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AC input wiring
speedklz:
I have seen this before and usually it is a ground tied to nuetral somewhere and what you are reading a the voltage that occures from the nutral grounded into the ground itself or to a water pipe somewhere in the house and it can produce voltage but as stated it would be very little if any amps. so there is no problem with it. Alot of older houses have this going on it just build up a small voltage on the nutral line, kinda like static electrical charge. Nothing to worry about.
bungy:
Regardless, I think I'm going to end up using a double pole switch. I just want to keep my monitor as safe as possible.
bungy:
OK...
When I tested the voltage on my power strip on the same outlet I have been testing my arcade rig with, I got 0v when the switch was off and 118v when the switch was on. This is behavior I'm looking for, so I open up the power strip to see what he's doing differently.
Inside, the neutral is connected to the neutral bar, ground to the ground bar, and hot goes to the switch with the other side of the switch going to the hot bar. Exactly the same as my test rig. Except there are some electrical components between the neutral wire and the switched side of the hot wire (Pic 1). I don't recognize the components (looks like a resistor & ceramic capacitor, but I'm not convinced that's what they are), but I unsolder them anyway and try it on my rig. I connect them the same way, but at different points in my circuit. I even soldered in the switch from the power strip.
And I still read about 10v while the switch is off. (Pic 2)
This was supposed to be the easy part of my project, wtf is going on?
Continued in next post...
bungy:
Next plan of attack: wire in a double pole single throw switch. This will block both the hot and neutral wires when it is off. Surely this will work.
I wired up my full rig with the DPST switch and check the voltage in the off position (Pic 1). 7.6 volts. Damn. It's better than the 46v or so I was getting before, but still unacceptable.
Voltage reading is normal when the switch is on, all outlets check out with the receptacle tester. (Pic 2)
Continued in next post...
bungy:
What now? I happen to have an ATX power supply opened up on my bench and I cannibalized it for parts. It had a DPST switch connected to the input receptacle so I desoldered the whole thing and swapped it into my rig. I test the first ("always-on") outlet with the new main switch off (Pic 1). Zero volts. Turn the switch on and 117 volts (Pic 2). This is the behavior I want. But what is different? Nothing as far as I can tell. Maybe the switch is built to different tolerances.
But let's not jump to conclusions until we test the switched outlet.
Main power switch off, outlet switch off (Pic 3), 0v. OK.
Main power switch on, outlet switch off (Pic 4), 18v. WTF? At this point, the receptacle tester will glow very dimly when plugged in.
Main power switch on, outlet switch on (Pic 5), 118v as expected.
I am convinced this is not induced or static voltage. Am I doing something wrong? Does anyone see a problem with my setup?
I feel like I need an oscilloscope to troubleshoot this further.