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Power Connector

A project log for Power Monitor

Non-intrusive feedback loop for electrical systems.

jlbrian7jlbrian7 07/25/2014 at 02:480 Comments

This is probably old news for most people, but I just learned something today.

On the DC power connector above the red wire is connected to the center pin and the black is connected to the casing contact.  When nothing is plugged in, the center connection that is not connected has continuity with the connection with the black wire.  

When a power cable is inserted you lose continuity with the terminal that is not connected.  I believe that it is irrelevant now because I have revised my board but this was an issue with the way I layed out v2r0.  The chinese arduinos would work as is, but I was having some strange problems with the sparkfun arduinos. 

 It is a notable fail on my part because several weeks ago when I assembled the first board I had originally used the sparkfun arduino and ran into the strange problem and assumed that I had created a solder bridge somewhere  because I was lacking confidence in my smd soldering abilities.  I slavaged some parts and tossed the board aside.  

The second build, the one in the main project picture, I used the chinese board because I did not want to risk damaging a $10 board when I had several $3 boards laying around.   

Tonight I did some troubleshooting while building up a couple more boards and found the problem... I am almost always right to assume that if there is a problem it is because I did something wrong, but every now and then I need to take a closer look at the components.  I didn't know DC jacks had a switch inside. 

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