[ProAudio] Proper Grounding Replies

Dick Pierce dpierce at cartchunk.org
Tue Nov 5 10:29:24 EST 2019

On 11/5/2019 1:09 PM, Bill Whitlock wrote:
> It reminds me of the "expert" audio system grounding advice I read on the internet:  "As long as 
> one piece of your equipment is grounded, the rest is protected via the signal interconnects."  
> Can you imagine fault currents of 150 A to 1,000 A (typical, from a UL field study) flowing in 
> RCA cables for a few seconds?  I see nothing but flames!

So, what would likely happen is either the RCA connector would
be vaporized or welded in place. I see either as an improvement :-)

Let me throw another anecdote or two at you:

In a previous home, the next door neighbor was a logger, and was a couple
cords short of a full load. He borrowed a friend back-hoe,, and as we was
unloading it off the trailer, he didn't notice he had raised the bucket
all the way up. The bucket cut the service entrance and pulled it partially
off the pole. Our light immediate;ly dimeed, other went out. I hit the
breaker right away, called the power comany, then went and measured the
feed coming in. One side to neutral was dead, the other side was about
60 volts, but was jumping up and down by a bunch at a semi regular
interval, perhaps by 20-30 volts. I looked out the window and there was
the guy trying to shake the wire off the bucket. Why he didn't electrocute
himself climing out of the back hoe or, perhaps, why the electricity gods
decided to spare him is beyond me.

The other incident happened, ironically, on the same pole. I'm working in my
office, there's suddenly a blindingly intense blue glow coming in through
the dinwos, followed almost instantly by the apocryphal 60 Hz terminated
after a couple of second by a large pop1, then silence. And no lights.
Called the fire department, pulled the breaker, and went outdoors to explore.
Got out there about the same time as the local police did, and we start
searching and, after a a wee bit of time, we found the partially charged
and smoking remains of a squirrel, with enough of its head, frozen in
the middle of saying "oops".

|          Dick Pierce           |
| Professional Audio Development |
|         cartchunk.org          |

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