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Is Knob-and-Tube *Always* Dangerous?
Joshua Putnam wrote: Properly installed and maintained K&T is quite safe, though it would be a good idea to install GFCI outlets (properly labeled "no equipment ground"). The problem comes if it either wasn't a great installation in the first place, or if it's been tampered with or damaged. A good solder joint will last a century or longer, but a bad one can get worse over time, e.g. corrosion from leftover flux, a cold joint developing increasing resistance, etc. Depending on the age of the house, the wiring may have been soldered using irons heated over a fire, which made cold joints more likely since the iron didn't maintain a constant temperature. Many times you'll find amateurish additions to K&T systems, I've seen Romex twisted on and wrapped in duct tape for added lights or outlets. Some homeowners have blown insulation over wiring that was fine in open air, but gets too hot without air circulation. My own house was almost entirely K&T when we bought it, mostly on one breaker (and a Zinsco breaker at that), so the insurance inspection was more detailed than usual, and the inspector asked about what appliances were going to be used in which rooms so he could get a better idea of whether the wiring would be safe as we were using it. Now that sounds like a real dumb insurance company. I can understand why insurance companies have issues with K&T and may choose not to cover homes with it. But any insurance company that has inspectors running around asking homeowners which appliances they are going to use where, is surely stupid. Homeowners move appliances around all the time. Also, someone doing anything from carpet cleaning to a contractor doing home repairs can plug in various loads. Either the wiring is safe with the fusing in place or it isn't. No trouble once it was inspected and approved, but not every insurance company will accept K&T. -- is Joshua Putnam http://www.phred.org/~josh/ Braze your own bicycle frames. See http://www.phred.org/~josh/build/build.html |
Is Knob-and-Tube *Always* Dangerous?
MDT at Paragon Home Inspections, LLC wrote:
As it happens I've just been updating my list of issues that affect underwriting in Chicago and Suburbs, based on conversations with local agents. The most common issues a [SNIP] Coverage of large areas with ivy or other similar plants (for example, State Farm). Very interesting. Said family member also looked at another, quaint hillside bungalow where some sort of foliage (still haven't identified the genus and species) grew straight up to the side of the house). I never thought of insurability when I walked through it, but I told family member to demand that seller raze the entire hillside before a sales agreement was even entered into. Man, but was this place cool. High off the ground, over a two-car circa 1900 garage, in PA coal country...but all hardwoood, with a new kitchen and bath. Kewl. I could not tell whether the mold I detected was in the "un-attic-ed" second floor, due to an old roof (BUT--no leak stains) or whether the surplus vegetation, and how! was responsible for the moldy smell. EIFS or Dryvit synthetic stucco over *frame* construction. Why would this be objectionable? As it happens, the home with the K&T had unbelievable wide framing, a stone foundation and first floor, all stucco-ed over. The sills on the leaking windows (and not all windows were leaking) were wide enough for the fat lady at the opera to sing on. I'd really appreciate hearing more about this point. Frame buildings in close proximity to another structure (especially a problem in Chicago). Because of the unknown condition of the "proximate" frame home? Any fused (as oposed to circuit breaker) based systems, even if 100A in good conditon. Knob and Tube wiring For some companies, *any* electrical service less than 100A (or example, Hartford). Tell me if I'm stupid for even thinking of this solution. It turns out that the K&T home is being sold by the elderly owner because she's remortgaged herself out of existence with a new roof. (Big roof.) She said she'd "low ball" the sale to my family member IF said family member allowed her to remain in the home and rent. But because of the condition of the property, which I spent an hour walking through yesterday, I thought buying the property for *any* price was unwise. Family member persisted in wanting it, nevertheless (location, location, location). I thought, if the seller were so inclined, family member could 1) take over the home for the exact amount of the elderly seller/occupant's refi, 2) offer to pay real estate agent whatever commission he would have received from a traditional sale at the ax-ing price, and 3) use the TON of bucks she'd spend on a mortgage to rewire the home, thus getting herself the home, accommodating an old woman in a time of need, and also compensating a hard working agent. Am I living in tinfoil hat dreamland? (Please give me time to adjust the wire hanger, so I can receive your transmissions.) Previous claims or inquiries discovered during a CLUE search, especially for water damage. I ax-ed real estate agent if seller would have any objection to home inspector cutting at least a 2' x 2' piece of the soaked drywall under a leaking window off to see if any K&T is buried in the wall. Agent said he "didn't understand what I meant." And what is a "CLUE search?" Everybody, this thread should be required reading. Many opposing opinions; almost ALL thoughtful and very polite. Makes Usenet worthwhile. Tanks a lot! |
Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
Knob and tube is not by nature dangerous. The problem comes when adding
outlets to it, or when using it as a clothes line, whatever, to hang stuff from in the basement :-) I just had my old place rewired to bring it up to code. Why ... it's now a requirement in order to get insurance .... and to be honest I feel safer. The existing circuits were probably at full capacity. I had had a new panel put in, and had put in a few new circuits to the basement and 1st floor to ease that a bit, but the time had come to have all the old wiring replaced. And since an insurance company was involved, a certificate was required ... easier to just hire an electrician to do the remaining work (in my case) and to call in the inspector for that certificate. Get some estimates ... it may not be *that* costly depending on what all needs doing and the layout. Having said that, the walls will likely end up with a few full holes here and there for running the wiring ... and to be patched/painted. If that's not a problem (diy), not much of an additional expense. Consider patching/painting in that estimate. I still haven't finished all my patching ... maybe next winter :-) |
Is Knob-and-Tube *Always* Dangerous?
RBM (remove this) wrote: Never heard of such a thing. All over the NE houses have K&T, and they all have insurance. AFAIK, the NEC still recognizes K&T, so I can't imagine why insurance companies would have any problem with it Three years ago, I was denied by State Farm and USAA, but Liberty Mutual agreed to cover me with the condition that I get it all replaced within 6 months. They did not require proof, or a follow-up inspection. I'm guessing that if the place burned down due to an electrical failure of any kind, they would simply deny the claim. If you look at it a differently, Liberty Mutual said "Yeah, sure, here's your policy. By the way, your electrical system is only covered for 6 months." I have since replaced it, but it was a slow process -- my system was especially bad. Some instances included live wire stretched tightly under copper pipes (supporting them), a lamp cord hardwired into the circuit, fraying insulation, insulation that had chaffed off, overloaded circuits, outlets with grounds that didn't connect, a ceiling fan hanging by two wood screws and a piece of lath, etc. When I look back on it, I can't believe the place didn't burst into flames every morning. The problem with anyhing that's 60 years old is that people with no idea of what they're doing have had 60 years to screw with it. |
Is Knob-and-Tube *Always* Dangerous? Drifted to: CLUE and EIFS
CLUE:
http://www.insurance.wa.gov/factshee...ctShtRcdNum=13 EIFS: http://propex.com/C_f_env_EIFS_pbm.htm Note that products such as EIFS and Dryvit are NOT the same materials or application techniques as older "conventional" stucco systems. The big issue with EIFS and related materials is that they must be installed EXACTLY according to the manufacturer's instructions, not later modified incorrectly (for example, the "cable guy" leaves an unsealed hole), and carefully maintained to prevent subsequent water intrusion. The widespread problems with these materials reflects that fact that few homes are built ot maintained at this level of perfection. In the last few years newer versions of such products have attempted to address these problem (fox example, by incorporating a drainage plane), but IMO we won't know for a decade or more whether these modifications will solve the problems under "real-world" conditions. EIFS inspection is a specialized process, and EIFS inspectors are trained and certified to evaluate specific manufacturer's products. Evaluating these of these applications is an inspection nightma a tiny defect (a pencil-lead diameter hole or a hairline crack) can admit enough water to rot out a large section of wall, and the damage may not be visible at the exterior surface - the general technique is to use special moisture-meters to detect water *behind* the synthetic stucco were damage is apparent, where defects in installation and maintenance are noted, or in areas where problems are know to occur frequently. Michael Thomas Paragon Home Inspection, LLC Chicago, IL mdt@paragoninspectsDOTcom 847-475-5668 |
Is Knob-and-Tube *Always* Dangerous?
According to Pete C. :
Which reminds me; a while ago it was posted here that GFIs don't need a ground. Is that true? Could you eliminate the ungrounded risk by just replacing the outlets with GFIs? No, you need the ground. That's an important part of the whole system. You *can* use GFCIs on circuits without grounds as a retrofit. They will not provide the full protection that they do with the ground connection, but they do provide some protection. The GFCIs come packaged with labels that include a "No equipment ground" warning label for just such applications. It is still far better to just rewire if at all possible. Perhaps some explanation is in order. GFCIs on circuits without grounds is in fact NEC and CEC approved. On balance, GFCIs probably provide _more_ protection than a mere ground does. GFCI's protect against electrocution and shocks. Breakers and fuses protect against circuit overloads. Grounds will protect against electrocution and shocks, but ONLY if the fault current is above the breaker/fuse rating. A ground will _not_ protect you if you touch the hot wire or any other condition if the fault current isn't high enough. On a GFCI protected circuit, a ground is of relatively little use. But it's certainly nice to have, especially on circuits feeding electronics, especially if you want your surge/spike protector to work as well as possible. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
According to :
I wish they still used K+T wiring. It was the safest method available, except for those funky exposed scrrews on the turn switches. All they need to do is put a cover over the switches and add a 3rd wire for grounding. There are issues with insulation thickness, losing track of which neutral corresponds to which hot, box size (just try to get a GFCI into some of those old boxes), box entrance method ("loom" rather than clamps) and layout/dearth of outlets etc. Installation is also MUCH more time-consuming. But yeah, that wire is remarkably tough and the workmanship of initial install was almost always higher than current, cough, cough, "standards". -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
Joshua Putnam wrote:
As an insurance agent, I wish more home inspectors were aware of what conditions can lead to insurance problems. In defense of home inspectors: 1) The "business" end of a real estate transaction is not their responsibility, and HIs get a lot of flack (and occasionally, legal problems) if they start giving advice on such matters. 2) Even if a HI feels it's within the scope of their responsibility to comment on such matters, the insurance industry does not make it easy to discover what underwriting standards apply to a given type of structure in a given area, and the standards very considerably from company to company. So IMO it's primarily the responsibility of real estate agents and lenders to educate buyers about these issues. As for insurance agents, it appears to me that they often have an inherent conflict of interest in such matters; what's good for their customers - for example, awareness that even *just making inquires* about coverage that end up in CLUE may result in increased premiums or even loss of coverage - is not good for their employers or carriers. One reason I'm updating my understanding of local underwriting standards is that I'm putting together a presentation for real estate agent and brokers on "10 Insurance Issues You Can Spot" in the hope that this will assist them in identifying sales likely to hang up on insurance issues well before they become a ugly surprise to everyone involved. This is nice for my organization - I have the opportunity to present my company's services to Realtors, and hopefully to do something practical to reduce the mutual frustration of HIs and real estate agents with each other's role - but why should I be doing this, instead of the insurance industry?. So IMO while an occasional individual HI choose may go "above and beyond" state or Association standards of practice by spending a day with the Yellow Pages attempting to understand underwriting standards in their community, I think it's a bit unrealistic for insurance agents to express surprise or disappointment that others don't - probably most insurance agents could learn a good deal about housing defects by taking to HIs, but don't feel this is within the scope of their responsibilities either. Michael Thomas Paragon Home Inspection, LLC Chicago, IL mdt@paragoninspectsDOTcom 847-475-5668 |
Is Knob-and-Tube *Always* Dangerous?
"bowgus" wrote in message
oups.com... Knob and tube is not by nature dangerous. The problem comes when adding outlets to it, or when using it as a clothes line, whatever, to hang stuff from in the basement :-) I just had my old place rewired to bring it up to code. Why ... it's now a requirement in order to get insurance ... and to be honest I feel safer. The existing circuits were probably at full capacity. I had had a new panel put in, and had put in a few new circuits to the basement and 1st floor to ease that a bit, but the time had come to have all the old wiring replaced. And since an insurance company was involved, a certificate was required ... easier to just hire an electrician to do the remaining work (in my case) and to call in the inspector for that certificate. I think your onto the real problem now. When I bought this house only 3 of the four 110v fused outlets were being used. I ran a line from the empty(freezer) outlet to the kitchen as a temporary fix. When I got a new entrance panel in and started replacing the wiring found that almost all of the wall outlets, and the furnace, were on the same circuit. The old entrance panel was on the back porch. The wiring on this circuit wrapped all the way around the house and ended about 10' from the entrance panel. The last outlet was where we had the coffeemaker and toaster. The refrigerator had been near the end too, until I added the line. The old wiring is 16 gauge! Probably 50-60' of it. |
Is Knob-and-Tube *Always* Dangerous?
According to z :
JimL wrote: Which reminds me; a while ago it was posted here that GFIs don't need a ground. Is that true? Could you eliminate the ungrounded risk by just replacing the outlets with GFIs? No, you need the ground. That's an important part of the whole system. That's what I would assume. I couldn't figure out how a GFI could work without some sort of point of reference. But everybody said.... You don't need the ground for a GFCI to operate. Really. You merely need to route a little current from the line hot to the load neutral (or load hot to line neutral), and pop! No ground necessary. By "system", JimL could be referring to the entire "system of wiring", where grounds obviously do increase safety. But a GFCI _will_ work without a ground. That's why NEC/CEC _encourages_ their use in retrofits if you're not intending to rewire. And you have the electric field problem exactly backwards. The widely spaced conductors will carry about half the field strength of normal wiring. Those two conductors in normal wiring are both throwing off electric fields. Uh, of opposite polarity, so as you get back from them past maybe 10X the separation between them, the net field is zero? Right. Field strength of romex running current is considerably less than hay-wired K&T, because the fields are of opposite polarity, and if the wires are adjacent, as in Romex, they cancel out. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
z wrote: That's what I would assume. I couldn't figure out how a GFI could work without some sort of point of reference. But everybody said.... A GFCI only looks at the hot lead and the neutral lead. If the current in the neutral isn't exactly the same as (but opposite in direction to) the hot lead current, the breaker opens. Calling it a ground-fault is a little misleading, since it doesn't look at the 'ground', but it does look for a circuit that has faulted TO ground (earth ground, not the ground lead). Dave |
Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
In article .com,
says... Joshua Putnam wrote: My own house was almost entirely K&T when we bought it, mostly on one breaker (and a Zinsco breaker at that), so the insurance inspection was more detailed than usual, and the inspector asked about what appliances were going to be used in which rooms so he could get a better idea of whether the wiring would be safe as we were using it. Now that sounds like a real dumb insurance company. I can understand why insurance companies have issues with K&T and may choose not to cover homes with it. But any insurance company that has inspectors running around asking homeowners which appliances they are going to use where, is surely stupid. Homeowners move appliances around all the time. Most homeowners use their kitchen appliances in the kitchen, not the bedroom or the bath, so it does make sense to ask what kitchen appliances a family uses. If we used a big microwave or other high- draw plug-in appliance, that would pose more of a risk of overloading a shared circuit than if we had no microwave. Similarly, people who own high-wattage hair dryers tend to plug them in. People who don't, don't. Also, someone doing anything from carpet cleaning to a contractor doing home repairs can plug in various loads. Good points -- until we rewired, contractors were only allowed to use two outlets in the house, and one outdoors, all 20A grounded circuits on separate breakers. Either the wiring is safe with the fusing in place or it isn't. Well, since we had an old Zinsco breaker box, probably *no* wiring would have been completely safe with the fusing in place. Some insurance companies that accept higher-risk properties charge them all the highest-risk rate, others attempt to differentiate among levels of increased risk, which requires a more detailed evaluation of the home and how it would be used. The policy we had is available for either owner-occupied or rental homes, but some of the conditions that are acceptable for an owner-occupied home are not acceptable for a rental. -- is Joshua Putnam http://www.phred.org/~josh/ Updated Infrared Photography Books List: http://www.phred.org/~josh/photo/irbooks.html |
Is Knob-and-Tube *Always* Dangerous?
In article . com,
says... As for insurance agents, it appears to me that they often have an inherent conflict of interest in such matters; what's good for their customers - for example, awareness that even *just making inquires* about coverage that end up in CLUE may result in increased premiums or even loss of coverage - is not good for their employers or carriers. For me, that actually works out well -- while some companies report zero-paid-out inquiries to CLUE, the companies I work with don't surcharge for them or deny coverage because of them. So I've picked up some good customers who were turned down by other companies. One reason I'm updating my understanding of local underwriting standards is that I'm putting together a presentation for real estate agent and brokers on "10 Insurance Issues You Can Spot" in the hope that this will assist them in identifying sales likely to hang up on insurance issues well before they become a ugly surprise to everyone involved. This is nice for my organization - I have the opportunity to present my company's services to Realtors, and hopefully to do something practical to reduce the mutual frustration of HIs and real estate agents with each other's role - but why should I be doing this, instead of the insurance industry?. Good question. I have done group discussions with Realtors on insurance underwriting concerns, and they've always been very receptive to the information, and they refer buyers to me when the buyers have insurance questions. It's good business for me, and it helps them avoid insurance surprises at closing. I expect it should work well for you, too. On the subject of CLUE reports, almost any time I'm in front of a group of realtors or loan officers, I offer to reimburse the first person who goes on-line to order their own CLUE report as a demonstration of how it's done. More than half the time, that person finds something they didn't expect -- maybe a claim they had forgotten about, or a prior claim on their house, or an inquiry that was mis-reported as a claim. That almost always gets half the group ordering their own CLUE reports and asking about what they find. Makes it much more personal and memorable for them. -- is Joshua Putnam http://www.phred.org/~josh/ Braze your own bicycle frames. See http://www.phred.org/~josh/build/build.html |
Is Knob-and-Tube *Always* Dangerous?
"Tekkie®" wrote in message . .. posted for all of us... I don't top post - see either inline or at bottom. statistics show K&T has more troubles Quote these statistics - include the source I'm sure that the insurance companies are just considering the age of K&T wiring when the consider it for insurance purposes. If K&T is used, it is pretty darn old. Since it is so old, it has probably been messed with. .......... Bob |
Is Knob-and-Tube *Always* Dangerous?
Joshua Putnam wrote: In article .com, says... Joshua Putnam wrote: My own house was almost entirely K&T when we bought it, mostly on one breaker (and a Zinsco breaker at that), so the insurance inspection was more detailed than usual, and the inspector asked about what appliances were going to be used in which rooms so he could get a better idea of whether the wiring would be safe as we were using it. Now that sounds like a real dumb insurance company. I can understand why insurance companies have issues with K&T and may choose not to cover homes with it. But any insurance company that has inspectors running around asking homeowners which appliances they are going to use where, is surely stupid. Homeowners move appliances around all the time. Most homeowners use their kitchen appliances in the kitchen, not the bedroom or the bath, so it does make sense to ask what kitchen appliances a family uses. If we used a big microwave or other high- draw plug-in appliance, that would pose more of a risk of overloading a shared circuit than if we had no microwave. Sure it makes sense. Like 2 years later someone won't buy a microwave and plug it in where you didn't have one when the inspector looked? Or buy a freezer and put it in the basement? Or your kids won't plug a hair dryer in God knows where? Or add a window air conditioner? Similarly, people who own high-wattage hair dryers tend to plug them in. People who don't, don't. Yeah, right, that's a good way to determine if a place is safe to insure. Try to figure out where they or a guest might plug in a hair dryer. Also, someone doing anything from carpet cleaning to a contractor doing home repairs can plug in various loads. Good points -- until we rewired, contractors were only allowed to use two outlets in the house, and one outdoors, all 20A grounded circuits on separate breakers. Either the wiring is safe with the fusing in place or it isn't. Well, since we had an old Zinsco breaker box, probably *no* wiring would have been completely safe with the fusing in place. Then I not only wouldn't insure it, as an owner, I'd get it fixed. |
Is Knob-and-Tube *Always* Dangerous?
Tekkie® wrote: posted for all of us... I don't top post - see either inline or at bottom. statistics show K&T has more troubles Quote these statistics - include the source -- Tekkie if it wasnt a problem insurane wouldnt care... this does everyone a good service since the home that burns might be one you are visiting. the poster who mentioned blown in insulation made a excellent point thats a bad combo that can lead to overheating. middle of the night once I turned on a bedroom light and got a shower of sparks on bed, geez did I wake up fast. bad wire insulation in light socket. I replaced every single fixture like that! not worth the risk, since at the time they were about 45 years old. |
Is Knob-and-Tube *Always* Dangerous?
Those two conductors are throwing off opposite fields that will cancel. This is why clamp on amp probes (not the new hall effect type) have to be clamped around just one of the conductors. Pete C. Sorry Pete, you are full of it. Maybe if the conductors were twisted, you would have cancellation, but otherwise there is no measurable cancellation. |
Is Knob-and-Tube *Always* Dangerous?
According to JimL :
Those two conductors are throwing off opposite fields that will cancel. This is why clamp on amp probes (not the new hall effect type) have to be clamped around just one of the conductors. Pete C. Sorry Pete, you are full of it. Maybe if the conductors were twisted, you would have cancellation, but otherwise there is no measurable cancellation. Of course there's cancellation. The EM fields are opposite in polarity, and immediately adjacent to each other in romex. That means that they cancel. "Maybe if twisted..."? What do you think twisted pair is for? Twisted pair accentuates the effect. But simply paralleled conductors are almost as good. It's K&T which has higher fields because the conductors aren't (usually) parallel, and (also usually) _much_ further apart. Standard "clamp-ammeters" etc need to be applied to just one conductor. Otherewise, they give highly misleading results. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
JimL wrote:
Maybe if the conductors were twisted, you would have cancellation, but otherwise there is no measurable cancellation. Would you have any evidence for this article of faith? Nick |
Is Knob-and-Tube *Always* Dangerous?
one day soon ALL conductors will be required to be inside metalic
conduit, power lines will all be migrated to underground too, appliances will be shelded and service cords will get braid ground shielding like coax has. theres a high core;lation between expoosure to electrical feeds and cancer. this will be the next asbestos....... |
Is Knob-and-Tube *Always* Dangerous? holler butt
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Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
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Is Knob-and-Tube *Always* Dangerous? holler butt
Again quote FACTS - not opinions. One of the other posters whom is an insurance agent stated basically "it depends" Insurance co's determine their own ratings and the FACT that some WILL insure it blows your OPINION out of the water. Please note ALL your postings involve opinion and you never quote facts. When you are called on it or corrected you ignore or change the subject. -- Tekkie fact is many insurance compnies wouldnt cover K&T that you cant deny. some appear to cover it, probably at higher rates. think about this..... what does homeowners coverge cost maybe 500 bucks ours is less and we have full replacement coverage Have friends with home fires just smoke damage can cost 20 grand, that was my next door neighbor his car caught on fire in his driveway, caught a window on fire with brick home, 20 grand how many policies do you have to sell to make a profit? insurance is oing all of us a favor, and while your asking me what type of wiring in YOUR HOME? |
Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
George E. Cawthon wrote: wrote: one day soon ALL conductors will be required to be inside metalic conduit, power lines will all be migrated to underground too, appliances will be shelded and service cords will get braid ground shielding like coax has. theres a high core;lation between expoosure to electrical feeds and cancer. this will be the next asbestos....... Bull! there is no correlation. Real studies don't even find a correlation with people living near or under high tension lines. You probably also believe that cell phones cause brain tumors. Course even if they did, smashing into the guy in front of you as you drive along lost in your conversation would be a lot more dangerous. Mixed studies but wheres theres smoke theres fi( have a friend who works for a cell phone company he believes geadsets are the future getting antennas away from brains... look at all the things once believed safe.... smoking, asbestos, outdoor wood, DDT, agent orange, and a long list of others.... |
Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous?
According to George E. Cawthon :
wrote: one day soon ALL conductors will be required to be inside metalic conduit, power lines will all be migrated to underground too, appliances will be shelded and service cords will get braid ground shielding like coax has. theres a high core;lation between expoosure to electrical feeds and cancer. this will be the next asbestos....... Bull! there is no correlation. Real studies don't even find a correlation with people living near or under high tension lines. There have been a few studies that have shown _some_ vague correlation with HT lines. However, as some of these researchers point out, HT line corridors are _also_ dosed with herbicides where toxicity is far better understood and that's the much more likely _real_ culprit than EM fields. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
According to JimL :
No, there is no cancellation unless you twist the pair and then the reduction is only minimal.. The EM fields are opposite direction and overlap. Why would they _not_ cancel? Not completely, of course, because the fields aren't perfectly coaxial. But more than a few wire separations away, pretty good. May I suggest you take a course in electronics? -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
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Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
z wrote:
Tekkie® wrote: posted for all of us... I don't top post - see either inline or at bottom. one day soon ALL conductors will be required to be inside metalic conduit, power lines will all be migrated to underground too, appliances will be shelded and service cords will get braid ground shielding like coax has. theres a high core;lation between expoosure to electrical feeds and cancer. this will be the next asbestos....... What baloney... Holler Butt quote facts! You ain't got them. I will sleep comfy on my electric mattress pad. -- Tekkie Snip New electric blankets pair the wiring in opposite directions, so once gain there's negligible net field. (I got an old one I've always meant to try feeding with a rectified and somewhat filtered supply but I notice nobody else has tried this for some reason; any comments?) The controls for the electric blanket will not handle DC. Switching for DC loads must be much more robust then that for AC. -- Tom Horne "This alternating current stuff is just a fad. It is much too dangerous for general use." Thomas Alva Edison |
Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
According to Tom Horne, Electrician :
The controls for the electric blanket will not handle DC. Switching for DC loads must be much more robust then that for AC. Depends on how the controls work. I thought they were (still) usually variable resistors with thermal cutoffs to act as cutoff timers. That'd work just as well on DC. If, on the other hand, they're using SCRs or Triacs and the like, you'd have to change the controller. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
Tom Horne, Electrician wrote: New electric blankets pair the wiring in opposite directions, so once again there's negligible net field. (I got an old one I've always meant to try feeding with a rectified and somewhat filtered supply but I notice nobody else has tried this for some reason; any comments?) The controls for the electric blanket will not handle DC. Switching for DC loads must be much more robust then that for AC. I was afraid of something like that. Well, on behalf of my epidermis which dislikes my habit of getting it burned, etc. with my various experiments, thank you. -- Tom Horne "This alternating current stuff is just a fad. It is much too dangerous for general use." Thomas Alva Edison |
Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
Chris Lewis wrote: According to Tom Horne, Electrician : The controls for the electric blanket will not handle DC. Switching for DC loads must be much more robust then that for AC. Depends on how the controls work. I thought they were (still) usually variable resistors with thermal cutoffs to act as cutoff timers. That'd work just as well on DC. If, on the other hand, they're using SCRs or Triacs and the like, you'd have to change the controller. Definitely nothing that fancy. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
Is Knob-and-Tube *Always* Dangerous?
wrote:
George E. Cawthon wrote: wrote: one day soon ALL conductors will be required to be inside metalic conduit, power lines will all be migrated to underground too, appliances will be shelded and service cords will get braid ground shielding like coax has. theres a high core;lation between expoosure to electrical feeds and cancer. this will be the next asbestos....... Bull! there is no correlation. Real studies don't even find a correlation with people living near or under high tension lines. You probably also believe that cell phones cause brain tumors. Course even if they did, smashing into the guy in front of you as you drive along lost in your conversation would be a lot more dangerous. Mixed studies but wheres theres smoke theres fi( have a friend who works for a cell phone company he believes geadsets are the future getting antennas away from brains... Yes mixed studies, just scientific ones and ones based on emotion. No fire, no smoke except that produced by lawyers and quacks. look at all the things once believed safe.... smoking, asbestos, outdoor wood, DDT, agent orange, and a long list of others.... Poor examples, anyone smoking for the first time knows it isn't good for you (what do you think all that coughing is about?); asbestos wasn't considered safe, just not desperately dangerous (which it isn't except for that mined from one specific area, and mainly dangerous only to the miners); outdoor wood? (what kind of wood isn't outdoor wood and how dangerous is it except for falling on you; DDT isn't that bad for humans, it was banned because it is dangerous to bird reproduction and indiscriminate use was bad for the environment; agent orange was always bad, just some people (military, government) said it wasn't to decrease liability; and on an on. Your main premise is not bad--we learn that stuff is dangerous to us after a period of time. Maybe you should have mentioned red dye#1--used in early margarine and causes cancer. But electrical fields have been around quite a while and studied thoroughly. |
Is Knob-and-Tube *Always* Dangerous? OT & holler butt crap
On Fri, 28 Jul 2006 19:44:09 -0000, (Chris
Lewis) wrote: According to Tom Horne, Electrician : The controls for the electric blanket will not handle DC. Switching for DC loads must be much more robust then that for AC. Depends on how the controls work. I thought they were (still) usually variable resistors with thermal cutoffs to act as cutoff timers. That'd work just as well on DC. A variable resistor here would be very inefficient. If, on the other hand, they're using SCRs or Triacs and the like, you'd have to change the controller. -- Mark Lloyd http://notstupid.laughingsquid.com "Democracy is two wolves and a lamb voting on what to have for lunch. Liberty is a well armed lamb contesting the vote." - Benjamin Franklin |
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