I just bought a replacement charger for my Fujitsu Lifebook AH532, but it seems like it has the wrong polarity. The backside of the laptop has a label saying it should be like this: https://imgur.com/0IgstAe. That's also how the original charger looks. The site I ordered from had a picture of an adapter that looks to have the right polarity, although it's kind of blurry. However, the adapter I received had it reversed: https://imgur.com/a/dWuh4

As I understand it, it could damage the laptop if you use a charger with the wrong polarity, but some places I've read say it could be fine.

Is it possible the adapter I received is mislabelled? And if it's not, what could the consequences of plugging it into my laptop be? I don't have a battery for my laptop anymore, in case that's relevant.

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    \$\begingroup\$ Measure it with a DMM. If the polarity is wrong, don't use it, send it back, and buy one from somewhere more reputable. As it stands the question doesn't appear to be about electronic design, and there are already questions on the effect of reverse polarity. \$\endgroup\$ Sep 9 '16 at 13:42
  • \$\begingroup\$ What they all said. | If you can be SURE it is (polarity reversal confirmed with meter) then if you do not want to return it you COULD cut the lead and swap the wires A-A B-B changes to A_B B-A and solder and insulate BUT you need to be certain you know what you are doing. \$\endgroup\$
    – Russell McMahon
    Sep 9 '16 at 15:42

It will most likely fry your notebook if you plug power in reverse. I would NOT do that.

Take voltmeter (DMM) and measure voltage on your new adapter to verify polarity.


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