Tuesday, September 18, 2012

Project Clean Up Part 1 Chapter 2

Chapter 2 "Why the White Wire is Hot"

This is a continuation, the First part is Here,  a complete list is available under "Ham Radio Master links" on the sidebar.

I didn't want to button my power supply up before figuring out why the hot wire was white. Basically, I wanted to make sure this radio could work anywhere, and having a hot white wire was troubling. Like David suggested in his comment, I suspected the outlet, and then the wiring in the Mains box. Time to flip breakers and do some inspecting!
First, I flipped the breaker to the shack, and trundled back into it, hoping to find a black wire where a white wire should be. The Shack in the Back was built before we moved here, and is 'unfinished'. The guy who owned the place two owners ago built it with scraps left over from some of his contracting jobs I think. When I unscrewed the socket from the recepticle, everything looked, well, fine. I was impressed with the craftsmanship of the socket to tell you the truth, connections were tight, and in the right place. Time to check the mains box, but I knew it was going to look fine there too. It did.
Back to the thinking bucket.
Yon Thinking Bucket

I juiced the shack back up, grabbed my VOM, and began doing things my mother told me not to do, namely sticking metal things in electrical outlets. By metal things, I mean VOM probes. I always feel weird sticking things into electrical outlets, makes me make sure I do so with fear, and caution. That's not a bad thing, I suppose.
First, I checked the socket for power, Hot wire to neutral, and I got 120v AC. Good!
Then I checked for what should be the neutral wire to ground, and got no AC voltage, Good!
for the kicker, I checked what should be the Hot wire to ground, and got 120v AC, Good!
So the socket is good! Should have done that first instead of assuming it wasn't... hmmm.

Next test, the power supply strip I plug into the socket. Maybe there's something miswired there,
Just checked Hotside to ground, 120v AC. Good!
So the power supply is not the issue.
must be the power cord.

The Cord- Not Polarized

notice that in the picture of the plug end, the plug is not polarized. This plug and wire was salvaged from some piece of computer equipment, and at one point in time had a female chassis mount plug on it, the kind that looks like this:

Female Chassis Mount

On a polarized plug, the narrow slot/prong is hot, the wide slot/prong is neutral and the round prong is ground, my non polarized plug fits in the socket the way a polarized one would, but, was it wired like a polarized socket? Just where did the white wire go?
I made sure the plug was unplugged, clipped the cord out of the power supply, and I decided to idiot check the green wire first, green for ground right? Switching my VOM to measure resistance, I continuity checked the green wire to the round prong, and it was Good! Then I checked between the other two wires, and no other wire lead to the round prong, Green is good!

I then oriented the plug like I was about to plug it in.

Right is hot, left is Neutral...

As this picture shows, the prong on the right, goes to the hot side of the socket. That's the one I want to check.
First I check the black wire, no continuity.
Then I check the green wire, no continuity.
Finally, I confirm that the right prong, the prong that normally connects to the hot side of the plug is connected to the white wire.
The white wire is hot because it goes to the hot side of the socket.
I have no idea why this cord is made this way.
I just know that I can safely button up the power supply knowing It's the Cord, not my shack!

Next Up: Chapter 3: "Totally Tubluar Transmission and Technical Tidbits"
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