|
| Comments and question. Just replaced the logic board on a Sears Craftsman (Chamberlain) operator. Apparent surge from lightning. Chamberlain offers a surge protector for the doors, their number CLSS1. I bought them for all my doors. In the package is an insert, looks like an afterthought. "CAUTION- do not install this device if there is not at least 10 meters (30 feet) or more of wire between the electrical outlet and the electrical service panel." No mention of this until one cuts open the blister package, made in China.
I know a bit about electricity, but the reason behind this escapes me. Lots of residential garages also have the electrical service panel with distances much less than 30 feet. In my case, the distance is about 25 feet. Anyone know what is the reason for the necessary distance? |
Follow-Up Postings:
|
- Posted by don_1_2006 (My Page) on Mon, Jun 25, 12 at 13:13
|
- Posted by bus_driver (My Page) on Mon, Jun 25, 12 at 13:58
| I did send a message as Don suggested. Reading the main package insert, there is a comment about plugging it into a GFCI and suggesting that it might not be best under some circumstances. The latest NEC requires that the ceiling receptacle for the GDO be GFCI protected. I disagree with that requirement, which applies only to installations made after that code provision became effective. GFCI for GDO and for receptacles 8' or more above the floor is absolutely unnecessary. But now required. |
|
- Posted by don_1_2006 (My Page) on Tue, Jun 26, 12 at 9:48
| I hope you will let us know what Chamberlain says about this. After an experience of 45 electric golf carts hooked up to GFCI's I have lost faith in those things. Thankfully it was temporary. |
|
- Posted by bus_driver (My Page) on Tue, Jun 26, 12 at 14:30
| No response yet. No doubt you know that a GFCI and a Surge protector are two different things with different purposes. For some commercial and industrial 3-phase installations, a different type of GFCI does offer protection for electrical equipment. But for 120 (and 240 volt) volt receptacles, the GFCI is intended for protection of people and typically offers no protection for equipment. The surge arrestor is intended to protect equipment and offers no direct protection for people. The CLSS1 is purported to protect the GDO, nothing more. |
|
- Posted by don_1_2006 (My Page) on Tue, Jun 26, 12 at 17:56
| Yes, thanks. |
|
| Reasons for that separation are obvious once basic electrical concepts are learned. This author has cited those reasons repeatedly in other discussions in this thread. Those reasons will be summarized here. A protector adjacent to an appliance can only block, stop, or absorb a surge. Since that is virtually impossible, then such protectors are best called scams. The effective protector must earth a surge before that surge can even be within the building. IOW the protector must connect a surge low impedance (ie 'less than 10 feet') to earth. Wire thickness is mostly irrelevant. Wire length and other negative factors such as sharp bends are critically important. If a protector is adjacent to the Sears, then it may earth a surge destructively through the Sears. If distance between any protector and Sears is maximum, then a surge should find earth easier via the building's single point earth ground. They did not discuss the many important considerations necessary to make any protector effective. Most important is what does protection. That is never a protector. That is always what absorbs hundreds of thousands of joules - harmlessly. Single point earth ground. If the protector connects low impedance (ie no metallic conduit, less than 10 feet, etc) to earth, then the protector will earth direct lightning strikes outside. If located adjacent to the Sears, then it gives lightning even more potentially destructive paths through the Sears or other nearby appliance. The OP had damage because his earthing was insufficient or non-existent. Maybe one AC wire is earthed. All other incoming wires must also be earthed via the protector. Otherwise no protection exists. Telcos have a multi-million computer connected to overhead wires all over town. Suffers about 100 surges with each storm. And no damage. Why? They only earth 'whole house' protectors. The protector connects to earth 'as short as possible'. Telcos also want all protectors distant from electronics - up to 50 meters. Because that separation "increases" protection. All homeowners could learn this technology that was well understood and routinely implemented even 100 years ago. Unfortunately, too many are educated by advertising that sells ineffective protectors located adjacent to appliances. Ineffective and extremely profitable. That 10 meter separation is one of many critically important considerations for protection from lightning and other lesser surges. |
|
| westom wrote: "This author has cited those reasons repeatedly in other discussions in this thread." That author googles for "surge" in his never ending crusade to save the universe from the scourge of plug-in protectors. For real science, excellent information on surges and surge protection is at: The IEEE surge guide is more technical. westom wrote: Protectors do not protect by "blocking" or "stopping" or "absorbing", but westom can't figure out how plug-in protectors work. Clearly explained in the IEEE surge guide starting page 30. Plug-in protectors primarily work by limiting the voltage from each wire (power and signal) to the ground at the protector. The voltage between the wires going to the protected equipment is safe for the protected equipment. Both the IEEE and NIST must have been taken in by the "scam". Both say plug-in protectors are effective. (When using a plug-in protector all interconnected equipment needs to be connected to the same protector. External connections, like cable, also must go through the protector. Connecting all wiring through the protector prevents damaging voltages between power and signal wires.) Why 10 meters? A short branch circuit means that more energy can reach the protector, some which is absorbed in the process of protecting. The NEC says a 10m min branch circuit is required if the manufacturer requires it (285.25). This is the first protection device I have heard of that has the 10m limit. Probably means the ratings are low. If the modules are listed under UL1449 they can pass the tests with 10m of branch circuit. I assume you are measuring 25 ft along the wire. |
|
- Posted by bus_driver (My Page) on Fri, Jun 29, 12 at 12:44
| No response from Chamberlain and at this point, I do not expect to receive one. This Chamberlain protector says that if it fails due to multiple or overly large surges, it still permits door operation. So installing it near the service panel increases the chance that a surge would destroy the effectiveness of the device. Logic tells me that if the protector does get destroyed by a surge, that portion of the surge is dissipated before it gets to the door operator. Article 285 of the NEC applies to permanently installed Surge Protective Devices (SPD) and while this is a plug-in, the functional effects should be the same. Now I must decide if these should be used at short distances from the panel since the NEC does not apply to plug-in devices. Thus far, I see no potential harm from using them. |
|
- Posted by don_1_2006 (My Page) on Fri, Jun 29, 12 at 16:07
| I see no harm either. Don't give up on Chamberlain. |
|
| > This Chamberlain protector says that if it fails due to multiple > or overly large surges, it still permits door operation. Obviously. Destructive surges are hundreds of thousaands of joules. That protection is maybe hundreds of joules. A large surge means the protector must disconnect as fast as possible. Leaving the door opener still connected to AC mains and that surge. Protector disconnects as fast as possible. Door opener is left connected. Sometimes, a tiny protector circuit does not disconnect fast enough. Then a fire can result. For example, melbourne architect in "Safety Switches / Surge Protection" at describes a protector that created a fire in an Australian fire house: ramjet33 on 6 Jun 2012 in "My 110 Tall had a fire over the weekend!" describes how the protector on his aquarium system almost killed his family: Norma on 27 Dec 2008 "The Power Outage" also describes the danger: Protection means you know where hundreds of thousands of joules dissipate. The always required short (low impedance) connection to earth. Effective protectors are located distant from appliances to make typically destructive surges irrelevant. Near zero surges (hundreds of joules) are already irrelevant due to protection already inside every appliance - including that door opener. Effective protectors are located distant from appliances and as close to earth as possible. Otherwise it must somehow block or absorb that energy without creating a fire risk. |
|
| > NEC applies to permanently installed Surge Protective Devices (SPD) and while > this is a plug-in, the functional effects should be the same. NEC says nothing about surge protection. NEC is only about human safety. It only defines connections for human safety. Transistor safety is completely irrelevant in that code. Transistor safety means both meeting and exceeding what code requires. |
|
- Posted by bus_driver (My Page) on Fri, Jun 29, 12 at 19:40
| For one to discount completely the potential effectiveness of surge protectors, and beyond that to suggest that they add to the potential hazards from surges, one would first have to assume that in the absence of such a protector, no damage or hazard would occur from an electrical surge. Some surges simply overwhelm all precautions that may have been taken. One of my properties experienced what I believe to be a direct hit by lighting. Buried wires to a well with submersible pump simply disappeared and the dirt over them was thrown for considerable distances. Parts of the wooden building were blown off. The electrical panel looked like an explosion had occurred. The pump was ruined. But I remain convinced that surge protectors do help in some instances, far more than those in which they would create problems. |
|
| bus_driver wrote: "Article 285 of the NEC applies to permanently installed Surge Protective Devices (SPD) and while this is a plug-in, the functional effects should be the same." You are correct on permanent wiring. For plug-in, if not installed according to manufacturer's requirements the UL listing is voided. I expect the only problem would be shorter protector life than you might get with a longer branch circuit. westom wrote: The NEC has a chapter on surge protection. westom wrote: UL has, since 1998, required thermal disconnects for overheating MOVs. None of westom's horror stories say a protector was made after 1998, or even that it was UL listed. One horror story did not even involve surges. One was Australia. westom wrote: The author of the NIST surge guide investigated how much energy might be absorbed in a MOV in a plug-in protector. Branch circuits were 10m and longer (10m again), and the surge on incoming power wires was up to 10,000A . (That is the maximum that has any reasonable probability of occurring and is based on a 100,000A strike to a utility pole adjacent to the house in typical urban overhead distribution. Only 5% of strikes are stronger than 100,000A.) The maximum energy at the MOV was a surprisingly small 35 joules. In 13 of 15 cases it was 1 joule or less. (Neither plug-in or service panel protectors protect by absorbing surges. But they absorb some energy in the process of protecting.) One reason the energy is so small is that at about 6,000V there is arc-over from service panel Plug-in protectors with far higher ratings than 35J are readily available. A plug-in protector with high ratings and wired correctly (as in my first post) is very likely to protect from a very near very strong lightning strike. What protection you get from the Chamberlain device depends on its ratings. Direct strikes to a building require lightning rods for protection. You can believe westom, an internet nut that compulsively posts that plug-in protectors are "scams". Or believe the IEEE and NIST surge guides. Both say plug-in protectors are effective. |
|
- Posted by bus_driver (My Page) on Sat, Jun 30, 12 at 13:28
| Chamberlain did respond. Part of the response is pasted below. "Recently you requested personal assistance from our on-line support center. Below is a summary of your request and our response. Thank you for allowing us to be of service to you. Thank you for contacting Chamberlain Technical Support. Below is a response to the inquiry you recently submitted on our website. I apologize for the confusion on installing the surge protector.That paper that was inside of the packaging was some sort of typo. Please just go by the instructions that came with the surge protector. You can throw that smaller piece of paper away. Again we do apologize for the confusion. Please let me know if you have any other questions or need further assistance. Scratching my head. The extra insert was written by someone, printed by someone and inserted in the package by a directive from someone. It was an issue for at least one person in a position of authority. But the answer really says go ahead and use it per the main instructions. |
|
| bus_driver wrote: "Chamberlain did respond. I am impressed - I didn't expect a response. bus_driver wrote: If the surge module is UL listed (1449) or a UL "recognized component" my guess is the added instructions are required by UL. ("Recognized components" are marked "UR" with the letters run together, backwards, and italic. If not UL, I agree there still is a reason instructions were added. |
|
| Regardless of all confusion. Reality for over 100 years was this simple. A protector is only as effective as its earth ground. Eliminate myths that promote protectors without earth ground. If a protector does not make a low impedance (ie 'less than 10 feet') connection to earth, then it does not protect from typically destructive surges. 'Whole house' protector and earth ground are always found in every facility that must never suffer damage from a direct lightning strike (ie munitions dumps, telephone switching centers). As in always. They don't waste money on protectors adjacent to electronics. They need protection. That means protector close to earth. And separation between the protector and protected electronics. A protector is only as effective as its earth ground - where hundreds of thousands of joules are harmlessly absorbed. Adjacent to a garage door opener means it can earth that surge through the opener. |
|
| westom wrote: "A protector is only as effective as its earth ground." Airplanes regularly get hit by lightning. westom wrote: If westom could read and think he could find out how plug-in protectors work. Clearly explained in the IEEE surge guide starting page 30. Both the IEEE and NIST surge guides say plug-in protectors are effective. Missing - any source that agrees with westom that plug-in protectors are a "scam". westom wrote: Apparently the Chamberlain module is a "scam" too. |
|
| Understand that bud is here because I am here. He is my personal troll. His job is to lie - to protect sales of scam protectors. The IEEE, NIST, and all other professional organizations say protectors without earth ground do little to protect from typically destructive surges. bud knows most will not read what the NIST, IEEE, etc say. Only hear his vitriolic attacks. For example, on page 17, the NIST says why a protector adjacent to appliances (ie door opener) is ineffective: >A very important point to keep in mind is that your > surge protector will work by diverting the surges to > ground. The best surge protection in the world can > be useless if grounding is not done properly. "Useless" because it must somehow absorb hundreds of thousands of joules when adjacent to a garage door opener. View specs on any protector that does not have a dedicated earthing wire. Hundreds of joules will magically make a surge (hundreds of thousands of joules) just disappear? So bud makes subjective claims. Never posts numbers. Never posts spec numbers from any plug-in protector. Since he does not promote a completely different device - the 'whole house' protector - then he must make subjective claims while posting insults. His IEEE citation - page 42 figure 8 - shows what happens when a protector is too close to appliances and too far from earth ground. It earths a surge 8000 volts destructively through a nearby TV. bud's job is to create confusion. So he says TV2 should also have a plug-in protector. IOW you must also have plug-in protectors on every bathroom GFCI, digital clock, dishwasher, and air conditioner. What is the most important appliance during a surge? Smoke detectors. According to bud, you must spend $thousands by putting obscenely profitable protectors even on every smoke detector. Meanwhile, the IEEE (like all other professional organizations) says any nearby appliance may be a victim when the protector is too close to appliances and too far from earth ground. Exactly what the garage door opener sheet suggested. The other completely different device does, according to an IEEE Standard, "99.5% to 99.9% protection". At best, a protector adjacent to appliances will do 0.2% protection. Spend $25 or $100 per appliance for ineffective (0.2%) protection? When one 'whole house' protector costs maybe $1 per protected appliance? In some facilities, an employee could be fired for installing what he promotes. They need protection - not profit centers. Every facility that cannot have damage ALWAYS earths 'whole house' protectors. Because no protector does protection. Because an effective protector ALWAYS makes a low impedance (ie 'less than 10 foot') connect to what does the protection. Single point earth ground. Where hundreds of thousands of joules are harmlessly absorbed. And without a massive profit margin that pays bud's salary. Every responsible oraganization cites earthing for protection. Either a surge is never inside the building. Or it is hunting for earth destructively via appliances. Nothing inside a house will stop that hunt. As in nothing. In some cases, a protector adjacent to a garage door opener can even make damage easier. Page 42 figure 8. The reason why informed consumers locate a protector as close to earth as possible. And also want that 30 foot separation between protector and the garage door opener. Telcos want their 'whole house' protectors up to 50 meters distant from electronics. Why do telco $multi-million computers suffer about 100 surges with each thunderstorm? And no damage? The protector is as close as possible to the earthing electrode. And up to 50 meters distant from electronics. That is well understood engineering. That a sales promoter must deny to protect his salary. |
|
| westom wrote: "Understand that bud is here because I am here. He is my personal troll." Westom googles for "surge" and is here because bus_driver said the magic word. Westom is on a crusade to save the universe from the scourge of plug-in protectors (irrelevant to this thread) and compulsively posts his drivel all over the internet. westom wrote: Lie #1. westom wrote: Lie #2 westom wrote: Lie #3 westom wrote: Lie #4 westom wrote: Lie #5 westom wrote: I don't say TV2 should have its own plug-in protector, the IEEE surge guide does. What a radical idea. With minimal mental abilities westom could discover what the IEEE guide says in this example: It is simply a lie (#6) that the plug-in protector in the IEEE example damages the second TV. westom wrote: The NIST surge guide suggests most damage is from high voltage between power and phone/cable/... wires. That would be TV and related and computer and related. westom wrote: Lie #7 westom wrote: That is apparently a religious belief (immune from challenge) for westom. For real science read the IEEE and NIST surge guides. Both say plug-in protectors are effective. |
|
- Posted by bus_driver (My Page) on Thu, Jul 5, 12 at 13:29
| Any surge protector for residential use must be connected to the service ground, which must in turn be connected to Earth. No argument there. And it is beyond argument that residential protectors are intended to shunt to ground (Earth, as the Europeans use the term ) any voltage on the ungrounded circuit conductor(s) which exceeds about 170 volts RMS for the time period in which it exceeds 170 volts RMS. Short and straight grounding conductors are highly recommended, but as with so many things in life, if what you have is not so ideal, you go with that. So tom, we do get it. |
Please Note: Only registered members are able to post messages to this forum. If you are a member, please log in. If you aren't yet a member, join now!
Return to the Home Repair Forum
Instructions
- You must be a registered member and logged in to post messages on our forums.
- Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review the contents and make changes.
- After posting your message, you may need to refresh the forum page in order to see it.
- It is illegal to post copyrighted material without the owner's consent.
- HTML codes are allowed in the message field only.
- No advertising is allowed in any of the forums.
- If you would like to practice posting or uploading photos, please visit our Test forum.
- If you need assistance, please Contact Us and we will be happy to help.