DC power jack not proper size?

I'm working on a project that will be powered by a 9v wall wart. I bought a power jack to be used with my project (mouser pn# 806-KLDHCX-0202-AC), but no power is making it anywhere in my circuit. With a multimeter, I've determined that; the wall wart is indeed providing 9v. the tip and sleeve contacts of the jack are continuous with their respective contacts outside the jack. there is no voltage across the contacts when I plug the wall wart in.

So the only thing I can think of is that the wall wart plug is not making contact with the contacts inside the jack. This is strange, because I can feel the contacts connecting when I plug the plug into the jack, and the two parts make a solid connection. I've tried this jack with several different wall warts, all with the same result.

Does anyone have any idea how I can determine if it really is that the plug and jack don't match? I'm not convinced.

Thanks!

You're sure you have the board layout correct too? Pin 1 all the way at the back is Vin and the other two are ground?

connector data sheet http://www.mouser.com/catalog/specsheets/KLDHCX-0202.pdf

Yes, the layout is correct; I went back and checked again, even tested for reverse polarity with a multimeter. I have determined (by using a dummy plug & multimeter) that the sleeve of the plug is not continuous with the contact in the jack when the plug is plugged in. I tested the sleeve contact in the jack again just to make sure the jack wasn't broken. This, again seems very strange since it looks like the contacts should be touching when the plug is connected.

Well those seem to be avalible with center pin diameters of either 2.0 or 2.5 mm. Perhaps you have a plug that excepts a 2.5 pin but your jack has the 2.0 pin?

Lefty

Sounds plausible - cable has 2.5mm hole, is not getting pushed on to the 2mm pin in the barrel jack.

You’ve measured 9V between the center hole & the outer sleeve, so the wallwart is definitely good?
(like with a resistor lead if you can’t get the meter probe in there?)

I connected the sleeve on the wall wart plug to the contact in the jack with a bit of wire, and it works. I guess the plug and jack are not compatible :(

So you are not getting ground contact then? You have both of the grounds on the jack connected in your circuit?

Yes I have this problem as well. If you don't match the centre pin's dimensions then contact is a bit intermittent. The other thing is that there are two grounds connections on the socket, one gets disconnected when the plug is in.

Grumpy_Mike: Yes I have this problem as well. If you don't match the centre pin's dimensions then contact is a bit intermittent. The other thing is that there are two grounds connections on the socket, one gets disconnected when the plug is in.

Yea, I just usually just solder the two ground lugs together, unless I need the disconnect feature for say disconnecting the ground lead to an internal battery.

Lefty

Grumpy_Mike: Yes I have this problem as well. If you don't match the centre pin's dimensions then contact is a bit intermittent. The other thing is that there are two grounds connections on the socket, one gets disconnected when the plug is in.

That's it. I only soldered to one of the ground pins, it must be the one that gets disconnected when you plug in. Thanks! Now I know what to do :)

Didn't I ask just that back in reply #1 ??