative wire from a wall plug transformer?"

bigkidOGR Forum Member SUPPORTING MEMBER

On an analog meter if the polarity is wrong the needle will attempt to go backwards (what usually happens IME is you see it jerk slightly, then nothing, as opposed to no voltage, where it won't show any sign of movement.

Easiest way to tell is put the leads to the wire, if it doesn't move, reverse it and see if it moves. If it doesn't move at all, wall wart isn't working.

8/14/227:01 PM

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