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Repairing Lightning Damaged Tv's
I have no knowledge about repairing televisions, so I thought I'd ask
here, All 3 of my tv's have been damaged by lightning , 2 of them wont even power up and the other one is in black and white now(is a color tv). Just wondering what I could do to repair my tv's? Thanks |
Repairing Lightning Damaged Tv's
CJ:
Other than suggesting that you enroll in a consumer electronics repair course I would think that you would be best advised to take your televisions to a qualified technician with the proper training, necessary test equipment and replacement parts. This is not a job for the inexperienced novice...... not only is the circuitry complex but a television is one of the more dangerous electronic devices in your home. -- Best Regards, Daniel Sofie Electronics Supply & Repair - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "CJ" wrote in message m... I have no knowledge about repairing televisions, so I thought I'd ask here, All 3 of my tv's have been damaged by lightning , 2 of them wont even power up and the other one is in black and white now(is a color tv). Just wondering what I could do to repair my tv's? Thanks |
Repairing Lightning Damaged Tv's
Oog. Sorry to hear about that... did all of them get damaged at once? If
you live in an area frequented by lightning, the best thing to do is unplug the sets in advance. That's the best surge protection there is, and it's free. Lightning can damage/destroy all manner of things in a set, and even if you do manage to find and replace the troublesome components, there's no guarantee that something else inside that was only weakened might not go out later. It's just not worth it. If you're insured, you might consider having a qualified TV technician verify the damage and have your insurance company get you some new sets. |
Repairing Lightning Damaged Tv's
CJ wrote: I have no knowledge about repairing televisions, so I thought I'd ask here, All 3 of my tv's have been damaged by lightning , 2 of them wont even power up and the other one is in black and white now(is a color tv). Just wondering what I could do to repair my tv's? Thanks Like others have said, if you do not have the knowledge, tools and skill for repairing TVs, you would do well to take it to those who have. Having said that, a lightning strike on an electronic device could end up being a career choice for whomever decides to repair it. If you are puzzled by what I meant in the last sentence, you won't be should you attempt to repair them. |
Repairing Lightning Damaged Tv's
wrote in message ... Like others have said, if you do not have the knowledge, tools and skill for repairing TVs, you would do well to take it to those who have. Having said that, a lightning strike on an electronic device could end up being a career choice for whomever decides to repair it. If you are puzzled by what I meant in the last sentence, you won't be should you attempt to repair them. It could just as easily be a blown fuse and a shorted diode in the bridge. We fix a lot more of them in a few minutes than get scrapped for excessive damage. Here in North Florida we see lots of lightning damage, more than in most parts of the country. Certainly many get damaged severly, but it is much more common to have minor damage in the PS. Leonard |
Repairing Lightning Damaged Tv's
"CJ" bravely wrote to "All" (12 Jun 04 21:32:33)
--- on the heady topic of "Repairing Lightning Damaged Tv's" Typically, lightning damage tends to be limited to the antenna connection, tuner, and of course the AC line, ergo the power supply circuits. However, high voltage electricity can arc anywhere that forms the physically shortest path and thus damage can be done just about anywhere in a circuit. Your 2 tv's that won't power up may be the easiest to repair because the power supply may have stopped the lightning surge before it got any further into the circuit. The tv with colour missing may just be more the difficult one to fix. However, with lightning one can never really say for sure because even if a tv seems to function properly after being repaired it may fail again within a day, week, or month. Insurance companies know this and tend to write off equipment which is hit by lightning right off. What happens is that the lightning surge tends to stress semiconductor junctions by charging them beyond their rated voltage and causes them to breakdown. This breakdown current tends to cause localized ionization of the semiconductor material and results in either a permanent short circuit or a latent leakage path. The shorted junctions will of course cause an obvious malfunction. However, the leakage paths will typically worsen over time until they enventually short out too causing a new failure. For these reasons it makes more economical sense to dump a tv that was struck by lightning surge and buy a new one, basically to avoid the hassle. But insurance companies are usually good in paying for this, no? A*s*i*m*o*v CJ From: (CJ) CJ I have no knowledge about repairing televisions, so I thought I'd ask CJ here, All 3 of my tv's have been damaged by lightning , 2 of them wont CJ even power up and the other one is in black and white now(is a color CJ tv). Just wondering what I could do to repair my tv's? Thanks .... Batteries not included. |
Repairing Lightning Damaged Tv's
Oog. Sorry to hear about that... did all of them get damaged at once? If
you live in an area frequented by lightning, the best thing to do is unplug the sets in advance. That's the best surge protection there is, and it's free. It should be noted that power surge suppressors are designed to suppress unsustained power spikes only. They are completely useless at protecting equipment from direct and indirect lightning hits due to the sheer amount of energy that a lightning bolt has. Lightning will exceed the joule rating of even the best surge suppressor. The advice to unplug equipment from electrical outlets and telephone connections during a lightning storm, as advised by Mr. McCullar, is the best way to prevent lightning damage. As for the original poster, there isn't much that can be done to repair lightning damaged equipment if you don't have the training, experience, appropriate service documentation, and the repair equipment. As advised before, it is recommended that the damaged sets be taken to a repair professional. - Reinhart |
Repairing Lightning Damaged Tv's
Thank You! Very well put. I have been explaining this to people for a long
time, but no one will believe me. I have for years, unplugged my computer with any sign of lightning, even if I don't see any, and I know a storm is moving in, I will unplug it. Phone cord and all! And another point on it to is, even if the storms are miles away, you can still get a surge that can damage the device. It don't take much. I have seen it many times when I repaired electronics a long time ago. People need to realize that these devices are very sensitive to electrical problems in the home, including storms. I usually tell people that a surge protector is just good enough to get the device shut down, in the even that a sudden storm comes up. They are also good for the everyday use, to insure that you are protected. Don't get me wrong. I am not saying that you should not use one on any electrical device, but you should not rely on it during a storm or any type of an unsure power situation. Rick It should be noted that power surge suppressors are designed to suppress unsustained power spikes only. They are completely useless at protecting equipment from direct and indirect lightning hits due to the sheer amount of energy that a lightning bolt has. Lightning will exceed the joule rating of even the best surge suppressor. The advice to unplug equipment from electrical outlets and telephone connections during a lightning storm, as advised by Mr. McCullar, is the best way to prevent lightning damage. - Reinhart |
Repairing Lightning Damaged Tv's
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Repairing Lightning Damaged Tv's
The sheer amount of energy from a direct lightning strike is
no where near the levels that myths portray. It is normal and usual to protect electronics from direct strikes without damage. Empire State Building would have 25 direct strikes to TV and FM radio equipment every year without damage. WTC was 40 times per year. The concept were well proven since the 1930s and yet still little understood by many in the 2000s. We still build new buildings as if the transistor did not exist. Earthing - and not some overhyped plug-in protectors - is protection. How earthing is installed and how incoming utilities connect to earthing defines effectiveness of protection. Since most homes directly connect appliances to lines highest on poles, then that is a direct lightning strike - if the incoming transient is not earthed before entering the building. Without upgraded earth ground and 'whole house' protector, then the homeowner is only inviting damage to occur when asleep, when not home, or when appliance is off. Even worse, the plug-in protector can provide a direct strike with more destructive paths through the appliance. Damage occurs because lightning finds earth ground, destructively, through the appliance. A long list of other appliances that cannot be protected by unplugging - GFCI in kitchen and bathroom, dimmer switches, clock radio, dishwasher, alarm system, smoke detectors, microwave oven, portable phone base station, etc. What protects all them? Some comments from those who first learned effective protection and are professionals in this industry: http://www.harvardrepeater.org/news/lightning.html Well I assert, from personal and broadcast experience spanning 30 years, that you can design a system that will handle *direct lightning strikes* on a routine basis. It takes some planning and careful layout, but it's not hard, nor is it overly expensive. At WXIA-TV, my other job, we take direct lightning strikes nearly every time there's a thunderstorm. Our downtime from such strikes is almost non-existant. The last time we went down from a strike, it was due to a strike on the power company's lines knocking *them* out, ... Since my disasterous strike, I've been campaigning vigorously to educate amateurs that you *can* avoid damage from direct strikes. The belief that there's no protection from direct strike damage is *myth*. ... The keys to effective lightning protection are surprisingly simple, and surprisingly less than obvious. Of course you *must* have a single point ground system that eliminates all ground loops. And you must present a low *impedance* path for the energy to go. That's most generally a low *inductance* path rather than just a low ohm DC path. http://www.telebyteusa.com/primer/ch6.htm See Section 6.4: Conceptually, lightning protection devices are switches to ground. Once a threatening surge is detected, a lightning protection device grounds the incoming signal connection point of the equipment being protected. Thus, redirecting the threatening surge on a path-of-least resistance (impedance) to ground where it is absorbed. http://www.ipclp.com/html/aud_ho_faq.html A properly installed lightning protection system intercepts the lightning bolt between cloud and earth and harmlessly conducts it to ground without damage. Yes, in addition to the lightning protection system consisting of air terminals, conductor cables, clamps, fasteners, 10 foot grounds, etc., a secondary lightning suppressor is installed on your electric service entrance panel to prevent current fluctuations (called lightning surges) during a thunderstorm. The 'whole house' protector can be purchased even in Home Depot for less than $50. That is about $1 per protected appliance for effective protection. Compare that to $10 or $50 for the ineffective plug-in protector that also does not claim to protect from the typically destructive surge. Notice the tens of times more money for protectors that don't even claim to protect. Notice the one component always required in every direct strike protection system: single point earth ground. Since ineffective and grossly overpriced plug-in protectors don't even claim to provide effective protection, then ineffective protectors also avoid discussing the most critical part of a protection system - the single point earth ground. No earth ground means no effective protection. BTW if indirect strikes are so destructive, then any nearby strike would destroy the so sensitive RF transistor on every car and handheld radio. In reality, the nearby strike is really a direct strike. Just that the path of electricity was not fully understood. Why might lightning strike that tree? Because it is a path to better conductive earth using buried utilities entering the house, through household appliances, to earth ground on other side of building. Again, protection is about earthing which too many fail to learn - and then assume no protection is possible. Protection from the direct strike is so routine since before WWII that damage from lightning is now considered a human failure. Does your telco disconnect their $multi-million switching computer from overhead wires all over town during every thunderstorm? Of course not. Effective protection has been that well understood since before WWII. Even at the telco switching computer: surge protector is only as effective as its earth ground. Early 1900 ham radio operators would disconnect their antenna, put the antenna lead inside a mason jar, and still suffer damage. Damage stopped when that antenna lead was earthed. Protection only as effective as the earth ground. Even a human disconnecting appliance is less reliable. LASERandDVDfan wrote: It should be noted that power surge suppressors are designed to suppress unsustained power spikes only. They are completely useless at protecting equipment from direct and indirect lightning hits due to the sheer amount of energy that a lightning bolt has. Lightning will exceed the joule rating of even the best surge suppressor. The advice to unplug equipment from electrical outlets and telephone connections during a lightning storm, as advised by Mr. McCullar, is the best way to prevent lightning damage. As for the original poster, there isn't much that can be done to repair lightning damaged equipment if you don't have the training, experience, appropriate service documentation, and the repair equipment. As advised before, it is recommended that the damaged sets be taken to a repair professional. - Reinhart |
Repairing Lightning Damaged Tv's
The sheer amount of energy from a direct lightning strike is no where near the levels that myths portray. It is normal and usual to protect electronics from direct strikes without damage. Thanks to a little thing called the lightning rod invented well before the 20th Century. Grounding, or earthing as you've put it, is a simple way of directing lightning to ground and safely away from anything that could be damaged as you already know. Without grounding, as you've said, the lightning would simply find its path to ground through the electronics. The antenna towers may also double as lightning rods that provide a path to ground to protect not only the transmission equipment, but the entire building as well. But my comment is merely pointing out the misconception by the general public that home power surge suppressors are effective against lightning strikes. They are not effective against that and anyone trusting a surge suppressor over effective grounding, as you've pointed out and I never mentioned, or disconnection of devices from the mains deserves to get their equipment damaged after a storm. - Reinhart |
Repairing Lightning Damaged Tv's
"Ricky Eck" bravely wrote to "All" (14 Jun 04 02:05:25)
--- on the heady topic of " Repairing Lightning Damaged Tv's" RE From: "Ricky Eck" RE [,,,] RE People need to realize that these devices are very sensitive to RE electrical problems in the home, including storms. I usually tell RE people that a surge protector is just good enough to get the device RE shut down, in the even that a sudden storm comes up. They are also RE good for the everyday use, to insure that you are protected. Don't get RE me wrong. I am not saying that you should not use one on any RE electrical device, but you should not rely on it during a storm or any RE type of an unsure power situation. Some years ago we had a rash of storms with a number of direct hits in the neighborhood. One home across the street had a hit on their pole pig and everything electric in the home was destroyed. In the days that followed the electric utility made repairs and installed fat hockey puck size arrestors between the distribution line and ground on every pole pig in the neighborhood. How effective is their protection with a direct lightning strike? Should they be replaced after a hit? A*s*i*m*o*v .... Over a hundred billion electrons were used in crafting this tagline. |
Repairing Lightning Damaged Tv's
Actually those are not as uncommon as some people think. Line "Surge
Protectors" from the electric company can be purchased. It is supposed to work better then ones in your home. This is according to the electric company. However, as I stated before, I would be skeptical on it. I have not researched it too much, and I don't know if they come with a guarantee of your equipment if something did fail. I would think that there is someone out there that works for the power company, that can give us some info on these protectors. I too would be curious if they are damaged after a surge of lightning. I would also like to find out if they protect against the imperfections in the electrical grids. Meaning when the power changes in voltages. I still stick to my methods of unplugging said devices when storms approach. Remember that what we have here are man made devices, and said man made devices, is why we have this message group. Mainly because they easily break. And said man made devices is what keeps many of those on this board, in business. So, if you want to support your fellow repairman, keep 'em plugged in..:) I am sure there will be a lot of happy repairman out there. Just remember, if you do need to take it to a repairman, take it to a small business man, not a major chain. The major shop's money just ends up in some rich man's hands. Money spent at your local business man's shop, will help feed his family. Oh, to answer your "?"...:) I don't know. Maybe there is an electrician with the power company that can answer this "?". "Asimov" wrote in message ... Some years ago we had a rash of storms with a number of direct hits in the neighborhood. One home across the street had a hit on their pole pig and everything electric in the home was destroyed. In the days that followed the electric utility made repairs and installed fat hockey puck size arrestors between the distribution line and ground on every pole pig in the neighborhood. How effective is their protection with a direct lightning strike? Should they be replaced after a hit? A*s*i*m*o*v ... Over a hundred billion electrons were used in crafting this tagline. |
Repairing Lightning Damaged Tv's
The protector is not protection. A protector is only a
temporary connection from incoming wire to protection - earth ground. Ineffective plug-in protector must get the naive to misunderstand. To use word association to assume a protector and protection are same thing. Protector is only effective when it connects 'less than 10 foot' to protection - earth ground. No earth ground, then no effective protection. The 'whole house' protector is only called secondary protection. Primary protection is provided by AC electric utility. A homeowner is advised to make a visual inspection of that utility provided protection. Examples of missing primary protection are demonstrated: http://www.tvtower.com/fpl.html And rules for earthing: http://www.tvtower.com/grounding_and_bonding.html Protection being only as effective as the earth ground. Protector only required when the incoming utility cannot be hardwired directly to earth. Protector only connects incoming wire to earth ground during a destructive transient. LASERandDVDfan wrote: Thanks to a little thing called the lightning rod invented well before the 20th Century. Grounding, or earthing as you've put it, is a simple way of directing lightning to ground and safely away from anything that could be damaged as you already know. Without grounding, as you've said, the lightning would simply find its path to ground through the electronics. The antenna towers may also double as lightning rods that provide a path to ground to protect not only the transmission equipment, but the entire building as well. But my comment is merely pointing out the misconception by the general public that home power surge suppressors are effective against lightning strikes. They are not effective against that and anyone trusting a surge suppressor over effective grounding, as you've pointed out and I never mentioned, or disconnection of devices from the mains deserves to get their equipment damaged after a storm. - Reinhart |
Repairing Lightning Damaged Tv's
How often does your 120 VAC exceed 330 volts? 330 volts is
a number even printed on plug-in protector boxes. If AC line imperfections were occurring that high with any frequency, then you were replacing every dimmer switch, clock radio, AC powered smoke detector, and major household appliances frequently. Those 330 volt transients typically don't exist from the utility. Therefore the protector remains inert - does nothing - sees no such imperfections. AC line imperfections are less voltage. Expensive electronic equipment contains internal protection that makes 'imperfections' even up to 600 volts irrelevant. Appliances already contain internal protection. Protection that assumes the major and destructive transients will be earthed before entering a building. The transient that does exist typically once every eight years is a common mode transient on AC electric that 1) occurs quickly (in microseconds), 2) requires a complete circuit to earth ground in order to do appliance damage (which is why phone appliances are so often damaged), and 3) that a plug-in protector does not even claim to protect from. Protectors are effective when they make the 'less than 10 foot' connection to earth ground. Called 'whole house' type protectors. That is what a utility installed protector does IF your building has been wired to post 1990 code requirements for earthing. A utility typically does not even check that your earthing exists. Household earthing being the homeowner's responsibility; not utilities. No earth ground means no effective protection even from that utility provided protector that typically costs a very expensive $5 per month. Of course utilities can charge so much because so many homeowners spend much more money on ineffective plug-in protectors. That utility provided protector costs many times less per protected appliance and does more (assuming the post 1990 earthing exists). But the best protection for the money is a homeowner installed 'whole house' protector installed in breaker box and with the necessary earthing connections. Home Depot even sells the Intermatic IG1240RC. Many others are available. Unplugging is unreliable. The human is typically available and awake less than 1/3rd of each day. But effective 'whole house' protection means no need to unplug; needs no unreliable human to provide protection. 'Whole house' protector is always there; doing what existing internal appliance protection requires to not be overwhelmed. Bottom line: a protector is only as effective as its earth ground. Something that plug-in protectors fear you might learn and avoid mentioning. Ricky Eck wrote: Actually those are not as uncommon as some people think. Line "Surge Protectors" from the electric company can be purchased. It is supposed to work better then ones in your home. This is according to the electric company. However, as I stated before, I would be skeptical on it. I have not researched it too much, and I don't know if they come with a guarantee of your equipment if something did fail. I would think that there is someone out there that works for the power company, that can give us some info on these protectors. I too would be curious if they are damaged after a surge of lightning. I would also like to find out if they protect against the imperfections in the electrical grids. Meaning when the power changes in voltages. I still stick to my methods of unplugging said devices when storms approach. Remember that what we have here are man made devices, and said man made devices, is why we have this message group. Mainly because they easily break. And said man made devices is what keeps many of those on this board, in business. So, if you want to support your fellow repairman, keep 'em plugged in..:) I am sure there will be a lot of happy repairman out there. Just remember, if you do need to take it to a repairman, take it to a small business man, not a major chain. The major shop's money just ends up in some rich man's hands. Money spent at your local business man's shop, will help feed his family. Oh, to answer your "?"...:) I don't know. Maybe there is an electrician with the power company that can answer this "?". |
Repairing Lightning Damaged Tv's
w_tom wrote: How often does your 120 VAC exceed 330 volts? 330 volts is a number even printed on plug-in protector boxes. If AC line imperfections were occurring that high with any frequency, then you were replacing every dimmer switch, clock radio, AC powered smoke detector, and major household appliances frequently. Those 330 volt transients typically don't exist from the utility. Therefore the protector remains inert - does nothing - sees no such imperfections. AC line imperfections are less voltage. Expensive electronic equipment contains internal protection that makes 'imperfections' even up to 600 volts irrelevant. Appliances already contain internal protection. Protection that assumes the major and destructive transients will be earthed before entering a building. The transient that does exist typically once every eight years is a common mode transient on AC electric that 1) occurs quickly (in microseconds), 2) requires a complete circuit to earth ground in order to do appliance damage (which is why phone appliances are so often damaged), and 3) that a plug-in protector does not even claim to protect from. Protectors are effective when they make the 'less than 10 foot' connection to earth ground. Called 'whole house' type protectors. That is what a utility installed protector does IF your building has been wired to post 1990 code requirements for earthing. A utility typically does not even check that your earthing exists. Household earthing being the homeowner's responsibility; not utilities. No earth ground means no effective protection even from that utility provided protector that typically costs a very expensive $5 per month. Of course utilities can charge so much because so many homeowners spend much more money on ineffective plug-in protectors. That utility provided protector costs many times less per protected appliance and does more (assuming the post 1990 earthing exists). But the best protection for the money is a homeowner installed 'whole house' protector installed in breaker box and with the necessary earthing connections. Home Depot even sells the Intermatic IG1240RC. Many others are available. Unplugging is unreliable. The human is typically available and awake less than 1/3rd of each day. But effective 'whole house' protection means no need to unplug; needs no unreliable human to provide protection. 'Whole house' protector is always there; doing what existing internal appliance protection requires to not be overwhelmed. Unplugging is unreliable even when the human is available and paying attention. I recently lost an expensive stereo and TV due to a direct hit about 20 feet from my cottage. The equipment was unplugged prior to the strike, but I didn't think to disconnect the speaker cables and antenna... An extension cord lying disconnected on the ground outside writhed like a snake and now has neat holes burnt through the outer casing at exactly 27" intervals. I doubt protection is possible under those circumstances - but I did catch 3 nice sized Northern Pike for dinner with my bare hands as they floated past the dock, stunned :-) Bottom line: a protector is only as effective as its earth ground. Something that plug-in protectors fear you might learn and avoid mentioning. Ricky Eck wrote: Actually those are not as uncommon as some people think. Line "Surge Protectors" from the electric company can be purchased. It is supposed to work better then ones in your home. This is according to the electric company. However, as I stated before, I would be skeptical on it. I have not researched it too much, and I don't know if they come with a guarantee of your equipment if something did fail. I would think that there is someone out there that works for the power company, that can give us some info on these protectors. I too would be curious if they are damaged after a surge of lightning. I would also like to find out if they protect against the imperfections in the electrical grids. Meaning when the power changes in voltages. I still stick to my methods of unplugging said devices when storms approach. Remember that what we have here are man made devices, and said man made devices, is why we have this message group. Mainly because they easily break. And said man made devices is what keeps many of those on this board, in business. So, if you want to support your fellow repairman, keep 'em plugged in..:) I am sure there will be a lot of happy repairman out there. Just remember, if you do need to take it to a repairman, take it to a small business man, not a major chain. The major shop's money just ends up in some rich man's hands. Money spent at your local business man's shop, will help feed his family. Oh, to answer your "?"...:) I don't know. Maybe there is an electrician with the power company that can answer this "?". |
Repairing Lightning Damaged Tv's
Protection is always possible. Ham radio operators in the
early 1900s would suffer damage. They disconnected the antenna. Still suffered damage. They placed antenna lead into a mason jar. Still suffered damage. They earthing the incoming antenna wire. Damage stopped happening. Damage occurs whenever the direct strike finds a path to earth ground inside building via the appliance. Incoming on antenna wire. Outgoing via speaker wires to earth ground via concrete floor or by being draped on adjacent baseboard heat. Your situation may vary. But this we have always understood. Protection works when all incoming wires are earthed to a single point ground. That means all utility wires must enter building at same location. That means the single point earth ground must be the best earthing for that building. Your phone already makes that earthing connection using a 'whole house' protector inside the premise interface box. Phone cannot work if earthed directly. So a protector makes the temporary earthing connection; earthing wire only during a surge. Your cable needs no protector. But cable needs connection to protection. Cable connects directly to the single point earth ground before entering building to earth incoming transients. Earthing is why effective protection works. The single point earth ground. And yet 30 years after the transistor is ubiquitous, we still don't build new buildings as if the transistor exists. AC electric routinely enters without connection to earth ground. Again, this utility requires a 'whole house' protector such as from Home Depot (Intermatic IG1240RC). And - of course - your building's single point earth ground may not yet exist. Older buildings often had no single point ground. The building owner may need to upgrade or exceed earthing requirements of the current National Electrical Code. No earth ground means no effective protection. The naive assume nothing can protect from lightning even though it is done annually in virtually every town. Remember the lessons from early ham radio operators. Earthing is still necessary to avoid damage. Protection is only as effective as its earth ground. Sunny wrote: w_tom wrote: ... Protectors are effective when they make the 'less than 10 foot' connection to earth ground. Called 'whole house' type protectors. That is what a utility installed protector does IF your building has been wired to post 1990 code requirements for earthing. A utility typically does not even check that your earthing exists. Household earthing being the homeowner's responsibility; not utilities. No earth ground means no effective protection even from that utility provided protector that typically costs a very expensive $5 per month. ... Bottom line: a protector is only as effective as its earth ground. Something that plug-in protectors fear you might learn and avoid mentioning. Unplugging is unreliable even when the human is available and paying attention. I recently lost an expensive stereo and TV due to a direct hit about 20 feet from my cottage. The equipment was unplugged prior to the strike, but I didn't think to disconnect the speaker cables and antenna... An extension cord lying disconnected on the ground outside writhed like a snake and now has neat holes burnt through the outer casing at exactly 27" intervals. I doubt protection is possible under those circumstances - but I did catch 3 nice sized Northern Pike for dinner with my bare hands as they floated past the dock, stunned :-) |
Repairing Lightning Damaged Tv's
w_tom wrote: Protection is always possible. Ham radio operators in the early 1900s would suffer damage. They disconnected the antenna. Still suffered damage. They placed antenna lead into a mason jar. Still suffered damage. They earthing the incoming antenna wire. Damage stopped happening. Damage occurs whenever the direct strike finds a path to earth ground inside building via the appliance. Incoming on antenna wire. Outgoing via speaker wires to earth ground via concrete floor or by being draped on adjacent baseboard heat. Your situation may vary. I personally installed the electric service at my cottage 20 years ago, in accordance with all Canadian electrical codes in effect at the time. IIRC, earthing involved banging two 8' rods into the ground several feet apart and connecting them to the neutral bus-bar inside the fuse panel, and also running a cable from the same bus-bar to the cold water plumbing. The phone company installed the phone service, which enters the building beside the electric meter, but I don't know if/how they effected earthing. The only other incoming wire is from the TV antenna, on the opposite side of the building, which currently has no earthing. I would be greatful if you could explain, in laymans terms, what further steps I could take to protect my cottage electrical equipment from lightning strikes - since unplugging doesn't work. I have no reason to doubt your assertion that protection is always possible, but I am having some difficulty translating your advice into practice. Thanks, Sunny But this we have always understood. Protection works when all incoming wires are earthed to a single point ground. That means all utility wires must enter building at same location. That means the single point earth ground must be the best earthing for that building. Your phone already makes that earthing connection using a 'whole house' protector inside the premise interface box. Phone cannot work if earthed directly. So a protector makes the temporary earthing connection; earthing wire only during a surge. Your cable needs no protector. But cable needs connection to protection. Cable connects directly to the single point earth ground before entering building to earth incoming transients. Earthing is why effective protection works. The single point earth ground. And yet 30 years after the transistor is ubiquitous, we still don't build new buildings as if the transistor exists. AC electric routinely enters without connection to earth ground. Again, this utility requires a 'whole house' protector such as from Home Depot (Intermatic IG1240RC). And - of course - your building's single point earth ground may not yet exist. Older buildings often had no single point ground. The building owner may need to upgrade or exceed earthing requirements of the current National Electrical Code. No earth ground means no effective protection. The naive assume nothing can protect from lightning even though it is done annually in virtually every town. Remember the lessons from early ham radio operators. Earthing is still necessary to avoid damage. Protection is only as effective as its earth ground. Sunny wrote: w_tom wrote: ... Protectors are effective when they make the 'less than 10 foot' connection to earth ground. Called 'whole house' type protectors. That is what a utility installed protector does IF your building has been wired to post 1990 code requirements for earthing. A utility typically does not even check that your earthing exists. Household earthing being the homeowner's responsibility; not utilities. No earth ground means no effective protection even from that utility provided protector that typically costs a very expensive $5 per month. ... Bottom line: a protector is only as effective as its earth ground. Something that plug-in protectors fear you might learn and avoid mentioning. Unplugging is unreliable even when the human is available and paying attention. I recently lost an expensive stereo and TV due to a direct hit about 20 feet from my cottage. The equipment was unplugged prior to the strike, but I didn't think to disconnect the speaker cables and antenna... An extension cord lying disconnected on the ground outside writhed like a snake and now has neat holes burnt through the outer casing at exactly 27" intervals. I doubt protection is possible under those circumstances - but I did catch 3 nice sized Northern Pike for dinner with my bare hands as they floated past the dock, stunned :-) |
Repairing Lightning Damaged Tv's
Protection starts with the underlying geology. Best is a
monolithic soil of clay or loam that is damp. Worst is sand or gravel. Also bad would be two different types of soil where the more electrically conductive vein is far from the single point ground. Example: they had a bathroom wall struck twice by lightning. They installed lightning rods. The bathroom wall was struck a third time. Lightning rods were earthed in sand. Bathroom plumbing made a better connection to deeper limestone. One poster in the Perennes once said he had to sink a 150 foot ground rod to get through glacier tailings and into more conductive soil. A rather extreme example that demonstrates the point. Establish the single point earth ground. For most, two ground rods driven well below the frost line and separated by a distance equivalent to their length is sufficient (Rods closer tend to act as if they were the same rod). Idea is to make this the best electrical ground on the property. All incoming utilities first connect to this single point ground either by direct wire connection or via a surge protector. Unfortunately, your antenna violates the principle. But there are alternative solutions. Three examples - the bad, ugly, and good (left to right) - are provided in figure 2. Concept demonstrated in figure 1. Halo ground that connects your earth grounds together. This could be a buried bare 4 AWG ground wire that interconnects AC electric ground to TV antenna ground. That buried bare wire makes all grounds equipotential as well as enhances the connection of earth ground to earth: http://www.cinergy.com/surge/ttip08.htm A US government publication further discusses the single point principle: http://www.pueblo.gsa.gov/cic_text/h...ontractors.htm Equipotential means earth beneath cottage appears to be the same voltage no matter how massive the direct strike. We can install a great earth ground. But that may not be sufficient. So we surround the house with a halo ground or Ufer ground to also make earth beneath building equipotential. Homes built to contain transistors have a halo or Ufer ground installed when footing are pours - plans for good earthing must be started that early. This principle avoids complications created by varying earths. A complication that most homes new not worry about. But a halo or Ufer ground should be installed in all new construction because it is so cheap and so effective. Now that we have established a good earth ground, we are now ready to make connection to that ground. Every wire entering the building must connect that that single point ground. Ground wire connection (ie from neutral bus bar) must be short, direct, and independent. IOW (short) it must be less than ten feet. It (direct) must have no sharp bends; no splices. (Even 90 turns and lead solder joints on copper water pipes violate good connection requirements). It (independent) must be separated from all other non-earthing wires and must not connect to any other earthing wire until they all meet at the single point ground. Idea is to make that earthing wire low impedance; not just low resistance. For example, 90 degree bends could add a mircohenries to wire inductance. For earthing, that would result in a substantial increase in wire impedance. Using numbers: that earthing wire might have less than .1 ohms resistance. But it might also have as much as 4 ohms impedance. Any increase in earthing wire impedance means a surge may seek other and destructive paths to earth ground inside the building. An earthing wire from bus bar straight through foundation to a point just above soil would be superior to an earth ground that routes up over top of foundation (through 2x10 or rim board) and back down to earth. Two other AC electric wires have also entered the building and cannot be earthed - also called hot wires. These are the most common source of surge damage especially to phone appliances that use AC electric - answering machine, computer modem, portable phone base station. The 'whole house' protector must connect from each wire to that bus bar. One minimally sized example sold in Home Depot is Intermatic IG1240RC. Others have been listed in newsgroup misc.rural as "telephone wire/lightning strikes" on 30 Sept 2003: http://tinyurl.com/q6g6 A 'whole house' protector for residential service should be at minimum 1000 joules and 50,000 amps. Some, such as GE's THQLSurge (if I have remembered the name correctly) that is also sold in Lowes, is undersized and overpriced. Square D makes one protector that is undersized AND does not even provide joules in its specs. But in that list is another Square D product that is well designed - more than meets minimum requirements. Telco installs a 'whole house' protector that meets US National Electrical Code requirements: From Article 800.30A: A listed primary protector shall be provided on each circuit run partly or entirely in aerial wire or aerial cable not confined within the block containing the building served so as to be exposed to accidental contact with electric light or power conductor operating at over 300 volts to ground. In addition, where there exists a lightning exposure, each interbuilding circuit on a premise shall be protected by a listed primary protector at each end of the interbuilding circuit. Article 800.30B Location. The primary protector shall be located in, on, or immediately adjacent to the structure or building served and as close as practical to the point of entrance. Article 800.31 The primary protector shall consist of an arrester connected between each line conducor and ground in an appropriate mounting. Primary protector terminals shall be marked to indicate line and ground as applicable. NID that contains telephone 'whole house' protector is: http://www.alarmsuperstore.com/bw/bw%20connectors.htm or http://www.bass-home.com/gotoproduct.cfm?item=91598 A 14 AWG wire connects from that box to the single point ground. Again, it should meet these criteria rather than look neat: be short, direct, and independent. Too many telco installers want to square off the wire or neatly ty-wrap a ground wire to other cables. Wrong. That 14 AWG (more often is 12 AWG) wire must run independently and directly to the same single point ground used by AC electric. Both grounds meet at the earthing rod - the single point ground. Every incoming wire - all three AC electric, both telephone wires, and shield of any incoming coax cable from satellite dish - are earthed to same earth ground. As noted earlier, that antenna will require special attention. Now lets discuss induced transients. Lightning strikes the TV antenna seeking earth ground. Path will be destructive via household wires. And not necessary just through TV and AC electric to earth ground. That antenna wire may be bundled with other wires. Therefore that antenna wire induces transients on other wires or may even arc into those other wires. Same problem is also created by plug-in protectors. Lets say a plug-in protector is earthing the transient. IOW it is shunting a transient into the AC electric safety ground wire. But that safety ground wire is bundled with other wires. Now a transient is induced onto those other wires. Just another example of why plug-in protectors are not effective and can even contribute to surge damage. Idea is to earth a transient before it can enter the building. Not just earth anywhere, but earth less than 10 feet to a single point. Campers demonstrate the principle. They were sleeping nearby a tree that was struck. Lightning strikes tree to obtain earth borne charges some kilometers beyond those boys. Some were sleeping perpendicular to that tree and were not hurt. Any boy who was sleeping pointed towards that tree had electricity rise up into his feet, pass through his body, then exit via his head. Body is more conductive than earth. Lightning will find every conductive path to those earth borne charges some kilometers away. This is also why multiple earth grounds on a building can cause lightning to find the other earth ground, destructively, via the house. When lightning is striking, stand with both feet together - the single point ground. Building uses same concept to not have appliances damaged. Incoming transients also applies to buried wires. This industry professional (another source of protectors) demonstrates two structures - each with their own single point earth ground AND both single point grounds interconnected. Buried phone line is also carrying a destructive transient. Phone line is earthed at building's earth ground before entering because even buried wires carry destructive transients: http://www.erico.com/public/library/...es/tncr002.pdf 'Whole house' protectors are only secondary protection. Primary protection is provided by the utility at transformer. But that primary protector may need be inspected. Some pictures of what to look for: http://www.tvtower.com/fpl.html And rules for earthing: http://www.tvtower.com/grounding_and_bonding.html Protectors are only a simple science of protection. The art is in the earthing. More about earthing was discussed previously in two threads in the newsgroup misc.rural: Storm and Lightning damage in the country 28 Jul 2002 Lightning Nightmares!! 10 Aug 2002 http://tinyurl.com/ghgv and http://tinyurl.com/ghgm Should you wish to learn more, Polyphaser (another manufacturer of 'real world' protectors) provides application notes such as this one about single point ground: http://www.polyphaser.com/ppc_PEN1002.asp and others: http://www.polyphaser.com/ppc_technical.asp http://www.polyphaser.com/ppc_pen_home.asp Additional information in some MTL Surge Technology app notes at: http://www.mtlsurgetechnologies.com/...tans/index.htm Bottom line is this: a surge protector is not protection. A surge protector is only as effective as its earth ground. Notice no technical references to companies that sell ineffective protection such as APC, Panamax, and Tripplite - and other plug-in manufacturers so often hyped by myth. What do they avidly avoid discussing to sell their ineffective products? Earth ground. No earth ground means no effective protection. Sunny wrote: I personally installed the electric service at my cottage 20 years ago, in accordance with all Canadian electrical codes in effect at the time. IIRC, earthing involved banging two 8' rods into the ground several feet apart and connecting them to the neutral bus-bar inside the fuse panel, and also running a cable from the same bus-bar to the cold water plumbing. The phone company installed the phone service, which enters the building beside the electric meter, but I don't know if/how they effected earthing. The only other incoming wire is from the TV antenna, on the opposite side of the building, which currently has no earthing. I would be greatful if you could explain, in laymans terms, what further steps I could take to protect my cottage electrical equipment from lightning strikes - since unplugging doesn't work. I have no reason to doubt your assertion that protection is always possible, but I am having some difficulty translating your advice into practice. Thanks, Sunny |
Repairing Lightning Damaged Tv's
Your incredibly comprehensive and useful reply is very much appreciated!
Thanks, Sunny w_tom wrote: Protection starts with the underlying geology. Best is a monolithic soil of clay or loam that is damp. Worst is sand or gravel. Also bad would be two different types of soil where the more electrically conductive vein is far from the single point ground. Example: they had a bathroom wall struck twice by lightning. They installed lightning rods. The bathroom wall was struck a third time. Lightning rods were earthed in sand. Bathroom plumbing made a better connection to deeper limestone. One poster in the Perennes once said he had to sink a 150 foot ground rod to get through glacier tailings and into more conductive soil. A rather extreme example that demonstrates the point. Establish the single point earth ground. For most, two ground rods driven well below the frost line and separated by a distance equivalent to their length is sufficient (Rods closer tend to act as if they were the same rod). Idea is to make this the best electrical ground on the property. All incoming utilities first connect to this single point ground either by direct wire connection or via a surge protector. Unfortunately, your antenna violates the principle. But there are alternative solutions. Three examples - the bad, ugly, and good (left to right) - are provided in figure 2. Concept demonstrated in figure 1. Halo ground that connects your earth grounds together. This could be a buried bare 4 AWG ground wire that interconnects AC electric ground to TV antenna ground. That buried bare wire makes all grounds equipotential as well as enhances the connection of earth ground to earth: http://www.cinergy.com/surge/ttip08.htm A US government publication further discusses the single point principle: http://www.pueblo.gsa.gov/cic_text/h...ontractors.htm Equipotential means earth beneath cottage appears to be the same voltage no matter how massive the direct strike. We can install a great earth ground. But that may not be sufficient. So we surround the house with a halo ground or Ufer ground to also make earth beneath building equipotential. Homes built to contain transistors have a halo or Ufer ground installed when footing are pours - plans for good earthing must be started that early. This principle avoids complications created by varying earths. A complication that most homes new not worry about. But a halo or Ufer ground should be installed in all new construction because it is so cheap and so effective. Now that we have established a good earth ground, we are now ready to make connection to that ground. Every wire entering the building must connect that that single point ground. Ground wire connection (ie from neutral bus bar) must be short, direct, and independent. IOW (short) it must be less than ten feet. It (direct) must have no sharp bends; no splices. (Even 90 turns and lead solder joints on copper water pipes violate good connection requirements). It (independent) must be separated from all other non-earthing wires and must not connect to any other earthing wire until they all meet at the single point ground. Idea is to make that earthing wire low impedance; not just low resistance. For example, 90 degree bends could add a mircohenries to wire inductance. For earthing, that would result in a substantial increase in wire impedance. Using numbers: that earthing wire might have less than .1 ohms resistance. But it might also have as much as 4 ohms impedance. Any increase in earthing wire impedance means a surge may seek other and destructive paths to earth ground inside the building. An earthing wire from bus bar straight through foundation to a point just above soil would be superior to an earth ground that routes up over top of foundation (through 2x10 or rim board) and back down to earth. Two other AC electric wires have also entered the building and cannot be earthed - also called hot wires. These are the most common source of surge damage especially to phone appliances that use AC electric - answering machine, computer modem, portable phone base station. The 'whole house' protector must connect from each wire to that bus bar. One minimally sized example sold in Home Depot is Intermatic IG1240RC. Others have been listed in newsgroup misc.rural as "telephone wire/lightning strikes" on 30 Sept 2003: http://tinyurl.com/q6g6 A 'whole house' protector for residential service should be at minimum 1000 joules and 50,000 amps. Some, such as GE's THQLSurge (if I have remembered the name correctly) that is also sold in Lowes, is undersized and overpriced. Square D makes one protector that is undersized AND does not even provide joules in its specs. But in that list is another Square D product that is well designed - more than meets minimum requirements. Telco installs a 'whole house' protector that meets US National Electrical Code requirements: From Article 800.30A: A listed primary protector shall be provided on each circuit run partly or entirely in aerial wire or aerial cable not confined within the block containing the building served so as to be exposed to accidental contact with electric light or power conductor operating at over 300 volts to ground. In addition, where there exists a lightning exposure, each interbuilding circuit on a premise shall be protected by a listed primary protector at each end of the interbuilding circuit. Article 800.30B Location. The primary protector shall be located in, on, or immediately adjacent to the structure or building served and as close as practical to the point of entrance. Article 800.31 The primary protector shall consist of an arrester connected between each line conducor and ground in an appropriate mounting. Primary protector terminals shall be marked to indicate line and ground as applicable. NID that contains telephone 'whole house' protector is: http://www.alarmsuperstore.com/bw/bw%20connectors.htm or http://www.bass-home.com/gotoproduct.cfm?item=91598 A 14 AWG wire connects from that box to the single point ground. Again, it should meet these criteria rather than look neat: be short, direct, and independent. Too many telco installers want to square off the wire or neatly ty-wrap a ground wire to other cables. Wrong. That 14 AWG (more often is 12 AWG) wire must run independently and directly to the same single point ground used by AC electric. Both grounds meet at the earthing rod - the single point ground. Every incoming wire - all three AC electric, both telephone wires, and shield of any incoming coax cable from satellite dish - are earthed to same earth ground. As noted earlier, that antenna will require special attention. Now lets discuss induced transients. Lightning strikes the TV antenna seeking earth ground. Path will be destructive via household wires. And not necessary just through TV and AC electric to earth ground. That antenna wire may be bundled with other wires. Therefore that antenna wire induces transients on other wires or may even arc into those other wires. Same problem is also created by plug-in protectors. Lets say a plug-in protector is earthing the transient. IOW it is shunting a transient into the AC electric safety ground wire. But that safety ground wire is bundled with other wires. Now a transient is induced onto those other wires. Just another example of why plug-in protectors are not effective and can even contribute to surge damage. Idea is to earth a transient before it can enter the building. Not just earth anywhere, but earth less than 10 feet to a single point. Campers demonstrate the principle. They were sleeping nearby a tree that was struck. Lightning strikes tree to obtain earth borne charges some kilometers beyond those boys. Some were sleeping perpendicular to that tree and were not hurt. Any boy who was sleeping pointed towards that tree had electricity rise up into his feet, pass through his body, then exit via his head. Body is more conductive than earth. Lightning will find every conductive path to those earth borne charges some kilometers away. This is also why multiple earth grounds on a building can cause lightning to find the other earth ground, destructively, via the house. When lightning is striking, stand with both feet together - the single point ground. Building uses same concept to not have appliances damaged. Incoming transients also applies to buried wires. This industry professional (another source of protectors) demonstrates two structures - each with their own single point earth ground AND both single point grounds interconnected. Buried phone line is also carrying a destructive transient. Phone line is earthed at building's earth ground before entering because even buried wires carry destructive transients: http://www.erico.com/public/library/...es/tncr002.pdf 'Whole house' protectors are only secondary protection. Primary protection is provided by the utility at transformer. But that primary protector may need be inspected. Some pictures of what to look for: http://www.tvtower.com/fpl.html And rules for earthing: http://www.tvtower.com/grounding_and_bonding.html Protectors are only a simple science of protection. The art is in the earthing. More about earthing was discussed previously in two threads in the newsgroup misc.rural: Storm and Lightning damage in the country 28 Jul 2002 Lightning Nightmares!! 10 Aug 2002 http://tinyurl.com/ghgv and http://tinyurl.com/ghgm Should you wish to learn more, Polyphaser (another manufacturer of 'real world' protectors) provides application notes such as this one about single point ground: http://www.polyphaser.com/ppc_PEN1002.asp and others: http://www.polyphaser.com/ppc_technical.asp http://www.polyphaser.com/ppc_pen_home.asp Additional information in some MTL Surge Technology app notes at: http://www.mtlsurgetechnologies.com/...tans/index.htm Bottom line is this: a surge protector is not protection. A surge protector is only as effective as its earth ground. Notice no technical references to companies that sell ineffective protection such as APC, Panamax, and Tripplite - and other plug-in manufacturers so often hyped by myth. What do they avidly avoid discussing to sell their ineffective products? Earth ground. No earth ground means no effective protection. Sunny wrote: I personally installed the electric service at my cottage 20 years ago, in accordance with all Canadian electrical codes in effect at the time. IIRC, earthing involved banging two 8' rods into the ground several feet apart and connecting them to the neutral bus-bar inside the fuse panel, and also running a cable from the same bus-bar to the cold water plumbing. The phone company installed the phone service, which enters the building beside the electric meter, but I don't know if/how they effected earthing. The only other incoming wire is from the TV antenna, on the opposite side of the building, which currently has no earthing. I would be greatful if you could explain, in laymans terms, what further steps I could take to protect my cottage electrical equipment from lightning strikes - since unplugging doesn't work. I have no reason to doubt your assertion that protection is always possible, but I am having some difficulty translating your advice into practice. Thanks, Sunny |
Repairing Lightning Damaged Tv's
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