I have just read another thread sort of in relation to this but my situation is a little different.
A couple of months ago I decided to plug my cable tv's providers RF cable into my capture card. Thats where it basically ended. Everything except the RAM module and chassis were cooked!
The facts of the situation and my notes are:
I unplugged the power supply cable from the PSU, and attached the RF cable to the capture card (for 1sec).
*Monitor power was still connected and monitor still plugged into pc.
The house outlet that is plugged into a surge protected power board, is powering the monitor (although turned off) and was powering the pc (now detached), has been deemed to be reverse polarity.
4th of July is nothing compared to my 1st of August!!!
My AC tests with a basic multimeter conclude that the chassis of the pc was "hot" (110V) when tested to the tv cable which is earthed independently across the road as well as being shocked when holding the tv cable in one hand and touching the chassis with my other. For some strange reason, now it only reads 50V. When tested between the chassis and the outlet earth, of course I get 0V.
My question is, will a reverse polarised outlet cause damage this extensive when a foreign earth is introduced to the situation? Or is there something else that is causing the outlet to be faulty?
Also why has the reading changed from 110V to 50V? and it does fluctuate slightly at different times.
When I now AC test the outlet it reads: (where active is the small slit, neutral is the large slit and earth is the 1/2 round pin)
Active > Neutral = 110V
Active > Earth = 50V
Neutral > Earth = 50V
When the above circumstance is recreated using a correctly polarised and correctly earthed outlet, the reading between the chassis and the RF cable is of course 0V.
Is anyone able to conclude from this information that tis is a defective outlet? Will a reverse polarity cause the chassis to be hot in the first place?
Any response of information will be extremely valuable and thankyou in advance for any information.
Recommended Answers
Jump to PostIf the PSU was unplugged the voltage didn't come from there, and the only other source that you have given is the coax cable, take a reading between the center conductor of the coax and ground, and test it for polarity...is it DC voltage? The ground could be sourced back …
Jump to PostHey hell, I'm no electrician - I'm a home handyman. And we have a bit different wiring here in Ausssie to you lot. But what you're describing sounds like exactly what happens when some dill hooks up a live wire to an earth wire somewheres in the house circuit. It'll …
Jump to PostOkey dokeys. Like I said I'm a home handyman not an electrician. Readers Digest Home handyman books are the go with me, not circuit testers and wiring diagrams.
Without wading my way through reference resources and the like, one thing slaps me in the face from all that.
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Jump to PostThis gets better by the minute...I definitely would want to see just what that ground is attached to, if it doesn't go back to the pannel then you could experience transient current. I'm curious about what you're finding when you meter this out, with the line and neutral reversed you …
Jump to PostAlso a main point I am trying to conclude is, that if the situation was was that the outlet was reverse polarity and the earth was completely good, or non-existant the effects of reverse polarity wouldnt cause the chassis to be live anyway?
Okay. To clarify:
'Reverse polarity' means …
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