This is stupid and lame

kunkmiester · Post by **kunkmiester** » Fri Feb 17, 2012 6:50 pm

My acer's power cord broke. I figured a new 3 prong plug from walmart would fix it, and cheaper than a whole new cord, right? The old plug ended up off the cord completely, so I was down to relying on color coded insulation.

Only the green(ground) is colored. The "white" wire isn't individually insulated either, so I have two black wires to figure out which goes where.

I can't find ANYTHING saying which of the connectors on the OTHER end of the cord is supposed to be live. If I could just figure that out, say a picture with the contacts labeled, I could get it together. Right now it looks like pray it has good protection, and see if the battery starts charging or not, and then reverse the wires if needed.

ladajo · Post by **ladajo** » Fri Feb 17, 2012 6:58 pm

Just crack the case at the other end. My money says that you will find one black as "hot", one black as "neutral", and the green as case ground to earth. Which in home wiring is neutral anyway.

Normally, the equipment end is a three prong triangle residing in a rectangle shape. The two on top (residing level with each other) are hot and neutral. The bottom in the middle is case ground.

BTW, it actually matters not which is hot and neutral in single phase. It will feed the primary of a step down, and then immediately get rectified on the secondary.

But, if you care, you can crack the case and see. Then if you are further concerned, you can pop the cover on the wallplug and see which tab is hot, and which is neutral/ground.

kunkmiester · Post by **kunkmiester** » Fri Feb 17, 2012 7:15 pm

I knew the one was earth, but the other two...I just noticed BTW that one of the wires has lettering molded into it, but again, not sure if convention says that's live or neutral.

ladajo · Post by **ladajo** » Fri Feb 17, 2012 7:45 pm

Normally, the "marked" lead is the neutral. So if you have a raised ridge or stripe on one, that would be connected to neutral. The solid/no marks or ribs/ridges would be "hot".

Green is ALWAYS ground for power connections.

krenshala · Post by **krenshala** » Fri Feb 17, 2012 9:43 pm

darn, I can't remember if the charger board is before or after the PSU in notebooks. Too long since I did work on them. Memory thinks it was input jack, power supply (which converts to DC) then the charger board, but I'm not positive of this.

ladajo · Post by **ladajo** » Fri Feb 17, 2012 10:01 pm

You are talking about the wall cord right? Which then connects to the adapter, that then plugs into the jack on the laptop?

Another thing you can do is find a buddy with the same or very similar cord and ring it out with a meter.

kunkmiester · Post by **kunkmiester** » Sat Feb 18, 2012 12:15 am

Got it figured out--saw that the stress relief on the plug was molded around the cord, so the markings and alignment are just barely visible. It works and hasn't set the apartment on fire yet.