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Mike, you state:
"E) Run in Straight Line. The grounding conductor must be run in as straight a line as practicable.
Author’s Comment: Lightning doesn’t like to travel around corners or through loops, which is why the grounding conductor should be run as straight as practicable."
So is this a mandate by the NEC or is it dependent on other issues. For instance, some home owners associations require specific satellite dish locations that require a longer run from the house main electrical box. Would this nec code require them to wave that policy and have the dish as close as possible to the main house box so as to have a strait and short a run as possible? t.j. Reply to this comment |
Reply from: Mike Holt How this rule is enfored is up to the authority having jurdisdiction. Reply to Mike Holt |
The original article has a little bit different wording that shows how the state was using scare tactics to make consummers think their houses were at risk.
"Dish Network customers at risk for electrical fires"
"The Minnesota Department of Labor and Industry is notifying 6,800 Dish Network customers from Rochester to the Twin Cities to St. Cloud that they could be at risk of an electrical fire during thunderstorms because of an improperly installed satellite TV dish. "
"No fires or injuries have been reported. However, the department randomly audited 100 Dish Network dishes installed in 2004 and 2005 by Galaxy 1 Marketing of Bettendorf, Iowa, and found 80 that failed to meet state electrical code requirements. Most failures involved improper grounding. "
"Dish Network's parent company, EchoStar Communications Corp. of Englewood, Colo., and Galaxy 1 Marketing did not return requests for comment Tuesday. "
"The risk of fire exists regardless of whether the antenna system is used, so turning off the system or having a dish that was never activated doesn't protect the homeowner, the department warned. "
http://findarticles.com/p/articles/mi_km4466/is_200605/ai_n16394019 Joel Reply to this comment |
In my area., Satellite Dish installations are one of the more obvious examples of 110.12 violations if nothing else. I happened upon your newsletter while browsing for any shared concerns regarding their shoddy practices not knowing about the AP report from Minnesota. I agree with Fred Marion that the "NEC should address accessible ground for a multitude of services to be available outside of the residence".
Jeff Meuse Hooksett, NH Jeff Meuse Reply to this comment |
Reply from: Mike Holt It will in the 2008 NEC. Reply to Mike Holt Reply from: Fred Marion In Kittitas County Washington, residential doesn't get a final Electrical inspection. Electrical panels are trimmed out and all ground wires are hidden from view. The inspection by Labor and Industries is done long before construction is completed while the ground rods are visible. This then meets the NEC 250.94 requirement . Somewhere the building code needs to address this as a inspection requirement for occupancy.
Fred Marion Cle Elum, Washington Reply to Fred Marion |
Why am I not surprised that a sub-contract installer with very little training should fail to ground anything properly.
I think 20% is very high, when you figure that those were probably accidental.
I wish that we had time to inspect phone, satalite TV, & CATV installations. Since the City I inspect for doesn't require any of the above to be necessary for occupancy of a home, they are never installed at the time of the Final. Gary Line Reply to this comment |
Reply from: Mark I asked my Minnesota cable company, Comcast, to bring my CATV grounding up to code. They informed me I was 'grandfathered' in and a change wasn't required but they reluctantly came out anyway after I complained.
After they completed the job, I inspected the work. They had run the CATV around the house to the main Service Entrance and had installed the correct CATV grounding connector but the 10 guage wire running from it to the main house ground wire had already snapped off at the CATV grounding connector. At the other end, they had attached the 10 guage to the house's main ground wire with a clamp that was clamped directly on the main ground wire. Unfortunately, the main ground wire had about 4 coats of paint on it which they just clamped on top of without cleaning it off. The Phone line had the same poorly bonded ground wire. Needless to say, I had to sand off the paint, reattach the wire and fix it myself. My call to Comcast was never returned. Reply to Mark |
This is in response to Bill Quaglia's posting.
Your grounding method of providing a separate ground rod will not meet code unless the dish ground rod is bonded to the main grounding electrode with a 6-AWG copper or equivalent, as per NEC 800.40 D. Separate ground rods not bonded to the main power grounding electrode will cause potential differences between their associated wiring systems. Which by the way may cause audible hum due to this condition. Jon Sandin Reply to this comment |
I whole heartedly agree that the satellite industry needs a training book. I also agree that these system need to be properly grounded, but using scare tactics. Come on that\\\'s BS. For those of you like the State of MN that think grounding will prevent fires altogether (isn\\\'t that what they are saying) I\\\'ve got news it won\\\'t So telling people their house will catch fire, and their equipment will blow up is just another Government agency lying to it\\\'s citizens Shame on You MN. Tell the Truth that Grounding is for Shock protection, static bleed, and does have some affect at lightning arrest, but it doesn\\\'t guarantee you won\\\'t have damage due to lightning. But the burning house has a greater affect that\\\'s why they use it eh?
The Timinator Reply to this comment |
Reply from: Mike Holt I personally think that the State of NM is doing a great job in alerting the industry. We have a serious problem with the proper grounding of communications systems, and if they are not properly grounded, there is a much great likelihood of a fire from a lightning event that doesn't hit the home.
I hope that other states take similar action.
Reply to Mike Holt Reply from: Joel Has there ever been a documented case of a house fire or personal injury due to a properly or even an improperly grounded satellite dish? I'd be curious to see any statistics. Reply to Joel Reply from: The Timinator Please explain further. This is completely untrue Mike. Yes there is a serious problem with grounding in this industry. Grounding is very important, but I have seen many lightning strikes that came in destryed the TV, satellite recever. The Fridge. The switch for the reciever. This came in from the powerline. Oh it fried the satellite system to. I have seen systems that were not grounded, and the same thing happened. Explain that. Again I don't disagree with making the system complient, but lying is unacceptable. This is ludacris that You and MN think that this will actully stop a fire. It can happen anyway whether it is grounded, or not. It's possible it may reduce it somewhat, but why not just say that. Reply to The Timinator Reply from: The Timinator MN is doing a disgrace to the community by lying they are not helping, but hurting this cause. That is the true tragedy here. I hope other States take action, but are honest about it, and tell of the shock hazard. Tell them it is nessesary for a Static, and Noise bleed. This crap agravates me to no end.
Reply to The Timinator Reply from: The Timinator Nothing can prevent damage from a direct lightning strike. But grounding with proper surge protection can help reduce damage to satellite and other equipment from nearby lightning strikes.
I just found this in your words. Why not tell this to the people. Reduce being the key word. They are saying that it will prevent it. That is completely false Reply to The Timinator |
I spoke with my Electrical Inspector about Article 250-94. He told me that it was up to me to make sure that the electrican provides access to grounding for CATV, phones, and etc. He wasn't going to worry about accessible grounding for other services.
As a side note I requested a # 10 ground wire for a residential interface from an electrician. He installed a #10 from an existing electrical outlet .
Sincerely,
Fred Marion Fred Marion Reply to this comment |
I had a Dish Networks technician come to my Sacramento home in August of 2003 where he tried to install the grounding wire from the antenna to my furnace outlet ground in the attic. He argued briefly with me when I told him that connecting this ground wire to my electrical grounding system was not code ant that it needed to be run to a separate grounding rod beneath the antenna. I explained that lightening arrest is much different than fault clearance. He disconnected the wire at my request and then said that he had to speak to his supervisor about returning to run the ground to an electrode.
In hindsight, I should have called his supervisor. In fact I will call today because they never returned to install the ground.
Best regards,
Bill Quaglia
Sacramento, Ca Bill Quaglia Reply to this comment |
Reply from: Jeff Meuse Bill Q - Nothing will survive a direct lightening strike, not even the ground rod. If a ground rod were ever struck by lightening the circuit breakers would cease to work. Without circuit breakers nothing would prevent wires from overheating and starting fires. Protective devices like UPS, power conditioners, voltage regulators, surge suppressors, etc., are totally ineffective when connected to defective grounding.
As the previous post mentioned, a second ground rod is required to be bonded to the existing ground system - - -provided the existing ground properly works ! Testing for faulty ground requires a $400.00 circuit analyzer to rule out bootleg grounds. A clamp on ground rod tester can determine if your ground rod even meets the NEC requirement of 25 ohms or less-the cost for one of those babies is around $1,500.00. I highly doubt a dish installer carries either of those and more improbable that he would know which end to hold it. and if he did he is even less likely to hold a license enabling him to correct the problem should he find one.
Ground rods are the backbone of what counts for effective protection against lightening strikes. Microprocessor based equipment manufacturers such as Ericsson, Lucent, Motorola and Nortel are known to void their equipment warranties at sites where the ground rod performance does not meet their explicit earth grounding requirements, typically 5 ohms or less. Residential & Commercial buildings need only follow the NEC code requiring ground rod resistance to be 25 Ohms or less. and not to the manufacturers low resistance standards. Even if the dish tech installed an additional ground rod and bonded it to the buildings properly working grounding system, it would likely take up to three 30 foot long ground rods pounded down into the water table to meet microprocessor based low resistance standards of less than 5 ohms resistance. Furthermore, resistance of ground rods is rarely tested by the electrical inspector, next to nobody meets NEC ground rod requirements (25 ohms or less), so power quality should never be assumed. It certainly wouldnt surprise me at all to discover that far more than 80% of the electrical inspectors (25 ohms or less) ground quality 'sign-off' were assumed.
Now, the NEC does not call for what is known as “low resistance electrical grounding”. These specifications are most often those of equipment manufacturers, power quality consultants or electrical engineers familiar with sensitive equipment’s grounding requirements.The NEC does not address the low resistance grounding or bonding requirements of the manufacturers' grounding standards for thier sensitive networked systems nor does it even address the testing of NEC compliant grounding beyond initial inspection. But that doesnt mean there wouldnt be hell to pay upon the discovery of some magnificent percentage revealing massive deficiencies in ground rod code requirements.
The point is, Dish intallers are expected to go back and properly ground their systems against a backdrop of an even greater percentage of failings to meet NEC ground rod code.requirements let alone low resistance standards.
Exactly how does anyone propose for dish installers or anyone installing microprocessor based equipment to actually meet the real requirements for grounding? Go back and run a #6 to a cold water pipe?
No doubt that'll make somebody happy but Id be included in that happiness too if EVERYBODY met code.- starting with a code enforcement department in charge of ensuring compliant ground rods !!
I'd have a better chance of winning the lottery than finding a compliant ground rod at your-name-here's home, Anytown, USA
Jeff Meuse
I Reply to Jeff Meuse Reply from: Mike Holt Jeff, just one quick comment. The NEC does not require the grounding electrode system to have a resistance of 25 ohms or less. This requirement (25 ohms or less) only applies if you are installing a single ground rod as the grounding electrode system, see 250.56. Reply to Mike Holt Reply from: Jeff Meuse Thanks Mike,
The 25 ohms or less rule only applies to the resistance of Rod, Pipe, and Plate Electrodes and if a single rod electrode fails to achieve 25 ohms or less it can be augmented by another rod or any other electrode listed in 250.52 A2 thru A7
When ground rod, (pipe and plate) electrodes serve as the buildings grounding electrode system as they often do, the National Electric Code requires them to have a resistance of 25 ohms or less.
Jeff meuse Reply to Jeff Meuse Reply from: Steve Klein How do I know what size groung plate to use for building ground? Reply to Steve Klein |
can you ground tv dishes directly to the ground bar, in an electrical panel thanks tom bush Reply to this comment |
Reply from: Mike Holt No. See the following from my textbook Understanding the NEC.
810.21 Grounding Conductors. The antenna mast [810.15] and antenna discharge unit [810.20(C)] must be grounded as specified in (A) through (K). Figure 810-8
Author’s Comment: Grounding the lead-in antenna cables and the mast helps prevent voltage surges caused by static discharge or nearby lightning strikes from reaching the center conductor of the lead-in coaxial cable. Because the satellite sits outdoors, wind creates a static charge on the antenna as well as on the cable attached to it. This charge can build up on both antenna and cable until it jumps across an air space, often passing through the electronics inside the low noise block down converter feed horn (LNBF) or receiver. Grounding the coaxial cable and dish to the building grounding electrode system helps to dissipate this static charge.
Nothing can prevent damage from a direct lightning strike. But grounding with proper surge protection can help reduce damage to satellite and other equipment from nearby lightning strikes.
(A) Material. The grounding conductor to the electrode [810.21(F)] must be copper or other corrosion-resistant conductive material, stranded or solid.
(B) Insulation. The grounding conductor isn’t required to be insulated.
(C) Supports. The grounding conductor must be securely fastened in place.
(D) Protection Against Physical Damage. The grounding conductor must be guarded from physical damage. If the grounding conductor is run in a metal raceway, both ends of the raceway must be bonded to the grounding conductor.
Author’s Comment: Installing the grounding conductor in a nonmetallic raceway, when the authority having jurisdiction judges that physical protection is required, is a better practice than using a metal raceway.
(E) Run in Straight Line. The grounding conductor must be run in as straight a line as practicable.
Author’s Comment: Lightning doesn’t like to travel around corners or through loops, which is why the grounding conductor should be run as straight as practicable.
(F) Electrode.
(1) The grounding conductor must terminate to the nearest accessible: Figure 810-9
a. Building or structure grounding electrode system [250.50].
b. Interior metal water piping system, within 5 ft from its point of entrance [250.52(A)(1)]. Figure 810-10
c. Accessible service bonding means [250.94].
d. Metallic service raceway.
e. Service equipment enclosure.
f. Grounding electrode conductor or the grounding electrode conductor metal enclosure.
(G) Inside or Outside Building. The grounding conductor can be run either inside or outside the building.
(H) Size. The grounding conductor must not be smaller than 10 AWG copper or 17 AWG copper-clad steel or bronze.
Author’s Comment: Copper-clad steel or bronze wire (17 AWG) is often molded into the jacket of the coaxial cable to simplify the grounding of the satellite dish by eliminating the need to run a separate ground wire to the dish [810.21(F)(1)].
(J) Bonding of Electrodes. If a ground rod is installed to serve as the ground for the radio and television equipment, it must be connected to the building’s power grounding electrode system with a minimum 6 AWG conductor. Figure 810-11
Author’s Comment: The bonding of separate system electrodes (building and radio and television equipment electrode) reduces voltages that may develop between the building’s power and the radio and television equipment grounding electrode system during lightning events. Figure 810-12
(K) Electrode Connection. Termination of the grounding conductor must be by exothermic welding, listed lug, listed pressure connector, or listed clamp. Grounding fittings that are concrete-encased or buried in the earth must be listed for direct burial and marked “DB” [250.70]. Figure 810-13
Reply to Mike Holt |
What's the most common problem, grounding?
I see this is a business opportunity for you Mike; you need to develop a class on how to install cable/satellite to meet code. As much as they charge for this stuff, they can afford to send their technicians.
Matt Matt Reply to this comment |
I find it disturbing that a state agency would scare the daylights out of consumers by telling them their house is at risk from lightening strikes by improperly grounded satellite dishes. Whether grounded or not, the same risk is there. There is no way to ground a dish to protect it from a lightening strike ! I have been on many a service calls where a properly grounded dish was hit by lightening and started a fire in the house, fried all connected electronics, etc. The MN letter is just a ploy to show that their liberal licensing requirements are justified. Total BS! They should appologize to the people!
Joel Reply to this comment |
Thanks Ed,
Seems this tidbit is overlooked by inspector if a final is required. During rough-in the bonding and ground rods are visible. In most cases the inspector signs off. When the house is finished and the Telco or CATV is installed, the ground is nowhere to be found. Another concern is the location of these interface boxes to the natural or propane gas line entering the residence.
That is another subject!
Fred Fred Marion Reply to this comment |
How can they say the repairs are to be made at "no" cost to the customer? Are they performing the repairs on their own time after regular business hours, no labor costs involved? These labor costs will be "rolled into" next years budgets which will hike up the operating costs. Then being disbursed to the customer thru rate changes. Hardly at "no cost to the customer" If these media companies had properly trained individuals and programs enabled to verify the integrity of the workmanship. Alot of these inadequacies might not exist. Cost cutting measures are killing the economy. Every aspect.....except the attorneys. Chris Thomas Reply to this comment |
As a licensed Sound & Video Contractor in the State of Connecticut. I appreciate the article on Dish Network's installations. I have also seen many installs in my area that do not conform to code. Two in particular in the condominiums where I reside. I seems the installer was to quick to get the job done, and on to the next one. He mounted the the dish (Antenna) to the plumbing roof vent pipe which is PVC except where it protrudes thru the roof. When the owners of the condominium units in question start getting roof leaks I wonder who is responsible?
I can understand why non conforming installs occur because the service providers only pays a flat rate on its installs usually to a sub contractor for the satellite service provider, who in turn wants to get the job done as fast as possible. This is what I refer to as the free installation provided by the satellite providers.
Installers who are licensed and SBCA certified are given training and instruction on how to properly install a system.
For my clients I explain what the free install is all about and inform them that I do not do free installs. I use better materials and perform the work to NEC standards and better.
In closing I would also mention that I had reported the sites in question to the state electrical board over a year ago and they were going to investigate them. To date nothing has changed they are still on the plumbing vent pipes and most or all the installs at our condominiums are not grounded to the main building ground rod as required by code. Jon Sandin Reply to this comment |
Even here in Erie, Pa. I see a lack of knowledge or mabe care about grounding of catv or even our phone supplier.
Ken KenHall Reply to this comment |
First as an Installer I meet the code, second finding a ground is next to impossible whith direct burial and PVC. Homes have stucco or rockery. Even the phone company isn't grounding many of their boxes in my area. I contacted LNI and ther attitude is that"We didn't say it would be easy".I really feel that the NEC should address accessible ground for a multitude of services to be available outside of the residence.
Fred Fred Marion Reply to this comment |
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