Thread: Lightning Fix
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Old 14-Nov-2010, 6:40 AM   #25
westom
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Join Date: Nov 2010
Posts: 10
Quote:
Originally Posted by jp2code View Post
Also, in your Duke Energy pictures you keep linking, I must state again that my home was built in 1955 and therefore was built with the older code 2-wire conductor. ...

My house is wired mostly like the Wrong image on the left. Power comes in on the East, Phone comes in on the West, CATV is on top of the house connected to OTA NTSA Broadcast Gods. It is possible that inside the house the Phone wires tie into the Power's ground, but there is NO EXTERNAL WIRE that connects the two systems like shown in the Right (i.e. Center) image.
OK. Provided were meat and potatoes. Better information means a more useful reply.

Does not matter if a home is three wire installed in 2010 or two wire installed in 1930. Safety grounds inside a house (if existing or not) are irrelevant to surge protection. Wall receptacle 'safety' ground is not 'earth' ground. All homes - 1930 and 2010 - required earthing the breaker box and a telephone 'installed for free' whole house protector. Those earth grounds had to exist. In your case, each is using a separate ground. But the grounds do (must have at some point) exist.

Older homes (your vintage) used the water pipe. That was and is not sufficient for earthing. Install dedicated earthing - ie what Duke Energy demonstrates or something less. At absolute minimum, ten foot copper clad ground rods as sold in Lowes, Home Depot and most any other hardware store. Do this for both human safety and for transistor safety. Duke Energy demonstrates how to upgrade human safety (most minimal) into earthing also for transistor safety.

Well, the installers screwed you. Set your home up to suffer surge damage. In 1955, home electronics did not exist. Even phones had no at risk devices. So installers were never told how to properly earth a home. Transistors arrived about 1970. So finally around 1985, installers should have known better. Either way, you are stuck to fix your earthing.

Either a phone wire must be rerouted to enter the building adjacent to AC electric. Ie phone wire routes outside and around a building to enter with AC electric. Or do what Duke Energy suggests. There are no alternatives to the only proven technology for surge protection. Every wire inside every cable must first connect to single point earth before entering. Duke Energy's 'right' (kludge) or 'preferred' solutions are necessary.

Now the OTA antenna. An in-line surge protector either blocks TV signals. Or does absolutely nothing. It is obviously not within feet of earth ground. And is not blocking TV signals. So it does nothing useful. To provide surge protection, it must block the surge and therefore also block radio signals. If you have TV signals, then you know the protector is doing nothing useful - not blocking anything.

Treat the antenna different from its coax lead. If necessary, each gets earthed at separate locations. An antenna must be earthed directly. That 150 foot (indirect) ground wire is a lame attempt at safety ground. If the antenna is 30 feet above earth, then a ground wire must go 30+ feet to earth - as short as practical. Duke Energy suggests connecting the antenna's ground rod to the AC electric ground rod via a buried wire.
Then two separate earth grounds become one big single point earth ground. But the antenna earth ground wire must not carry lightning all over the house - ie under eaves - to potentially create a house fire. Lightning strikes the antenna. You do not want the full lightning bolt traveling 150 feet underneath eaves? Of course not. You want lightning to go only 30+ feet - the shortest path possible - into earth ground on a wire that has no sharp bends, no splices, etc. At least a 6 AWG (almost quarter inch thick) bare copper wire.

As I understand it, the Channel Master pre-amp is on the antenna mast. Leave it there.

RG/6 coax lead must connect to the same earth ground used by AC electric. A connection typically with 12 AWG that connects the coax shield, less than 10 feet, to earth ground. If necessary, the RG/6 replaces that 150 foot ground wire under eaves. Or it goes down that house side to be earthed (ie using Duke's suggestion) before rising up to enter the house where it already enters. But the antenna lead must be connected short to single point earth ground somewhere between the pre-amp and where it enters the building.

BTW, coax wire inside HVAC ducts is a code violation if coax is not fire rated.

Is a power strip/surge protector connected within ten feet of single point earth ground? If not, then remove it. It is wasted money, weakens TV signals, and, well, appreciate what might happen as demonstrated by Norma's example on 27 Dec 2008 entitled "The Power Outage":
> Today, the cable company came to replace a wire. Well the cable man pulled a wire and
> somehow yanked loose their "ground" wire. The granddaughter on the computer yelled
> and ran because sparks and smoke were coming from the power surge strip.

Either a protector connects a surge to protection (earth ground) or the protector does nothing effective. Your power strip is not connected to earth ground for too many reasons. So how does its few hundred joules make hundreds of thousands of joules disappear. Norma demonstrates what too many power strip protectors actually do.

As GroundUrMast suggests, a splitter relocated near the breaker box (and with its own 12 AWG wire 'less than 10 feet' to the breaker box's earth ground is the entire surge protection for TV cable. Far superior to anything that a power strip protector would ever do. The coax gets earthed by a ground block just outside. Or via a splitter located just inside.

Better is to use a ground block outside so that earth is before the Channel Master power supply. A surge incoming on the coax gets earthed before seeking earth via a Channel Master supply. If using the splitter as an earthing connection (which would be after the supply), then that supply must also be earthed by being powered, for example, from a receptacle attached to the breaker box. So that the Channel Master supply is also connected within feet of earth ground.

Of course, your breaker box also must have a 'whole house' protector.

Grounding to a furnace does nothing useful. Simply puts energy inside the house to hunt for earth destructively via appliances. That energy must be earthed where the cable enters the building. Furnace is not earth grounded. Furnace is only safety grounded. As noted before, those are electrically different grounds.

Your descriptions are superb. Quite easily understood. Demonstrates why your antenna could easily be and is not presently earthed. Helps to explain a reason for your confusion. Earth and safety grounds are electrically different even if one eventually connects to the other. Most do not grasp the difference. Also useful was the construction date. If anything was connected after 1955, when would also be useful.

Locate the telephone 'whole house' protector that is always installed (for free) by the telco. Either it is a post 1980 NID box. Or an originally installed and now obsolete 'carbons'. Either way, it must have an earthing connection even if installed in 1930. Inspect to learn what you have.

Carbons: http://www.inwap.com/inwap/chez/Phoneline.jpg
NID: http://www.citynet.net/supportdp.cfm?article=8
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