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#81
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Richard J Kinch" wrote in message . .. As dangerous as this is, is this even possible? All I can say is that here in SE Florida since Hurricane Wilma this week, with 6 million people out of power, with my neighborhood as a sample, there must be about 1 million backfed generators hooked up and running. It is not just commonplace; it is the norm. One neighbor had a (gypsy) electrician install a 4-wire twist-lock socket in his garage specifically for backfeeding through a suicide cord. Just stand in the electrical aisle of Home Depot for 5 minutes. You will see a steady stream of people buying wire and plugs and asking how to make a backfeed connection. The same thing happened on a slightly smaller but still massive scale last year after Hurricanes Jeanne and Frances. I don't recall any reports of utility workers or users being harmed by the practice. There were certainly more people poisoned by carbon monoxide from generators than hurt or killed by electrocution from backfeeding or other misuse. Do you know what a step-down transformer does? It converts 7200 volts to 240 & 120 volts. Do you know what happens when you backfeed 240 volts through it? It puts 7200 volts back into the line. Many areas operate with primary voltages higher than 7200 volts. Do you know how little current it takes to kill you at such a voltage? Very little. It's the same current that it takes to kill you at 120/240 volts. The difference in not in the current requirement, it is in the amount of insulation required to protect you. Your limited knowledge and limited reasoning power are forming dangerous conclusions. Stop doing that. Someone may get killed because of what you are saying. Your limited knowledge is forming incorrect assertions. The amount of current flowing across the heart required to kill you is small and a constant. The voltage necessary to achieve this current varies depending on the contact conditions. Once you exceed the voltage necessary to produce that current across the resistance of the human body over the distance between the contact points, you're toast. Pete C. |
#82
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Backfeed generator through dryer outlet?
JOHN D wrote:
I'm not an electrician but here's my 2 cents. You can't ever let your generator feed back down the power lines. The main breaker must be off and must stay off. It doesn't matter if your generator can't possibly power the whole neighborhood or the whole grid..If people hook up generators to their house wireing, even for a few seconds, without isolating the house from the line,.sooner or later, somewhere, the right set of conditions will exist to electrocute a lineman. You can't take that chance. The main breaker must be off. There must be no chance that anyone will turn the main breaker back on before the generator connection is removed. I can see a lot of ways for this to go wrong. I don't see where there's risk of back feeding through the neutral line any more than there would be if you have a proper generator transfer switch. Does a transfer switch isolate the neutral? I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. |
#83
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Backfeed generator through dryer outlet?
"Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. |
#84
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Backfeed generator through dryer outlet?
According to Pete C. :
I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. I'm sure that a linesman whose been putting in 16 hour days for a week reconnecting lines after a hurricane will appreciate the attitude about booby traps. Secondly, who said it's only linesmen? Last I heard, homeowners don't have such training, and a 4KV+ line lying in the ground isn't biased as to who it bites. Including unwary homeowners. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
#85
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Backfeed generator through dryer outlet?
Wow, there's so much bull here it's almost amazing.
"Pete C." wrote in message ... .... : : There is nothing improper or unsafe about a temporary generator hookup : when done **by a competent person**. " === If that's the basis of your comments, it's silly - these posts aren't about a vague descrition of a "competent" person. Throwing the main breaker" is exactly : what some approved transfer switches do, === No, it is not. They connect to or disconnect power from/to a predetermined path. The main breaker is not "thrown" by the transfer switch. they have two very ordinary : circuit breakers mounted opposite each other and a link bar between the : handles. The only difference between this arrangement and the "turn off : the main and back feed the dryer circuit" temporary connection is the : link bar. === Guess you're making apoint here, but not sure what it is. : : A competent person === Meaningless term again. Vague, not useful or meaningful. You mean a licensed electrician or more from the sound of it. switches off and tags the main breaker before they : even haul out the generator, double checks it again after turning off : the dryer circuit breaker and connecting the "suicide cable", starts the : generator and then finally reviews the main breaker once more before : turning on the dryer circuit breaker to power the panel. === Oh, but they don't notify/chase out the neighborhood kids, pets and others? : : : The fact that the NEC requires generators to be connected : with isolation switches seems to go right over their heads. === No, I haven't seen much evidence of that. Pooly stated comment and not what I think you meant to say. : They apparently think it's ok for them to bypass code : requirements because 'they know what they're doing' and === But, if they "know what they're doing", wouldn't that make them a "competent person"? : neither them, nor someone else trying to use their generator : will ever make a mistake! Pretty arrogant attitude if you : ask me. === Yabut, it sounds just like your attitude earlier in this post. : : The NEC requires double throw transfer switches or approved equivalents : for permanent generator installations. A temporary hookup of a portable : generator in an emergency situation is not within the scope of the NEC. : Nothing "arrogant" about not not following code that is not applicable. === True, but ... there are a couple sections of the NEC you're apparently not familiar with, plus you totally ignore any local codes in that statement. : : : Bottom line - if you're going to use a generator to energize : your home do it right! Use an isolation switch! The code : requires it for the safety of everyone involved! === No, use a Transfer Switch. An "isolation" switch in this context is meaningless. : : It is asinine to claim that you should always install a transfer switch : in order to connect a generator, === No, it is assinine to make the ego-centric statements you've made, though. Something tells me you only -think- you are a "competent person". Else you wouldn't try to make most of these statements. transfer switches only make sense in : permanent installations. === No, they make a tremendous amount of sense. They make it easy, quick to do, and about as close to foolproof as you can make the situation. If Mom's the only one home and the pipes are freezing, all she has to do is start the generator by pusing the button, then turn on the power with the transfer switch. We'd be up and running before your "competent" guy even found his cordsets. Our situation isn't quite as neat: Here, you first have to roll the generator out of the garage and over to the porch, about 5 feet from the garage door, and plug it into the house first. Quite a hardship, but ... it's reliable and works. Ice Storm Survivor Pop : : Pete C. |
#86
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Backfeed generator through dryer outlet?
"Spud" wrote in message ... "Steve Kraus" wrote in message nk.net... Me wrote: Your thinking is just plain wrong..... No, I think I'm on solid ground when I say that a load measuring in many megaWatts, maybe hundreds of megaWatts depending on the area of the power outage that I am downstream of, is essentially the same as shorting the generator output to ground. What about the downed power line your neighbors, and you. http://www.google.com/ In the aftermath of a disaster there are circumstances that circumvent conventional safety procedures. The utility companies rely heavily on independent construction firms to quickly restore utility lines. Private contractor employees are sometimes less familiars with the territory and the established utility company procedures. On top of everything else there is the stress caused by working long hours in inclement conditions and the pressure to restore power to thousands of customers some of whom are in dire need. A line crew was dispatched at night to restore power to a small restaurant in a mountainous area. The restaurant was served by a 3-phase, 12.47-kV, tapline, three spans in length. "The crew found that tree limbs had fallen into a corner pole (one span from the restaurant) short-circuiting the line and blowing the fuses back at the tap pole. They also discovered that the restaurant was using a generator to maintain service." The foreman confirmed that the main breaker at the restaurant was open, isolating the utility service. The crew tested and grounded the line a the tap pole and began repairs. When one lineman climbed the corner pole to remove limbs, he discovered that the jumpers and connectors were damaged and decided to replace them. "When he removed the jumpers, he was positioned in such a way that he was in contact with the under grounded portion of the line," continues Drew. For some reason, the restaurant owner was checking the generator and inadvertently closed the main breaker, backing power through the transformer bank and energizing the line up to the open jumpers. The lineman received a severe shock and died. 8/29/2005 As the number of personal electric generators grows, so does the threat of injury to utility workers and generator operators. If you connect a generator to your electrical panel without isolating it, it 's simply a disaster waiting to happen. A generator that's connected to the power system can result in power lines being energized to line voltage of 7,200 volts or higher, whether they're on the ground or still in the air. If your generator is not isolated from the Cullman EC distribution system, the transformer at your location acts in reverse and can actually step-up the normal household voltage of your generator to our system voltage. If your generator has energized power lines that are on the ground, the energized lines could prove to be a safety hazard to you, your family, and especially the linemen working to restore power. As a matter of fact, a utility worker who was repairing damage from Hurricane Dennis was killed this past July in south Alabama because of an improperly installed generator. It is up to you to ensure the safety Alabama, July 14, 2005 - Sumter Electric Cooperative (SECO) officials report that a South Carolina lineman helping to restore power in Alabama after the damage caused by Hurricane Dennis was killed late Tuesday, reportedly by an improperly installed customer generator.Alabama authorities are looking for the person responsible and indicate that charges are pending all electric connections must comply with the National Electrical Code. You may be liable for damage to property or injury to people that may result from an improperly installed or operation of an emergency generator. When some minds are made up, no amount of evidence or reasoning can convince them their arguments are faulty. I doubt if they will even respond to your excellent post. |
#87
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Pete C." wrote in message ... JoeSixPack wrote: Incredibly stupid discussion. A service transformer steps voltage down from say, 7,200 volts to 240/120 volts. Backfeed 240 volts through the transformer, and 7,200 volts goes back out through the line. Anyone toucing the line can be killed at those voltages with very little current (milliamps in fact). It can and does happen, so stop using your limited knowledge to reach dangerous conclusions. Um, it only take milliamps to kill you at 120/240 volts as well. The only difference between 120/240 and 7,200 is amount of insulation required to protect you. Pete C. Exactly right. It only takes milliamps to kill you, but the greater the voltage, the more milliamps are driven through your skin and into your body. More milliamps does not equal more dead. Dead is dead and once you're past the threshold the voltage is irrelevant. Pete C. |
#88
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Spud" wrote in message ... "Steve Kraus" wrote in message nk.net... Me wrote: Your thinking is just plain wrong..... No, I think I'm on solid ground when I say that a load measuring in many megaWatts, maybe hundreds of megaWatts depending on the area of the power outage that I am downstream of, is essentially the same as shorting the generator output to ground. What about the downed power line your neighbors, and you. http://www.google.com/ In the aftermath of a disaster there are circumstances that circumvent conventional safety procedures. The utility companies rely heavily on independent construction firms to quickly restore utility lines. Private contractor employees are sometimes less familiars with the territory and the established utility company procedures. On top of everything else there is the stress caused by working long hours in inclement conditions and the pressure to restore power to thousands of customers some of whom are in dire need. A line crew was dispatched at night to restore power to a small restaurant in a mountainous area. The restaurant was served by a 3-phase, 12.47-kV, tapline, three spans in length. "The crew found that tree limbs had fallen into a corner pole (one span from the restaurant) short-circuiting the line and blowing the fuses back at the tap pole. They also discovered that the restaurant was using a generator to maintain service." The foreman confirmed that the main breaker at the restaurant was open, isolating the utility service. The crew tested and grounded the line a the tap pole and began repairs. When one lineman climbed the corner pole to remove limbs, he discovered that the jumpers and connectors were damaged and decided to replace them. "When he removed the jumpers, he was positioned in such a way that he was in contact with the under grounded portion of the line," continues Drew. For some reason, the restaurant owner was checking the generator and inadvertently closed the main breaker, backing power through the transformer bank and energizing the line up to the open jumpers. The lineman received a severe shock and died. 8/29/2005 As the number of personal electric generators grows, so does the threat of injury to utility workers and generator operators. If you connect a generator to your electrical panel without isolating it, it 's simply a disaster waiting to happen. A generator that's connected to the power system can result in power lines being energized to line voltage of 7,200 volts or higher, whether they're on the ground or still in the air. If your generator is not isolated from the Cullman EC distribution system, the transformer at your location acts in reverse and can actually step-up the normal household voltage of your generator to our system voltage. If your generator has energized power lines that are on the ground, the energized lines could prove to be a safety hazard to you, your family, and especially the linemen working to restore power. As a matter of fact, a utility worker who was repairing damage from Hurricane Dennis was killed this past July in south Alabama because of an improperly installed generator. It is up to you to ensure the safety Alabama, July 14, 2005 - Sumter Electric Cooperative (SECO) officials report that a South Carolina lineman helping to restore power in Alabama after the damage caused by Hurricane Dennis was killed late Tuesday, reportedly by an improperly installed customer generator.Alabama authorities are looking for the person responsible and indicate that charges are pending all electric connections must comply with the National Electrical Code. You may be liable for damage to property or injury to people that may result from an improperly installed or operation of an emergency generator. When some minds are made up, no amount of evidence or reasoning can convince them their arguments are faulty. I doubt if they will even respond to your excellent post. The first story in his "excellent" post once again shows that the ultimate cause of the lineman's death was his own carelessness in not following proper procedures, not the generator. He was clearly not wearing his HV gloves or other protective gear. The second story contains no details so a determination of the ultimate cause can't be made. I searched around and was unable to find a detailed report on this incident. It is quite likely that the ultimate cause of the death will be the lineman's own carelessness. The established procedures for line work, if followed will keep the lineman safe regardless of the electrical state of the lines. I'd be quite interested if you have a detailed report of a fatality where all procedures were followed. Pete C. |
#89
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Backfeed generator through dryer outlet?
JoeSixPack writes:
Your limited knowledge and limited reasoning power ... You know nothing of who I am, and are quite mistaken. |
#90
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Backfeed generator through dryer outlet?
Pop wrote:
Wow, there's so much bull here it's almost amazing. "Pete C." wrote in message ... ... : : There is nothing improper or unsafe about a temporary generator hookup : when done **by a competent person**. " === If that's the basis of your comments, it's silly - these posts aren't about a vague descrition of a "competent" person. Throwing the main breaker" is exactly : what some approved transfer switches do, === No, it is not. They connect to or disconnect power from/to a predetermined path. The main breaker is not "thrown" by the transfer switch. they have two very ordinary : circuit breakers mounted opposite each other and a link bar between the : handles. The only difference between this arrangement and the "turn off : the main and back feed the dryer circuit" temporary connection is the : link bar. === Guess you're making apoint here, but not sure what it is. : : A competent person === Meaningless term again. Vague, not useful or meaningful. You mean a licensed electrician or more from the sound of it. switches off and tags the main breaker before they : even haul out the generator, double checks it again after turning off : the dryer circuit breaker and connecting the "suicide cable", starts the : generator and then finally reviews the main breaker once more before : turning on the dryer circuit breaker to power the panel. === Oh, but they don't notify/chase out the neighborhood kids, pets and others? : : : The fact that the NEC requires generators to be connected : with isolation switches seems to go right over their heads. === No, I haven't seen much evidence of that. Pooly stated comment and not what I think you meant to say. : They apparently think it's ok for them to bypass code : requirements because 'they know what they're doing' and === But, if they "know what they're doing", wouldn't that make them a "competent person"? : neither them, nor someone else trying to use their generator : will ever make a mistake! Pretty arrogant attitude if you : ask me. === Yabut, it sounds just like your attitude earlier in this post. : : The NEC requires double throw transfer switches or approved equivalents : for permanent generator installations. A temporary hookup of a portable : generator in an emergency situation is not within the scope of the NEC. : Nothing "arrogant" about not not following code that is not applicable. === True, but ... there are a couple sections of the NEC you're apparently not familiar with, plus you totally ignore any local codes in that statement. : : : Bottom line - if you're going to use a generator to energize : your home do it right! Use an isolation switch! The code : requires it for the safety of everyone involved! === No, use a Transfer Switch. An "isolation" switch in this context is meaningless. : : It is asinine to claim that you should always install a transfer switch : in order to connect a generator, === No, it is assinine to make the ego-centric statements you've made, though. Something tells me you only -think- you are a "competent person". Else you wouldn't try to make most of these statements. transfer switches only make sense in : permanent installations. === No, they make a tremendous amount of sense. They make it easy, quick to do, and about as close to foolproof as you can make the situation. If Mom's the only one home and the pipes are freezing, all she has to do is start the generator by pusing the button, then turn on the power with the transfer switch. We'd be up and running before your "competent" guy even found his cordsets. Our situation isn't quite as neat: Here, you first have to roll the generator out of the garage and over to the porch, about 5 feet from the garage door, and plug it into the house first. Quite a hardship, but ... it's reliable and works. Ice Storm Survivor Pop : : Pete C. The only bull here is yours in trying to hack things out of context. Try again and this time leave everything in place and in context. Pete C. |
#91
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. I'm well aware of how a transformer works, in fact I was the only one to pass my power distribution course with a perfect score (all weekly tests, mid term and final 100% correct). My comments are 100% factually accurate. Please provide specific examples with references to what you think I am incorrect on. The bottom line is that you can not kill a lineman by inadvertently back feeding the mains. In order for the lineman to be killed he must also not follow established procedures for his work. Pete C. |
#92
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Backfeed generator through dryer outlet?
Chris Lewis wrote:
According to Pete C. : I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. I'm sure that a linesman whose been putting in 16 hour days for a week reconnecting lines after a hurricane will appreciate the attitude about booby traps. Not a booby trap, a normal job hazard and one that the standard procedures for the job address. Secondly, who said it's only linesmen? Last I heard, homeowners don't have such training, and a 4KV+ line lying in the ground isn't biased as to who it bites. Including unwary homeowners. Indeed, a live downed line can fry anyone that comes in contact with it, regardless of the source it is energized from. "Always assume any downed power line is live". Pete C. -- Chris Lewis, Una confibula non set est It's not just anyone who gets a Starship Cruiser class named after them. |
#93
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Backfeed generator through dryer outlet?
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#94
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Backfeed generator through dryer outlet?
Pete C. wrote: Waldo wrote: Vaughn wrote: "Pop" wrote in message ... Sooo, all that "data" means it's OK to kill someone that way as long as it's just a once in awhile thing, eh? "Snot my fault; he shouldn'ta been workin so tired trying to help all dem peoples!" Oh dear! Whenever this subject comes up, we never fail to get the same fodder from the amateur Internet moralists. Nothing is fail safe, I point my car at hundreds of innocent people every day and there is nothing to keep me from accidentally killing them, save my (very average) driving skills. Please save the moralizing and stick to the facts. Vaughn Well, it amazes me that there are so many people that have so many excuses for not properly, and safely, connecting their generators to their electrical systems. They talk about safely using suicide cords, throwing main breakers and other hogwash such as using a sign to remind them to throw the breakers. There is nothing improper or unsafe about a temporary generator hookup when done by a competent person. "Throwing the main breaker" is exactly what some approved transfer switches do, they have two very ordinary circuit breakers mounted opposite each other and a link bar between the handles. The only difference between this arrangement and the "turn off the main and back feed the dryer circuit" temporary connection is the link bar. Not quite. A transfer switch prevents the possibility of having both sides connected at the same time. A competent person switches off and tags the main breaker before they even haul out the generator, double checks it again after turning off the dryer circuit breaker and connecting the "suicide cable", starts the generator and then finally reviews the main breaker once more before turning on the dryer circuit breaker to power the panel. Depends upon your definition of a competent person. Joe-blow may certainly think he's competent because he knows how to do it as you described above. I think I'm competent and that's why my generator hookup is to code requirements - via a transfer switch and proper sized cable and connectors. The fact that the NEC requires generators to be connected with isolation switches My bad, should have read 'transfer switches' seems to go right over their heads. They apparently think it's ok for them to bypass code requirements because 'they know what they're doing' and neither them, nor someone else trying to use their generator will ever make a mistake! Pretty arrogant attitude if you ask me. The NEC requires double throw transfer switches or approved equivalents for permanent generator installations. A temporary hookup of a portable generator in an emergency situation is not within the scope of the NEC. Nothing "arrogant" about not not following code that is not applicable. Agreed, but depends upon your definition of an emergency situation. If someone is on a heart-lung machine, or something of that nature, and a back-up power source is not available and a generator must be brought in to provide power then I would consider that to be an emergency requirement. But a power outage for a few hours is not a real emergency for most homes, an inconvenience perhaps, but not an emergency. Bottom line - if you're going to use a generator to energize your home do it right! Use an isolation switch! The code requires it for the safety of everyone involved! It is asinine to claim that you should always install a transfer switch in order to connect a generator, transfer switches only make sense in permanent installations. And how do you define a permanent installation? I have a portable generator that gets connected through a transfer switch to the house during extended power outages. When line power comes back on the generator gets disconnected and rolled back into the shop. This is not a permanent installation, but code still requires it be connected via a transfer switch. If a person has a generator on hand and intends to use it during power outages then that person should have the means to connect it properly and safely.. Waldo Pete C. |
#96
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Backfeed generator through dryer outlet?
"Pete C." wrote: JoeSixPack wrote: "Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. I'm well aware of how a transformer works, in fact I was the only one to pass my power distribution course with a perfect score (all weekly tests, mid term and final 100% correct). My comments are 100% factually accurate. Please provide specific examples with references to what you think I am incorrect on. The bottom line is that you can not kill a lineman by inadvertently back feeding the mains. In order for the lineman to be killed he must also not follow established procedures for his work. Pete C. You are also failing to follow the long standard engineering practice of having a system setup such that it requires a minimum of two failures for a life threatening fault. You are advocating that homeowners with generators intentionally provide the first failure. So now that lineman is only one ripped glove away from being electrocuted. You may be book smart, but you sure are stupid. --Dale |
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Backfeed generator through dryer outlet?
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Backfeed generator through dryer outlet?
Waldo wrote:
Pete C. wrote: Waldo wrote: Vaughn wrote: "Pop" wrote in message ... Sooo, all that "data" means it's OK to kill someone that way as long as it's just a once in awhile thing, eh? "Snot my fault; he shouldn'ta been workin so tired trying to help all dem peoples!" Oh dear! Whenever this subject comes up, we never fail to get the same fodder from the amateur Internet moralists. Nothing is fail safe, I point my car at hundreds of innocent people every day and there is nothing to keep me from accidentally killing them, save my (very average) driving skills. Please save the moralizing and stick to the facts. Vaughn Well, it amazes me that there are so many people that have so many excuses for not properly, and safely, connecting their generators to their electrical systems. They talk about safely using suicide cords, throwing main breakers and other hogwash such as using a sign to remind them to throw the breakers. There is nothing improper or unsafe about a temporary generator hookup when done by a competent person. "Throwing the main breaker" is exactly what some approved transfer switches do, they have two very ordinary circuit breakers mounted opposite each other and a link bar between the handles. The only difference between this arrangement and the "turn off the main and back feed the dryer circuit" temporary connection is the link bar. Not quite. A transfer switch prevents the possibility of having both sides connected at the same time. A competent person switches off and tags the main breaker before they even haul out the generator, double checks it again after turning off the dryer circuit breaker and connecting the "suicide cable", starts the generator and then finally reviews the main breaker once more before turning on the dryer circuit breaker to power the panel. Depends upon your definition of a competent person. Joe-blow may certainly think he's competent because he knows how to do it as you described above. I think I'm competent and that's why my generator hookup is to code requirements - via a transfer switch and proper sized cable and connectors. The fact that the NEC requires generators to be connected with isolation switches My bad, should have read 'transfer switches' seems to go right over their heads. They apparently think it's ok for them to bypass code requirements because 'they know what they're doing' and neither them, nor someone else trying to use their generator will ever make a mistake! Pretty arrogant attitude if you ask me. The NEC requires double throw transfer switches or approved equivalents for permanent generator installations. A temporary hookup of a portable generator in an emergency situation is not within the scope of the NEC. Nothing "arrogant" about not not following code that is not applicable. Agreed, but depends upon your definition of an emergency situation. If someone is on a heart-lung machine, or something of that nature, and a back-up power source is not available and a generator must be brought in to provide power then I would consider that to be an emergency requirement. But a power outage for a few hours is not a real emergency for most homes, an inconvenience perhaps, but not an emergency. Bottom line - if you're going to use a generator to energize your home do it right! Use an isolation switch! The code requires it for the safety of everyone involved! It is asinine to claim that you should always install a transfer switch in order to connect a generator, transfer switches only make sense in permanent installations. And how do you define a permanent installation? I have a portable generator that gets connected through a transfer switch to the house during extended power outages. When line power comes back on the generator gets disconnected and rolled back into the shop. This is not a permanent installation, but code still requires it be connected via a transfer switch. If a person has a generator on hand and intends to use it during power outages then that person should have the means to connect it properly and safely.. Waldo Or don't connect it at all... You can do pretty well with a generator and a couple of long extension cords. Bob |
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Backfeed generator through dryer outlet?
In article ,
"Pete C." wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. Then you haven't lived long enough, or inspected enough installations..... Having a Transfer Switch that doesn't switch the Neutral is applicable in the NEC, and legal in some situations. However, and this is a BIG However, if the System Ground should become faulty or the Netural resistance to ground start to rise due to corrosion or other problems, then out of Ballance Backfeeding on a 120/240Vac Single Phase system can happen. Nothing mechanical stays the same forever, and forever is a very long time. **** Happens, and folks that don't understand that are doomed to live the results, for when the wrong "**** Happens" in their world....... Some folks choose to only switch the Hot Legs, but the better way to do it is to switch both Hot and Neutral, and only keep the Ground continious..... Me |
#100
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Backfeed generator through dryer outlet?
Waldo wrote:
Pete C. wrote: Waldo wrote: Vaughn wrote: "Pop" wrote in message ... Sooo, all that "data" means it's OK to kill someone that way as long as it's just a once in awhile thing, eh? "Snot my fault; he shouldn'ta been workin so tired trying to help all dem peoples!" Oh dear! Whenever this subject comes up, we never fail to get the same fodder from the amateur Internet moralists. Nothing is fail safe, I point my car at hundreds of innocent people every day and there is nothing to keep me from accidentally killing them, save my (very average) driving skills. Please save the moralizing and stick to the facts. Vaughn Well, it amazes me that there are so many people that have so many excuses for not properly, and safely, connecting their generators to their electrical systems. They talk about safely using suicide cords, throwing main breakers and other hogwash such as using a sign to remind them to throw the breakers. There is nothing improper or unsafe about a temporary generator hookup when done by a competent person. "Throwing the main breaker" is exactly what some approved transfer switches do, they have two very ordinary circuit breakers mounted opposite each other and a link bar between the handles. The only difference between this arrangement and the "turn off the main and back feed the dryer circuit" temporary connection is the link bar. Not quite. A transfer switch prevents the possibility of having both sides connected at the same time. Well, that is what they attempt to do. They do however fail on occasion. A competent person switches off and tags the main breaker before they even haul out the generator, double checks it again after turning off the dryer circuit breaker and connecting the "suicide cable", starts the generator and then finally reviews the main breaker once more before turning on the dryer circuit breaker to power the panel. Depends upon your definition of a competent person. Joe-blow may certainly think he's competent because he knows how to do it as you described above. I think I'm competent and that's why my generator hookup is to code requirements - via a transfer switch and proper sized cable and connectors. Your generator hookup is a permanent installation, even if the generator itself is not part of the installation. Pretty common to see at telecom sites as well, permanently installed transfer switchgear and a big ol' IEC style plug on the outside of the building (or ped) to connect a towable generator to when needed. Allows a smaller fleet of towable generators to service multiple sites and also allows central storage and servicing of those generators. Also quite common to see a small Honda generator chained to the base of a pole and powering a cable TV power supply. No transfer switch here, just switch of the main disconnect and wire in the extension cord. The fact that the NEC requires generators to be connected with isolation switches My bad, should have read 'transfer switches' An isolating transfer switch would be one type. Also have less common make before break paralleling transfer switches. seems to go right over their heads. They apparently think it's ok for them to bypass code requirements because 'they know what they're doing' and neither them, nor someone else trying to use their generator will ever make a mistake! Pretty arrogant attitude if you ask me. The NEC requires double throw transfer switches or approved equivalents for permanent generator installations. A temporary hookup of a portable generator in an emergency situation is not within the scope of the NEC. Nothing "arrogant" about not not following code that is not applicable. Agreed, but depends upon your definition of an emergency situation. If someone is on a heart-lung machine, or something of that nature, and a back-up power source is not available and a generator must be brought in to provide power then I would consider that to be an emergency requirement. But a power outage for a few hours is not a real emergency for most homes, an inconvenience perhaps, but not an emergency. Everything is relative, but in an ice storm where there is a real risk of damage from frozen pipes in a short time period that would meet my definition of emergency. If there are children or elderly who are not as able to handle the cold as a typical healthy adult that would be an emergency. In hot weather were some people would be at risk without A/C. Bottom line - if you're going to use a generator to energize your home do it right! Use an isolation switch! The code requires it for the safety of everyone involved! It is asinine to claim that you should always install a transfer switch in order to connect a generator, transfer switches only make sense in permanent installations. And how do you define a permanent installation? I have a portable generator that gets connected through a transfer switch to the house during extended power outages. When line power comes back on the generator gets disconnected and rolled back into the shop. This is not a permanent installation, but code still requires it be connected via a transfer switch. You have a permanent installation of generator connection facilities. The generator itself need not be a part of that installation. If a person has a generator on hand and intends to use it during power outages then that person should have the means to connect it properly and safely.. And that means can include the knowledge of how to make a safe temporary connection for the one or two times a year they may need it. If it's a fairly frequent occurrence then it justifies at least a basic transfer switch installation, once or twice a year does not if the user is competent. Pete C. |
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Backfeed generator through dryer outlet?
Dale Farmer wrote:
"Pete C." wrote: JoeSixPack wrote: "Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. I'm well aware of how a transformer works, in fact I was the only one to pass my power distribution course with a perfect score (all weekly tests, mid term and final 100% correct). My comments are 100% factually accurate. Please provide specific examples with references to what you think I am incorrect on. The bottom line is that you can not kill a lineman by inadvertently back feeding the mains. In order for the lineman to be killed he must also not follow established procedures for his work. Pete C. You are also failing to follow the long standard engineering practice of having a system setup such that it requires a minimum of two failures for a life threatening fault. You are advocating that homeowners with generators intentionally provide the first failure. So now that lineman is only one ripped glove away from being electrocuted. You may be book smart, but you sure are stupid. --Dale The entire public power utility distribution grid is not built to a "two failures for a life threatening fault" standard. Pete C. |
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Backfeed generator through dryer outlet?
"Pete C." wrote in message ... JoeSixPack wrote: "Spud" wrote in message ... "Steve Kraus" wrote in message nk.net... Me wrote: Your thinking is just plain wrong..... No, I think I'm on solid ground when I say that a load measuring in many megaWatts, maybe hundreds of megaWatts depending on the area of the power outage that I am downstream of, is essentially the same as shorting the generator output to ground. What about the downed power line your neighbors, and you. http://www.google.com/ In the aftermath of a disaster there are circumstances that circumvent conventional safety procedures. The utility companies rely heavily on independent construction firms to quickly restore utility lines. Private contractor employees are sometimes less familiars with the territory and the established utility company procedures. On top of everything else there is the stress caused by working long hours in inclement conditions and the pressure to restore power to thousands of customers some of whom are in dire need. A line crew was dispatched at night to restore power to a small restaurant in a mountainous area. The restaurant was served by a 3-phase, 12.47-kV, tapline, three spans in length. "The crew found that tree limbs had fallen into a corner pole (one span from the restaurant) short-circuiting the line and blowing the fuses back at the tap pole. They also discovered that the restaurant was using a generator to maintain service." The foreman confirmed that the main breaker at the restaurant was open, isolating the utility service. The crew tested and grounded the line a the tap pole and began repairs. When one lineman climbed the corner pole to remove limbs, he discovered that the jumpers and connectors were damaged and decided to replace them. "When he removed the jumpers, he was positioned in such a way that he was in contact with the under grounded portion of the line," continues Drew. For some reason, the restaurant owner was checking the generator and inadvertently closed the main breaker, backing power through the transformer bank and energizing the line up to the open jumpers. The lineman received a severe shock and died. 8/29/2005 As the number of personal electric generators grows, so does the threat of injury to utility workers and generator operators. If you connect a generator to your electrical panel without isolating it, it 's simply a disaster waiting to happen. A generator that's connected to the power system can result in power lines being energized to line voltage of 7,200 volts or higher, whether they're on the ground or still in the air. If your generator is not isolated from the Cullman EC distribution system, the transformer at your location acts in reverse and can actually step-up the normal household voltage of your generator to our system voltage. If your generator has energized power lines that are on the ground, the energized lines could prove to be a safety hazard to you, your family, and especially the linemen working to restore power. As a matter of fact, a utility worker who was repairing damage from Hurricane Dennis was killed this past July in south Alabama because of an improperly installed generator. It is up to you to ensure the safety Alabama, July 14, 2005 - Sumter Electric Cooperative (SECO) officials report that a South Carolina lineman helping to restore power in Alabama after the damage caused by Hurricane Dennis was killed late Tuesday, reportedly by an improperly installed customer generator.Alabama authorities are looking for the person responsible and indicate that charges are pending all electric connections must comply with the National Electrical Code. You may be liable for damage to property or injury to people that may result from an improperly installed or operation of an emergency generator. When some minds are made up, no amount of evidence or reasoning can convince them their arguments are faulty. I doubt if they will even respond to your excellent post. The first story in his "excellent" post once again shows that the ultimate cause of the lineman's death was his own carelessness in not following proper procedures, not the generator. He was clearly not wearing his HV gloves or other protective gear. The second story contains no details so a determination of the ultimate cause can't be made. I searched around and was unable to find a detailed report on this incident. It is quite likely that the ultimate cause of the death will be the lineman's own carelessness. The established procedures for line work, if followed will keep the lineman safe regardless of the electrical state of the lines. I'd be quite interested if you have a detailed report of a fatality where all procedures were followed. Pete C. So it's OK to backfeed? Thanks. |
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Backfeed generator through dryer outlet?
"Pete C." wrote in message ... Dale Farmer wrote: "Pete C." wrote: JoeSixPack wrote: "Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. I'm well aware of how a transformer works, in fact I was the only one to pass my power distribution course with a perfect score (all weekly tests, mid term and final 100% correct). My comments are 100% factually accurate. Please provide specific examples with references to what you think I am incorrect on. The bottom line is that you can not kill a lineman by inadvertently back feeding the mains. In order for the lineman to be killed he must also not follow established procedures for his work. Pete C. You are also failing to follow the long standard engineering practice of having a system setup such that it requires a minimum of two failures for a life threatening fault. You are advocating that homeowners with generators intentionally provide the first failure. So now that lineman is only one ripped glove away from being electrocuted. You may be book smart, but you sure are stupid. --Dale The entire public power utility distribution grid is not built to a "two failures for a life threatening fault" standard. Pete C. I rarely resort to this type of language, but what moron believes a second failsafe procedure is a waste of time, especially when the first one is relying on the human factor? |
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Backfeed generator through dryer outlet?
"Richard J Kinch" wrote in message . .. JoeSixPack writes: Your limited knowledge and limited reasoning power ... You know nothing of who I am, and are quite mistaken. |
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Backfeed generator through dryer outlet?
"Richard J Kinch" wrote in message . .. JoeSixPack writes: Your limited knowledge and limited reasoning power ... You know nothing of who I am, and are quite mistaken. True. I can only comment on the lack of reason and knowledge in your post. You may be a genius in other respects. |
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Backfeed generator through dryer outlet?
Me wrote:
In article , "Pete C." wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. Then you haven't lived long enough, or inspected enough installations..... Having a Transfer Switch that doesn't switch the Neutral is applicable in the NEC, and legal in some situations. However, and this is a BIG However, if the System Ground should become faulty or the Netural resistance to ground start to rise due to corrosion or other problems, then out of Ballance Backfeeding on a 120/240Vac Single Phase system can happen. Nothing mechanical stays the same forever, and forever is a very long time. **** Happens, and folks that don't understand that are doomed to live the results, for when the wrong "**** Happens" in their world....... Some folks choose to only switch the Hot Legs, but the better way to do it is to switch both Hot and Neutral, and only keep the Ground continious..... Me The last time I looked at "real" transfer switches from the major brands through about 600A, virtually all were solid neutral units. You could of course use a three pole (a.k.a. three phase) unit to switch the neutral in a 120/240V application, but you'd likely have to special order it to get the single phase monitor and control electronics. All of the little "Gen-Trans" and similar consumer level units I've seen are solid neutral as well. I'm pretty sure that it's unlikely you'll see a transfer switch that switches the neutral as well outside of a fairly large industrial / commercial application. Pete C. |
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Pete C." wrote in message ... JoeSixPack wrote: "Spud" wrote in message ... "Steve Kraus" wrote in message nk.net... Me wrote: Your thinking is just plain wrong..... No, I think I'm on solid ground when I say that a load measuring in many megaWatts, maybe hundreds of megaWatts depending on the area of the power outage that I am downstream of, is essentially the same as shorting the generator output to ground. What about the downed power line your neighbors, and you. http://www.google.com/ In the aftermath of a disaster there are circumstances that circumvent conventional safety procedures. The utility companies rely heavily on independent construction firms to quickly restore utility lines. Private contractor employees are sometimes less familiars with the territory and the established utility company procedures. On top of everything else there is the stress caused by working long hours in inclement conditions and the pressure to restore power to thousands of customers some of whom are in dire need. A line crew was dispatched at night to restore power to a small restaurant in a mountainous area. The restaurant was served by a 3-phase, 12.47-kV, tapline, three spans in length. "The crew found that tree limbs had fallen into a corner pole (one span from the restaurant) short-circuiting the line and blowing the fuses back at the tap pole. They also discovered that the restaurant was using a generator to maintain service." The foreman confirmed that the main breaker at the restaurant was open, isolating the utility service. The crew tested and grounded the line a the tap pole and began repairs. When one lineman climbed the corner pole to remove limbs, he discovered that the jumpers and connectors were damaged and decided to replace them. "When he removed the jumpers, he was positioned in such a way that he was in contact with the under grounded portion of the line," continues Drew. For some reason, the restaurant owner was checking the generator and inadvertently closed the main breaker, backing power through the transformer bank and energizing the line up to the open jumpers. The lineman received a severe shock and died. 8/29/2005 As the number of personal electric generators grows, so does the threat of injury to utility workers and generator operators. If you connect a generator to your electrical panel without isolating it, it 's simply a disaster waiting to happen. A generator that's connected to the power system can result in power lines being energized to line voltage of 7,200 volts or higher, whether they're on the ground or still in the air. If your generator is not isolated from the Cullman EC distribution system, the transformer at your location acts in reverse and can actually step-up the normal household voltage of your generator to our system voltage. If your generator has energized power lines that are on the ground, the energized lines could prove to be a safety hazard to you, your family, and especially the linemen working to restore power. As a matter of fact, a utility worker who was repairing damage from Hurricane Dennis was killed this past July in south Alabama because of an improperly installed generator. It is up to you to ensure the safety Alabama, July 14, 2005 - Sumter Electric Cooperative (SECO) officials report that a South Carolina lineman helping to restore power in Alabama after the damage caused by Hurricane Dennis was killed late Tuesday, reportedly by an improperly installed customer generator.Alabama authorities are looking for the person responsible and indicate that charges are pending all electric connections must comply with the National Electrical Code. You may be liable for damage to property or injury to people that may result from an improperly installed or operation of an emergency generator. When some minds are made up, no amount of evidence or reasoning can convince them their arguments are faulty. I doubt if they will even respond to your excellent post. The first story in his "excellent" post once again shows that the ultimate cause of the lineman's death was his own carelessness in not following proper procedures, not the generator. He was clearly not wearing his HV gloves or other protective gear. The second story contains no details so a determination of the ultimate cause can't be made. I searched around and was unable to find a detailed report on this incident. It is quite likely that the ultimate cause of the death will be the lineman's own carelessness. The established procedures for line work, if followed will keep the lineman safe regardless of the electrical state of the lines. I'd be quite interested if you have a detailed report of a fatality where all procedures were followed. Pete C. So it's OK to backfeed? Thanks. No, but you won't kill a utility lineman as many have asserted. Pete C. |
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Backfeed generator through dryer outlet?
Pete C. wrote:
I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. My transfer switch switches both hots and neutral. http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html |
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Backfeed generator through dryer outlet?
JoeSixPack writes:
You know nothing of who I am, and are quite mistaken. True. I can only comment on ... Trolling anonymous coward. |
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Backfeed generator through dryer outlet?
JoeSixPack wrote:
"Pete C." wrote in message ... Dale Farmer wrote: "Pete C." wrote: JoeSixPack wrote: "Pete C." wrote in message ... JoeSixPack wrote: "Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Stop spreading dangerous misinformation. Backfeeding generators can and do kill linemen. http://www.clatskaniepud.com/Generators.htm http://www.statefarm.com/consumer/vh...es/generat.htm http://www.cpsc.gov/cpscpub/pubs/portgen.html http://eweb.org/home/energy/generator/index.htm A few of the many, many links that warn of this hazard. You are a hazard. There is absolutely no misinformation in what I posted. The links you list border on misinformation in their omissions. I indicated that if you screw up and back feed the mains you will provide an opportunity for a careless lineman to kill themselves, not kill them directly. This is a *fact*. A lineman following established procedures will *not* be killed by a back feeding generator. As I've noted, every case I've seen where a lineman was "killed by an improperly connected generator" has clearly shown that the lineman in question did not follow proper procedures. If you have references to a case where a lineman followed procedures and was killed by an "improperly connected generator" I'd like to see it. I bet you also believe you can't put metal in a microwave oven... Pete C. What color is the sun in your little world there? Do you not know that when you put 240V back through the transformer, it energizes the lines to 7200 Volts? Do you know how little current it takes to kill someone at such a voltage? Your comments are stupid and irresponsible. You just have to admit you're wrong sometimes, and there's no amount of explaining that can save you. I'm well aware of how a transformer works, in fact I was the only one to pass my power distribution course with a perfect score (all weekly tests, mid term and final 100% correct). My comments are 100% factually accurate. Please provide specific examples with references to what you think I am incorrect on. The bottom line is that you can not kill a lineman by inadvertently back feeding the mains. In order for the lineman to be killed he must also not follow established procedures for his work. Pete C. You are also failing to follow the long standard engineering practice of having a system setup such that it requires a minimum of two failures for a life threatening fault. You are advocating that homeowners with generators intentionally provide the first failure. So now that lineman is only one ripped glove away from being electrocuted. You may be book smart, but you sure are stupid. --Dale The entire public power utility distribution grid is not built to a "two failures for a life threatening fault" standard. Pete C. I rarely resort to this type of language, but what moron believes a second failsafe procedure is a waste of time, especially when the first one is relying on the human factor? The second failsafe procedure is the utility workers training which tells them to treat everything as live, always use their protective gear, ground lines they are working on as applicable, etc. If you want "two failures for a life threatening fault", then redesign the entire electrical distribution infrastructure so that every transformer is isolating and every line segment is floating, no grounds anywhere. That way any single fault will not in itself cause a life threatening fault. One fault would only reference the voltage on that segment to ground or whatever and not cause a dangerous situation without a second fault to provide another contact point at a different relative voltage. Pete C. |
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Backfeed generator through dryer outlet?
"Me" wrote in message ... In article , "Pete C." wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. Then you haven't lived long enough, or inspected enough installations..... Having a Transfer Switch that doesn't switch the Neutral is applicable in the NEC, and legal in some situations. However, and this is a BIG However, if the System Ground should become faulty or the Netural resistance to ground start to rise due to corrosion or other problems, then out of Ballance Backfeeding on a 120/240Vac Single Phase system can happen. Nothing mechanical stays the same forever, and forever is a very long time. **** Happens, and folks that don't understand that are doomed to live the results, for when the wrong "**** Happens" in their world....... Some folks choose to only switch the Hot Legs, but the better way to do it is to switch both Hot and Neutral, and only keep the Ground continious..... Me Your point sounds valid, and I certainly believe "ship happens" (given enough time **** will always happen), but can you cite a specific make and model transfer switch for a residential application that switches the neutral? John |
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Backfeed generator through dryer outlet?
Steve Spence wrote:
Pete C. wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. My transfer switch switches both hots and neutral. http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html The picture is a bit small, but it sure looks like a pair of 2 pole contactors. I can't tell if they have auxiliary contacts installed for electrical interlock. It looks rather like the auto transfer switches I've seen on RVs. If they are indeed 2 pole contactors then you're either running 120V only or have a solid neutral. I built a small transfer switch myself with a pair of contactors with auxiliary contacts installed to allow for electrical interlock of the contactors coils. When a contactor is energized the NC aux contacts open the circuit to the coil of the other contactor preventing it from being energized. Three possible states, one contactor on, the other contactor on or both contactors off. Pete C. |
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Backfeed generator through dryer outlet?
"Pete C." wrote:
Steve Spence wrote: Pete C. wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. My transfer switch switches both hots and neutral. http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html The picture is a bit small, but it sure looks like a pair of 2 pole contactors. I can't tell if they have auxiliary contacts installed for electrical interlock. It looks rather like the auto transfer switches I've seen on RVs. If they are indeed 2 pole contactors then you're either running 120V only or have a solid neutral. I built a small transfer switch myself with a pair of contactors with auxiliary contacts installed to allow for electrical interlock of the contactors coils. When a contactor is energized the NC aux contacts open the circuit to the coil of the other contactor preventing it from being energized. Three possible states, one contactor on, the other contactor on or both contactors off. Pete C. Come to think of it, if it is the RV type it could indeed switch the neutral by using the contactors together and utilizing the NC and NO sets of contacts with no provision for an "off" state. NC to connect to one source until the other source is available, cycles the time delay relay and then energizes both contactors. Of course this type of setup has the potential for a nasty failure mode if one contactor fails. Pete C. |
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Backfeed generator through dryer outlet?
JOHN D wrote:
"Me" wrote in message ... In article , "Pete C." wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. Then you haven't lived long enough, or inspected enough installations..... Having a Transfer Switch that doesn't switch the Neutral is applicable in the NEC, and legal in some situations. However, and this is a BIG However, if the System Ground should become faulty or the Netural resistance to ground start to rise due to corrosion or other problems, then out of Ballance Backfeeding on a 120/240Vac Single Phase system can happen. Nothing mechanical stays the same forever, and forever is a very long time. **** Happens, and folks that don't understand that are doomed to live the results, for when the wrong "**** Happens" in their world....... Some folks choose to only switch the Hot Legs, but the better way to do it is to switch both Hot and Neutral, and only keep the Ground continious..... Me Your point sounds valid, and I certainly believe "ship happens" (given enough time **** will always happen), but can you cite a specific make and model transfer switch for a residential application that switches the neutral? John yes, http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html |
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Backfeed generator through dryer outlet?
Pete C. wrote:
Steve Spence wrote: Pete C. wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. My transfer switch switches both hots and neutral. http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html The picture is a bit small, but it sure looks like a pair of 2 pole contactors. I can't tell if they have auxiliary contacts installed for electrical interlock. It looks rather like the auto transfer switches I've seen on RVs. If they are indeed 2 pole contactors then you're either running 120V only or have a solid neutral. I built a small transfer switch myself with a pair of contactors with auxiliary contacts installed to allow for electrical interlock of the contactors coils. When a contactor is energized the NC aux contacts open the circuit to the coil of the other contactor preventing it from being energized. Three possible states, one contactor on, the other contactor on or both contactors off. Pete C. The relay on the left switches the neutral, the relay on the right switches both hots. they are interlocked. -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html |
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Backfeed generator through dryer outlet?
"Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Regardless. If my installation allowed my wife/adult-son to energize a line from the home generator because I didn't bother installing a positive disconnect, and it killed an over-worked, tired lineman who missed one step in his safety procedures, the guy is still dead. Or some stranger touched a down line at an accident scene, that was supposedly switched off by the utility but wasn't actually de-energized yet because of my generator, they are still dead. And regardless of lawyers, wrongful death suits, contributing factors, or any other 'paper excuse', someone ending up dead because I skimped on a safety feature, isn't going to help me sleep at night. Some of us care more for our fellow man than to just say, "Well, they obviously didn't follow procedures", or "Another candidate for a Darwin award." Maybe you should go tell the widow of a dead lineman who was working for 20 hours trying to get people their power back, how it's obviously her spouse's fault that he's dead. Or the widow of the rescue squad guy that touched a live wire after the utility folks pulled all the fuses, trying to save someone else's life that they deserve the "Darwin Award" for the year. daestrom |
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Backfeed generator through dryer outlet?
"Pete C." wrote in message ... Waldo wrote: Vaughn wrote: "Pop" wrote in message ... Sooo, all that "data" means it's OK to kill someone that way as long as it's just a once in awhile thing, eh? "Snot my fault; he shouldn'ta been workin so tired trying to help all dem peoples!" Oh dear! Whenever this subject comes up, we never fail to get the same fodder from the amateur Internet moralists. Nothing is fail safe, I point my car at hundreds of innocent people every day and there is nothing to keep me from accidentally killing them, save my (very average) driving skills. Please save the moralizing and stick to the facts. Vaughn Well, it amazes me that there are so many people that have so many excuses for not properly, and safely, connecting their generators to their electrical systems. They talk about safely using suicide cords, throwing main breakers and other hogwash such as using a sign to remind them to throw the breakers. There is nothing improper or unsafe about a temporary generator hookup when done by a competent person. "Throwing the main breaker" is exactly what some approved transfer switches do, they have two very ordinary circuit breakers mounted opposite each other and a link bar between the handles. The only difference between this arrangement and the "turn off the main and back feed the dryer circuit" temporary connection is the link bar. And that inexpensive little link bar is too much trouble to install? A competent person switches off and tags the main breaker before they even haul out the generator, double checks it again after turning off the dryer circuit breaker and connecting the "suicide cable", starts the generator and then finally reviews the main breaker once more before turning on the dryer circuit breaker to power the panel. FYI, tags alone don't meet the OSHA requirements for tag-out/lock-out in residential setting. Tag-out only works if all employees/personel that have access to the area receive basic tag-out training. Otherwise, locks are required. But that's OSHA. I'm sure you'll argue that such rules don't apply in an emergency (except to the lineman that forgets a step in their procedure and ends up dead). BTW, is powering up your home to save $200 of beef in the freezer, or watch TV an 'emergency'?? daestrom |
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Backfeed generator through dryer outlet?
daestrom wrote:
"Pete C." wrote in message ... George wrote: Toller wrote: Bull. In the last 5 years we have had 3 poweroutages where I used my generator. There wasn't a lineman within 5 miles of me on any of them. My 2kw generator is going to power up 80 square miles? Don't think so. So you have some sort of radar/GPS/RFID system to determine the location of lineman? But lets say you don't and consider other scenerios. Suppose the primary is knocked down (ice storm etc) leaving you on a deenergized segment. So you thoughtfully engergize the secondary and hence the primary (7 Kv in my area) which may be laying on the ground or otherwise accessable. And my point being you can't possibly know about every condition and scenerio and that is why you install a disconnect so you don't have to. Remember the "Always assume a downed power line is live"? Also the main breaker on your service panel *is* a disconnect. The main thing here is the even if you, Joe Homeowner screw up and backfeed the mains, you have virtually zero chance of killing a lineman directly, only assisting a Darwin award candidate. Every report I've seen of a utility worker "killed by an improperly connected home generator" has shown that it was a perhaps overworked / over tired lineman who got careless and didn't follow procedures. Regardless. If my installation allowed my wife/adult-son to energize a line from the home generator I'm single, the switch gear is under control of a single competent person. because I didn't bother installing a positive disconnect The main breaker *is* a positive disconnect. It is not mechanically or electrically interlocked with the other breaker however. , and it killed an over-worked, tired lineman who missed one step in his safety procedures, the guy is still dead. Or some stranger touched a down line at an accident scene, that was supposedly switched off by the utility but wasn't actually de-energized yet because of my generator, they are still dead. Well, I'm not as concerned with avoiding enabling other people to injure themselves. Every time you drive your car you are also enabling other people to injure themselves and are relying on them to follow procedures such as crosswalks and traffic lights to prevent them from being injured by your car. And regardless of lawyers, wrongful death suits, contributing factors, or any other 'paper excuse', someone ending up dead because I skimped on a safety feature, isn't going to help me sleep at night. If you have sleep issues they have medication for that. Some of us care more for our fellow man than to just say, "Well, they obviously didn't follow procedures", or "Another candidate for a Darwin award." Maybe you should go tell the widow of a dead lineman who was working for 20 hours trying to get people their power back, how it's obviously her spouse's fault that he's dead. Or the widow of the rescue squad guy that touched a live wire after the utility folks pulled all the fuses, trying to save someone else's life that they deserve the "Darwin Award" for the year. daestrom Life is full of risks and as they say "They knew the job was dangerous when they took it". While I'd not be quite so blunt with that widow(er), the bottom line is that the person in question knew they were taking a risk by working excessive hours or short cutting procedures and the ultimate responsibility for the results of that risk land on their shoulders. I enable them to kill themselves every day by simply funding the power utility. Pete C. |
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Backfeed generator through dryer outlet?
Steve Spence wrote:
Pete C. wrote: Steve Spence wrote: Pete C. wrote: I've not seen any transfer switches that switch or isolate the neutral and I've seen many transfer switches. Pete C. My transfer switch switches both hots and neutral. http://www.green-trust.org/wiki/inde...ransfer_Switch -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html The picture is a bit small, but it sure looks like a pair of 2 pole contactors. I can't tell if they have auxiliary contacts installed for electrical interlock. It looks rather like the auto transfer switches I've seen on RVs. If they are indeed 2 pole contactors then you're either running 120V only or have a solid neutral. I built a small transfer switch myself with a pair of contactors with auxiliary contacts installed to allow for electrical interlock of the contactors coils. When a contactor is energized the NC aux contacts open the circuit to the coil of the other contactor preventing it from being energized. Three possible states, one contactor on, the other contactor on or both contactors off. Pete C. The relay on the left switches the neutral, the relay on the right switches both hots. they are interlocked. -- Steve Spence Dir., Green Trust, http://www.green-trust.org Contributing Editor, http://www.off-grid.net http://www.rebelwolf.com/essn.html What happens if a coil burns out on one of the contactors? One side switches and the other does not, you could end up with a situation where you have lost your neutral, i.e. hots from one source and neutral from the other source. Could be ugly. On the transfer switch I built I had a solid neutral, but only used the NO main contacts on the contactors. If a contactor coil were to fail I would not have a situation where I lost a neutral or a phase. The NC auxiliary contact blocks on the contactors were used to provide the interlock to prevent any possibility that both contactors could be energized at the same time. It would require two failures for that to occur, both the upstream control to try to energize both contactors and the failure of one of the aux contacts to allow it to actually happen. Pete C. |
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