Hot chassis circuit made safe?

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Over the years I have seen my share of stupid electrical tricks.

We lived in the same small house in Florida for 37 years. Cable TV came to us sometime in the late 80's. They installed a drop from the pole out back to the box on the outside of the house and grounded it to the copper water pipe feeding the outside faucet where the house electrical service drop and wireline telephone were also grounded.

Small town cable companies were getting eaten by larger companies, and ours was gobbled up several times by bigger fish that ended when Comcast bought the franchise from AT&T. Everything pretty much stayed the same except for the prices.......

Sometime in 2013 A Comcast tech came to the house while I was at work, told Sherri that he had to upgrade the wiring on the outside of the house. He was there for about 10 minutes and left. Later that night I noticed a faint buzz in the sound and faint hum bars on the TV. I decided to check the connections on the back of the cable box, and when I took the cable connection off the back of the cable box there was a spark and I got a shock.

There was about 40 volts of nasty AC between the ground side of the incoming RF cable and the chassis of the cable box. WTF?????

The next morning I went outside to investigate the "wiring upgrade." The ACE cable guy had disconnected the water pipe ground that had worked fine for over 20 years and installed a clamp on the fat electrical conduit that goes between the electric meter and the master breaker / disconnect box. OK there was a #10 wire running between the electrical box and the water pipe ground behind the stucco, so these were the same ground.....no big deal.

My first call to Comcast was met with an idiot who said that the problem was probably in my TV system. They would send a tech out and if the problem was inside my house I would be billed $45 for the service call. I had already been down this road with them before so I told them that I would check it out myself......


After fixing things for over 50 years I have learned that if it worked before you messed with it, and it was broken after you messed with it, you f......

Super ACE cable guy had put his "ground clamp" on a PLASTIC piece of conduit! In the process he had left the setscrew loose in the water pipe ground clamp when he pulled his wire out, thus removing ground from the house electrical service and wireline phone system. The entire house now had a floating ground. A quick check of my neighbor's house revealed the same "upgrade." Did this whole block of 7 houses now have no ground?

I made a second call to Comcast. This time I explained that their ace tech had modified my cable wiring and in the process removed the grounding from the ENTIRE house wiring system and the phone system (AT&T). This was a serious violation of the National Electric Code, which resulted in me receiving an electric shock, and my next three phone calls would be to the city building inspector, Florida Power and Light, and to AT&T since my electrical and phone service drops were now ungrounded and thus in violation of the NEC due to poor work by Comcast.

This got some attention. A "supervisor" said that a technical "expert" would be at my location "soon." I explained that I was already late for work due to their incompetence, and if their expert wasn't there before I was ready to leave, i would make the three phone calls and go to work.

About 20 minutes later a Comcast guy showed up who did have more than two working brain cells and knew that the little pipe between the two boxes was plastic and that there was no ground. He explained that there was some reason that they were no longer allowed to "bond" their systems to water pipe ground, they had to use electrical system ground. That may make sense in newer neighborhoods where much of the water system was plastic, but our neighborhood was developed in the mid 70's when water service was all copper, and a pretty good ground.

He put it back the way it was, but the wire had been cut shorter by "Ace" so he just ran it straight across the wall where it would be easily snagged by my lawnmower or even the fence gate. Someone else would come back to do it right within a day or two.....2 years later I sold the house and left Florida for good. It had never been done right.

I showed the expert the mess on the house next door, and he was going to fix it. He was still working on another house on the next block when I returned for lunch several hours later......apparently there was a bunch of this "upgrading" going on.
 

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...I finally convinced him to decommission his death cable.
Good man! Some people do need to be saved from their own stupidity. Thank you for resisting the urge to let him fry in his own fat!

On the Aussie Guitar Gearheads forum, a member once described finding a mains extension cable which had been modified to have a male (plug) on both ends.

The proud owner pointed out that it could be used to easily connect a gasoline generator to his shop wiring by simply plugging one end into a generator outlet, and the other end into any outlet in his shop. :eek:

It could also be used to revive any mysteriously dead set of wired-together electrical outlets, by plugging one end into a good outlet and the other end into the cluster of dead outlets. :eek:

Apparently the fact that you had 240 volts AC on exposed pins, waiting to electrocute someone, wasn't a concern worth worrying about. :eek:


-Gnobuddy
 
Super ACE cable guy had put his "ground clamp" on a PLASTIC piece of conduit!
<snip>
...there was some reason that they were no longer allowed to "bond" their systems to water pipe ground
Sounds like a classic case of the first cable guy knowing just enough to be (extremely) dangerous. :eek:

I would have thought anyone who was being sent out by his employer to intentionally modify mains ground wiring would have been required to have electrical certification. :confused:


-Gnobuddy
 
Good man! Some people do need to be saved from their own stupidity. Thank you for resisting the urge to let him fry in his own fat!
As it happened, his own place did have grounded outlets, so he wasn't using his invention in the living room rig I was working on. If he hadn't brought it out from somewhere to show me, I might have never known about it! I think he was proud of his idea.

The thing is, I like this guy. I still run into him from time to time, and enjoy catching up & shooting the breeze with him. He seems like a decent human being, if not the brightest bulb on the tree. I felt like I had to thread the needle - I didn't want to belittle or scold him, but at the same time I really wanted to make sure he understood how dangerous this thing was. I was relieved, upon meeting him some time after the service call, when he told me without prompting that he'd realized his mistake and wasn't using his cheater cord.

On the Aussie Guitar Gearheads forum, a member once described finding a mains extension cable which had been modified to have a male (plug) on both ends.

The proud owner pointed out that it could be used to easily connect a gasoline generator to his shop wiring by simply plugging one end into a generator outlet, and the other end into any outlet in his shop. :eek:
Hee! I wonder if he expected this procedure to fill his generator's tank with gasoline! :D

It could also be used to revive any mysteriously dead set of wired-together electrical outlets, by plugging one end into a good outlet and the other end into the cluster of dead outlets. :eek:

Apparently the fact that you had 240 volts AC on exposed pins, waiting to electrocute someone, wasn't a concern worth worrying about. :eek:
I think another important point to make with clever folks like these is: If this was really a good idea, you could go to the store and buy one!
 

PRR

Member
Joined 2003
Paid Member
....There was about 40 volts .... had left the setscrew loose in the water pipe ground clamp .... The entire house now had a floating ground.....

The question I don't want to ask: you "should" still be bonded through the power line. The "N" of your feeder tied to the ""N"" of the street-line, which "should" have ground electrodes every few poles.

Yes, residential power ""N"" is never zero-current and you expect a few volts drop to true dirt. I have 0.3V-4V G to N depending on load. But 40 Volts??

I would bet on some malpractice by Florida Power and Light. (I bet that is a safe bet in any case.) Their best "ground" may have been you and your seven neighbors' hose faucets.

Because I have significant G-N voltage here, I get hum-bars unless I bond power, telephone, and cable at multiple points. Restoring a "lost" bond at the meter-pole helped some. Adding another cable bond as it goes past the fusebox gets it down to negligible.

Cable workers "do not need electrical certification" because their work "never" impacts electric power installations. (Yes, George's clever idiot found a way to do that....)

This is one reason we are now supposed to have Intersystem Ground Bars. 4+ screws, nobody should have to tamper any other service's grounding. IMHO, you want one inside for inside splitters and cable modems, one outside for overhead drops and antennas.

I do have a male-male power adapter. Yard-sale find. I have actually used it to bring power from garage to outdoor outlet to isolated basement outlet to give light while I was replacing the fusebox. I keep it out of sight.
 
sent out by his employer to intentionally modify mains ground wiring

In "Ace cable guy's" defense he probably didn't see the bare piece of #10 wire protruding from under the stucco and going into the ground clamp from the back side. I knew it was there because I visited the construction site nearly every day while my house was being built. He probably had a memo or a work order telling him WHAT to do, but not HOW to do it, and certainly not how to test the continuity of the ground. The cable drop should have been grounded at the pole, and the power ground was connected to the water mains. There should be a low resistance between these two, certainly not 40 volts, which I still do not completely understand.

About 10 years prior to this there was an event in an apartment complex where residents were awakened in the middle of the night to exploding TV sets and cable boxes. Fortunately nobody was hurt or killed and there were only a couple minor fires. This turned out to be corroded grounding by the cable company (before Comcast, but on the same cable system) and a piece of underground electrical feeder (7200 volts) breaking down and arcing through the wet ground to the cable company's line......those two should NOT be near each other.

Now, in the "that's no excuse for stupidity" side of this, these houses had been build continuously the same way for over 15 years when mine was made and for another 6 or 8 years until all the available land right up to the edge of the swamp had been built out. About 6,000 houses which were nearly identical were built. Comcast had to know how they were built, and could have conducted at least 15 minutes of training before sending a team of aces out to "rebond" a large bunch of houses.

I sold the house and left Florida for good......this is my favorite part of the whole story.

I grew up in rural Dade county but by the time I left home the city of Miami and it's suburbs had grown to enclose the house I grew up in. In 1973 at age 20 I moved about 40 miles north to western Ft. Lauderdale.

The Motorola plant where I got a job was surrounded on 3 sides by cows, LOTS of them. We were in the middle of the largest dairy in Florida. It has since moved Northwest.

House prices rose from $20K to over $35K in 4 years as the people started displacing the cows, then started climbing exponentially as empty land vanished. In 1977 I bought my "starter house" and lived in it for 37 years.

I got married in 1985 and told my wife that I didn't like "big city Florida" and would move to her small town in West Virginia once I got laid off. I never planned to stay at the same place of employment for 41 years, but it happened, and I actually accepted a deal to "lay myself off" and helped find my replacement in 2014.

By that time I really was ready to leave Florida for good......In two days it will be the 5th anniversary of my last day at Motorola. I still visit the former Motorola plant every July. There is still a small group of a few hundred people renting a small section of the former plant which has been sold and is now home to medical coders, insurance people and Magic Leap, a VR headset company funded with Google's money that hired a bunch of ex Motorola people.
 
The question I don't want to ask: you "should" still be bonded through the power line......which "should" have ground electrodes every few poles.

EVERY pole in south Florida, and possibly the whole state. With the water table only a few (like 3) feet below the surface a good ground is pretty easy to get. When I put up my ham radio antenna I buried an old (dead) 4 cylinder engine block about 5 feet from where the metal water pipe emerged from the ground and entered the house, and connected a fat wire from the block to the mast. It measured about 2 ohms to the water pipe with a couple mV of AC on it. The resistance between the water pipe and the house wiring ground was less than one ohm. This was at least 10 years before the cable incident, but my guess is that something was floating in the cable system, not the power feed. If it was FPL, a lot more stuff would have blown up. Note...and open neutral WILL blow stuff up, and the evil "shared neutral" was used in these houses.

I do have a male-male power adapter.

I made something even more stupid. A 50 foot piece of Romex with a 240 volt 30 amp twist lock plug on one end, and 3 large alligator clips on the other end. It served it's purpose, and no longer exists.

In 2005 hurricane Wilma hit south Florida and wiped out the entire power grid. We had no power for 22 days. This is no fun in the Florida heat, so I devised this method for powering two essential necessities from my gasoline generator...my house AC unit, OR my pool pump. The AC sucked a bit more power than the generator was rated for so I only ran it for an hour or so right before bedtime. I ran the pool pump for a couple hours a day from the 240 volt outlet while the refrigerator a fan and the TV was plugged into the 120 volt outlets. The 12 volt outlets were used to charge two boat batteries for lights, the fan and the TV at night. We had to be very stingy with power since a neighbor had to drive almost 2 hours north every 3 days to get gasoline. Gas stations can't pump gas when there it no power.
 

PRR

Member
Joined 2003
Paid Member
> about 2 ohms to the water pipe

Here on rock, at the lower edge of the septic field, that would be nearer 120 Ohms. I figure the 5 rods and stray guys on my land barely touch the 25 Ohm NEC goal.

I pulled a boat-converted Chevy Six out of the driveway but I don't think it was a grounding electrode. Just fill.
 
On the Aussie Guitar Gearheads forum, a member once described finding a mains extension cable which had been modified to have a male (plug) on both ends.

I used to work with a guy who had done the same.

He had a loft (attic) extension but there was no power. So he wired a ring circuit in and then made up a double male extension lead. He plugged one end downstairs and the other in one of the outlets in the attic. Problem solved :cool:

One day his son, for whatever reason, unplugged and handled the end that bites :eek:

Fortunately he survived the resultant shock.

The bit that annoyed me was the guy chastised his boy for 'being stupid' when IMO he was the idiot.
 
that would be nearer 120 Ohms.

I lived about a half mile from the levee that separated the humans from the alligators. There was about 100 miles of swamp just west of us. If you dug a hole more than 2 feet into the ground it started filling with water.

I don't think it was a grounding electrode. Just fill.

That was my original intention since a Chrysler 2.2L engine short block was cheaper than concrete. I just connected a fat wire to it and found that it was a pretty good ground.
 
The bit that annoyed me was the guy chastised his boy for 'being stupid' when IMO he was the idiot.
I couldn't agree more. Talk about being an irresponsible parent. :mad:

I bet the twit hadn't even bothered to add a warning label to both ends of the cord. Something like "DO NOT TOUCH! Due to my stupidity, you might die if you unplug this cord." :mad:

At least both PRR and George both knew exactly what risks they were taking with their male-male and male-alligator cords. I'm sure they both took precautions to prevent children, pets, or family members from coming into accidental contact with the dangerous end of the cord.


-Gnobuddy
 
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