And he heard in the background....;
Johann Sebastian Bach,
"Toccata and Fugue in D minor, BWV 565"
Johann Sebastian Bach,
"Toccata and Fugue in D minor, BWV 565"
How to remove ground pin on power cable
I had a similar issue and I just removed the ground wire from the ground prong. (I checked with the cable manufacturer first before I proceeded.) No issues and no sound degradation from using a cheater plug. Simply remove the screws from the plug and then push aside the ground wire from the prong and make sure that is doesn't touch anything else. |
UL943 governs GFCI in the US, with Mexico/Canada having similar specs, and I believe EN specs are similar. - 2003 update to improve surge suppression to protect components. - 2006 updated to detect some miswiring - 2015 added automated testing and a whole host of required fault detection w.r.t. the proper operation of the circuit. Newer GFCI should be much safer than old ones w.r.t. guaranteed operation. Self check is once every 90 minutes. GFCI outlets have more stringent requirements on what happens when a fault it detected compared to GFCI breakers, but most new breakers on the market appear to be adapted the more rigid requirement to disconnect power, not just indicate a failure. Was looking at some of the controller chips and they will even detect ground/neutral faults, and will check for failures more often. |
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Yikes if you insist on the removal of the ground pin at least install a GFCI receptacle in the place of the standard outlet. In the event your sub has an issue it will trip before any damage to person or property."According to a 1999 study by the American Society of Home Inspectors, 21% of GFCI circuit breakers and 19% of GFCI receptacles inspected didn’t provide protection, leaving the energized circuit unprotected. In most cases, damage to the internal transient voltage surge protectors (metal-oxide varistors) that protect the GFCI sensing circuit were responsible for the failures of the protection devices. In areas of high lightning activity, such as southwest Florida, the failure rate for GFCI circuit breakers and receptacles was over 50%!" See https://www.ecmweb.com/basics/article/20901772/how-gfcis-work A GFCI will only help if the CBLF is grounded and not contacting the neutral. A GFCI will not trip if the CBLF is between Hot and Neutral. If you have GFCI, test them monthly and after any electrical event, preferably with an external tester. |
Yikes if you insist on the removal of the ground pin at least install a GFCI receptacle in the place of the standard outlet. In the event your sub has an issue it will trip before any damage to person or property. Some of you do not have the understanding of how an electrical system functions. Stick with what you know. It is dangerous to advise on thing that can cause damage to people and/or property. Remember true intelligence is knowing when not to advise. |
While it's not likely to get a shock from a sub, if it was grounded, I would try and keep it that way. The ground loop is most likely from cable TV. Unscrew it and see. Find a way to break the ground there. Jensen Transformers is a good solution.https://www.jensen-transformers.com/home-theater/video/ |
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First off Nemesis. After a talk with a "Sales rep"? You are going to "possibly", cure a hum problem by removing the ground pin from a piece of gear? And this was deduced by the, "Sales Rep" using this, "information", which you provided about this, "Ground loop" right? That info came from where and was offered in what context and by whom? Seriously, Doesn't the above kind of sound like a classic case of, "The blind leading the blind"? With both parties about to walk happily off the precipice of a very tall cliff and into oblivion. Would you have a "Frontal Lobotomy" procedure done after being diagnosed by your "Bank Teller"? There are other ways to fix your "Hum". Many are listed above. "It sounds to me like your subwoofer itself may be the issue". Just please , don't take anymore "Electrical" advice from someone whom you do not know and have never met. And please, don't burn your home down or worse by following it..... "Miller Carbon"? This quote; "You've got millivolts of voltage potential on that neutral wire, we can eliminate that infinitesimally micro risk that hasn't caused a single death in a million man-years." And we said, "I don't have the foggiest what "potential" means but "voltage" sounds scary so yeah sure go for it." That is the most moronic statement I have seen here on Audiogon. When you talk about other subjects which you know nothing about it really is not a big deal. But when you give advice which could really hurt someone? Especially when you also then argue your little, "point", after several have pointed out this fact? That isn't just ignorance. It is wrong. So quit. Other than the "FACT", that a " neutral", or "bonded conductor", not only "Can" kill but HAS and indeed DOES kill people all the time? Plus the fact that you do not have any understanding of "Electrical potential"? And also seem not able to "Take the hint", when people are trying to be nice. Other than that. I am sure you are a "Hell of a guy". "Or Gal"..... By the way, this is from me, someone whom went to the trouble to become a,"Licensed" electrician. |
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It may help everyone to think about two separate advancements that have occurred in home wiring. I’m rusty on the full history, but if you’ve done any upgrades you may have felt like an archeologist, and learned about a few things. 1 - The invention of the polarized plug. When this happened some makers, like lamp makers did in fact use this as a ground. So long as the impedance is near zero, no problem.... but if that lifted for any reason like a loose wire, corrosion etc. voltage at the lamp could happen. 2 - The separate ground conductor which evolved over a few iterations, not sure exactly the timing but:
Edison didn’t come up with these ideas. They were created out of necessity. Today gear with a metal exterior must be grounded OR be double insulated. This is why my plastic body blender has no ground, but my stainless coffee pot does. I think there may be some exception for gear with outboard, low voltage supplies (i.e. wall warts) too. |
The reason, as I recall, for neutral and ground being separated has to do with Ohms law. Neutral is a working conductor in the sense that it SHOULD normally carry 100% of the current the hot does. So, 15-20 amps in a typical residential application. Due to many factors, the impedance of neutral can become significantly non-zero. 15 A * 0 Ohms = 0V 15 A * 5 Ohm = 75 V etc. etc. So it is quite possible, if not probable that neutral can be non zero. Now imagine if that the ground wire no longer exists (as in old homes/appliances), but the chassis of your equipment is bonded to neutral (old washer/dryers). See the problem? You now have gear which can develop a significant shock factor by touching it. Happened to me with an old dryer once. :) The entire point of a safety ground in appliances is to have any voltage which accidentally touches the chassis to drain to ground and hopefully blow a fuse or breaker. Of course, faults can happen in the ground conductor as well, but operationally, if the ground develops a high impedance, it’s not going to normally develop a voltage because current = 0. This part is kind of important: Because each panel can introduce a new impedance problem, the neutral and ground must remain unbonded except at the service panel. The service panel is the first one after the meter. So, if you add subpanels, you run 4 conductors. +120, -120, Neutral and Ground. One trick here is that the ground may form a loop. You don’t necessarily have to pull the ground from the panel....but that leaves open the possibility of a future contractor not knowing this, so don’t. This concludes my Ted talk. |
Adding E F F E C T I V E ground rods ain't just hammering in another piece of copper. These links are worth reading. Earth Ground Measurements https://www.polyphaser.com/News/DownloadFile?downloadGuid=c68ebee3-baa1-470e-b61c-ac0bc2f97eba Ground Impedance https://www.polyphaser.com/News/DownloadFile?downloadGuid=3c633c3a-8c65-4585-8226-48edf2813252 Ground Rod Theory Installation https://www.polyphaser.com/News/DownloadFile?downloadGuid=25400030-29fb-4981-862f-c24c4118b556 AC Surge Protection https://www.polyphaser.com/News/DownloadFile?downloadGuid=c7d58ebd-2dfc-454b-bb08-4641bad5955b |
millercarbon So you guys think its fair to nitpick me to death, then remove my post so people don’t get the explanation.No one here has nitpicked - they've corrected your profound errors, that you then punctuate with proclamations such as: That's how I defend my position. By being right. Works every time.It seems to me that others here have been more respectful of you that you have of them. Your post could only have been removed by moderators so if you're unhappy that it was deleted, your ire should be directed to them. |
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Millercarbon has been deservedly schooled here so I’m reluctant to pile on. But he is just so ignorant on electrical circuits and electrical safety! millercarbon The two wires in a two wire system, only one of them is hot. That’s your 120V. The other wire is ground. Technically called neutral but this brings up the first redundancy. There’s ground where any voltage potential goes into the actual earth ground. A rod driven deep into the ground. The neutral wire is also ground ...No, the neutral wire is neutral; it is not ground and that’s an important distinction. Electricity always wants to flow back to the source - not the ground. That’s why an aircraft can have a functioning electrical system even though - obviously - it can have no "ground." But it does have a neutral that flows back to the source. I don’t by the way have a whole lot of respect or patience for "code". Having learned from a journeyman electrician and having wired a whole house, twice, my experience with "code" is some moron making you re-do a whole weeks work because he thinks you should have an extra 1" of wire in the box. Or 1" less. They are that retarded.I’ll just echo what others have said here and suggest that you do not know what you are talking about. I have a friend who is a master electrician. He’s done some exceptional work at my house. He is often confronted by potential customers who want him to take shortcut on a project, which he’ll refuse, citing code. When the potential customer asks what the purpose of the code is, he recites the same two-word answer: "Somebody died." And that’s exactly how the electrical codes (and other building codes) have evolved. The third wire, the true earth ground, is merely another redundancy.No, it’s not redundant and if you understand the difference between neutral and ground, you’d understand that. The third wire is safety ground. The neutral wire is neutral. So now you know. That’s how I defend my position. By being right. Works every time.You’ve clearly been shown to be completely wrong on this entire topic and that you refuse to learn reveals much, much more about you than you realize. |
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Jim, I appreciate you taking the time, and also spelling it out in a way easily digested by a layman. I’m out west, in Oregon. The AHJ here for years was the State Electrical Inspector, most were great with one exception. A few years back, that responsibility fell to the local county inspector, presumably with a few courses under his belt, and the State’s blessing. The PUD has never had any requirements that I’ve been aware of regarding the location of the ground rod(s), so they are always located beside the footing, from what I’ve seen. Bear in mind it’s pretty wet, here. The only real difference I see here is the lack of a bond to the water pipe. I understand everything you’ve written on that, and can’t disagree with any of it. But it’s just never done here, NEC or no. Just about all new homes are PEX, from the meter, so there’s that. But even in the earlier ones, it just hasn’t been done to my knowledge for about 25 years here. I’m sure you understand exactly why it’s an issue. I’ve been under so many homes where the ground was clamped on the nearest copper or iron pipe, which was sometime later rendered worthless with modern repairs. Obviously the fault lies with the choice of the original clamp location. Once again, thank you. |
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miller, you are still missing the point, and in a big way. The ground is a safety device, carrying current to ground (rather than the home-owner) in the case of dangerous malfunction or device failure. The ground has nothing whatsoever to do with the actual circuit. The neutral isn't, it's a conductor. It isn't used as a safety device. And as far as my "charming story", of course I realize what you, in your boundless arrogance, seem to think I could never have thought of. I understand completely that nothing plugged in at my house was ever grounded. Hadn't gotten that far yet, in the scheme of things. Everything else was, though. The metal box, which you wouldn't normally contact, and thru it, all the metal in every switch, outlet, light fixture, heater, etc, etc, all grounded. |
miller, as much as I appreciate 99% of your posts, I’m not sure how you defend your position on this. It’s simple. The ground is the only safeguard in the event that any metal item becomes energized due to an equipment defect or failure. You're right it is pretty simple. The two wires in a two wire system, only one of them is hot. That's your 120V. The other wire is ground. Technically called neutral but this brings up the first redundancy. There's ground where any voltage potential goes into the actual earth ground. A rod driven deep into the ground. The neutral wire is also ground, only in the common layman's sense of grounding. I don't always get all pedantic in explaining. The ones who know will understand and the others will get triggered and then I can pick and choose whether to ignore the ones who get triggered or try and explain. I say try because it hardly ever works. Oh well. I don't by the way have a whole lot of respect or patience for "code". Having learned from a journeyman electrician and having wired a whole house, twice, my experience with "code" is some moron making you re-do a whole weeks work because he thinks you should have an extra 1" of wire in the box. Or 1" less. They are that retarded. Meanwhile, in other "code" I have to install hurricane clips to hold my roof on. We have yet to record a hurricane in Seattle. Code can, as the Robert Duvall character in Jack Reacher would say, "Suck it!" Our house was built in 1952. I can't tell you what the code requirements may have been then. Jim may know. Everything was wired with two-conductor cables, forerunner of romex, I guess. All the boxes, etc, were metal, and they all were connected with a dedicated ground wire, one to the other. Wonderful story. Really. Charmed. What that has to do with anything I haven't the foggiest. Look. Those old homes. Forget the metal boxes. Forget they are connected. Forget they are grounded. Why? Because I want you to think of something evidently never occurred to you before. All those outlets they have how many plugs again? Oh yeah- two. And the stuff you plug into them? Two wires, right? One hot, one neutral. Just like I said. So now here's the question: When your whatever it is connected with two wires somehow gets energized, of what use exactly is the metal outlet box being grounded? Anyone? Beuller? None. None at all. What happens is the component, the whatever it is, the neutral wire carries the charge right back to the utility ground. Just like it always does. Which is why nobody electrocuted themselves all those decades using the old system. Never had anything to do with the outlet boxes being grounded. That my friend is what we call a redundancy. Never did have anything to do with the safety of the stuff plugged into it. Not until the third wire came along. Technically, not even then. The third wire, the true earth ground, is merely another redundancy. What happened, as if anyone cares, is people with real lives became so wealthy and so comfortably numb they didn't care when the morons who think 1" more or less in the box really matters came along and said, "You've got millivolts of voltage potential on that neutral wire, we can eliminate that infinitesimally micro risk that hasn't caused a single death in a million man-years." And we said, "I don't have the foggiest what "potential" means but "voltage" sounds scary so yeah sure go for it." So now you know. That's how I defend my position. By being right. Works every time. |
@builder3 AFAIK, the Earth safety is for when lightning hits the electrical service, meaning the power from the street. The mesh of earthed neutrals in the neighborhood might just carry enough current to limit the damage. Sadly, modern building codes remove all those nice tall utility poles with their fat earths, leaving my roof the highest object in the neighborhood for a ¼ mile. If my house gets hit, all bets are off. |
ieales, I've seen 2 homes that have been struck by lightning, which isn't that common here. One was older, one very new. The lightning certainly made it's way to ground alright, used about a fourth of the home to do so, including even the framing and siding. The ground wire at the panel was sorely outmatched, shall we say. I think the service mast was blown clear out of the wall on the older home, IIRC. Small sample, no idea what "normal" may be. |
miller, as much as I appreciate 99% of your posts, I’m not sure how you defend your position on this. It’s simple. The ground is the only safeguard in the event that any metal item becomes energized due to an equipment defect or failure. Our house was built in 1952. I can't tell you what the code requirements may have been then. Jim may know. Everything was wired with two-conductor cables, forerunner of romex, I guess. All the boxes, etc, were metal, and they all were connected with a dedicated ground wire, one to the other. I’ve yet to find a fault in any of it, I’ve probably modernized 30% of the home, at this point. There wasn’t a three prong outlet anywhere, (not sure if they existed at the time) so you’re on your own with the toaster, etc, but every box, switch, plug, etc, was grounded. Somebody knew it was important then. It still is. L. |
Erik, thanks. Your last post is generally in line with my observations. (I’m a builder, been 31 years). Everything gets dedicated ground rods now. No waterpipes, no Ufers cast in the foundation, etc. It’s not that a buried line wouldn’t normally be sufficient, it’s that there’s too much potential for it to become rendered ineffective though ongoing plumbing modernization and repairs. It’s happening at my house currently, nearly 70 year old water line feeding the home, big section of it is going away, replaced with PEX. Jim, thanks as well. I’ve read your answer about six times. I understand what it says (pretty sure), but don’t understand why. Can you offer an explanation. At anywhere beyond the most remedial, I don’t comprehend the interaction of the neutral and the ground, when they’re bonded, when they’re not, etc. I realize this may be a tall order, if so, just say so. Thanks |
Which like I said, ignorance and irrational fear abounds. Now you know we have two grounds, the utility ground everything has plus the redundant earth ground they made us add.Like most everything, mc is ignorant on electrical wiring. There is one ground and that is the utility neutral. The Earth safety [ground rod, Ufer, copper pipe] is connected to it in the event lightning hits the electrical service. The Earth safety takes the current to earth, not the neutral. The Earth safety on equipment is to prevent the chassis becoming live in the event of accident or failure. Nervous Nanny: 1. remove safety ground pin 2. slide heavy amp w captive cord into rack 3. pinch cable between amp and rack, cut through insulation to hot lead 4. drop amp 5. cut off toe I see SatTV and Cable 'grounded' to hose bibs on houses plumbed with PEX. |
millercarbon: There always comes a point in every discussion of electricity where the common sense ends and Nervous Nancy and the Technobabbler’s take over. This is it. The end of the common sense. And now, without further ado, performing twenty five shows a day for endless nights only, our encore presentation of Nervous Nancy and the Technobabblers! That's some kwisatz haderach level presience there, fellas. |
From some posts here, apparently many homes continue to be grounded via the water line. This hasn't been acceptable ( up to code ) in decades. I mean, there's no requirement to fix this, generally, but you may no longer rely on copper pipes for new construction and upgrades. You MUST use grounding rods (sometimes more than 2, depends on soil conditions) for the electrical ground and they must connect to the neutral only at the service entrance. Any sub panels must maintain the ground/neutral separation. There are some requirements to ground copper pipes, which I forget why, but you don't use them as electrical safety grounds. Not only are the connections iffy, but with modern water pipes using mostly plastic it is quite easy to find an older home which has plastic in the middle. |
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Don’t cut the grounding 3rd pin off the male plug; it voids a warranty if it’s still in effect. Same for any DIY ’surgery’ to defeat it... Besides, it’s likely there for a good reason. Like keeping your hide intact. Instead, try a simple test 1st. Insert a 3>2 ’cheater plug’ that comes with the separate ground wire. (These are also colloquially referred to as a ’dead man plug’.....Gee, I wonder why.....}. Turn your unit back on. Listen for annoying noise. If it’s gone, wonderful. If not, problem is elsewhere. Bonus points and curiosity cure: Ground wire to the central screw that holds the cover plate of the wall box. Hum returns, Bingo. Hum still exists....Well, fook....*L* I had a similar hum issue a while back.....had nothing to due with the AC lines....faulty interconnect RCA cable....took a while to find That... |