I know it`s not by code but can you ground a satalite dish to a bare ground in a lite fixture in the attic?How does lighting enter a building and what`s the best way to keep your stuff from getting fried during an electrical storm? Bill
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I don't think you would want to create a direct path for lightning to get into the house electrical system. If you were to provide a ground for the dish, it would need to be a large wire (like #4 or so) and go directly to a ground rod.
"When asked if you can do something, tell'em "Why certainly I can", then get busy and find a way to do it." T. Roosevelt
this one could go on forever......
Isn't the dish plastic? Why would lightning strike the dish?
If it does, thousands of volts will be coming down both sides of the coax cable, which will then find it's way into the house electrical system thru the satelite box, the tv chassis and everything else that is connected to the satelite.
I would look at pulling the threat of lightning to a rod, away from the dish. Give the lightning an easier path to ground while leading it away from the dish.
If you are talking about a monster metal dish, I would consult the manufacturer.
But isn't he really just wanting to provide the same lightning protection for his dish as he already has in the grounding system for his household wiring? As I understand it, that's one of the purposes for the separate ground....to provide an easier, more direct path for lightning than the neutral or hots that go to each appliance or light.
May be 4Lorn or a dish installer will stop by.
"Isn't the dish plastic? Why would lightning strike the dish?"It is either metal or metalized plastic.It has to reflect RF and plain plastic won't do that.
Why not mount the dish on the ground? Unless it's to clear obstructions. I laugh whenever I see them mounted high here with plain view from ground level. LNBs occasionally go bad and in snow country, snow can accumulate on the dish. Much easier to maintain at ground level.
So unless you HAVE to mount it on the roof, I would say move it to ground level where it's easier to ground properly and much LESS likely to get struck by lightning in the first place.
My dish has been in at ground level for 8 years now, grounded via a grounding block and copper grounding rod driven in beside the pole. NOT bonded to house ground. I was only concerned with dissipating static before the line enters the building, not so much with anything else.
No grounding at all will protect you from a direct strike. And as another poster pointed out, tying into a light fixture in the attic is asking for trouble in the event of a direct strike. You are more vulnerable from the phone line anyway in most cases.
my $0.02, worth what ya paid for it.
> Why not mount the dish on the ground?
Bingo. The signal's already gone 22,300 miles. The height of a house won't help it at all.
-- J.S.
It'll keep the dog from peeing on it.
If ignorance is bliss why aren't more people
happy?
If there's a clear path to the satellite, it's not a problem unless you don't want to see the dish in your yard. Also, it's harder for vandals to mess with it and if it's in a cold climate, it's harder to clear snow off of it.
"I cut this piece four times and it's still too short."
dish is metal
The absolute minimum is to have a grounding block where the coax enters the house, with a wire from that block running outside to a reliable ground.
happy?
The purpose of a satellite antenna ground is not to "attract" lightning but rather to raise the level of the ground potential to the antenna so that is does not "stick up" any higher than anything else from an electrical potential viewpoint. The other reason is to allow the metal or metal plated dish reflector to operate more efficiently as a focused mirror of the electrical "waves" coming down from the satellite.
To repeat, the best is to keep the dish near ground (dirt)level so it can be serviced easy. That extra 30 feet the signal travels from the satillite will not be noticed. And, always use a grounding block (lightning arrestor) on the coax before it enters the building. The dish SHOULD have come with the special block. Ground wires from lightning arrestors should be run in as straight a line as possible to a ground rod. Lightning does not like to turn corners or go around obstructions like masonry chimneys.
How does lightning enter a building? Any way it can! Usually through a wire, but through the roof is also popular. It entered my house by striking trees in the yard, going through the ground (earth) to the "Invisable Fence" for my dog , back to the transmitter box in the garage and then entering the 120 volt garage circuit, then back through the service entrance to ground rods. Took out smoke detector, two modems in computers (back in dial up days) one motherboard and three TV's had diodes blown in them. And this was with a lightning rod system that performed flawlessly! I say that because the trees were struck (three of them in a group) and not the house. Thus lightning rods do not attract lightning. As mentioned by me on another thread, if they did the military would not use them to protect explosive storage areas. They give lightning a proper path to earth.
So NO, do not ground the dish in the attic. Too much to fry on the way down the electrical circuit.
Frank DuVal
You can never make something foolproof because fools are so ingenious.
A brand new, just-moved-into $300K (big for here) house burned down last summer when lightning hit a tree, got into the propane gas line near the tree, and followed that into the house.
If ignorance is bliss why aren't more people
happy?