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post #1 of 21 Old 03-28-2014, 08:26 PM - Thread Starter
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Hope this is the right forum. Need help on grounding a rooftop tv antenna and couldn't find forum close!

 

The basics are: want to install a HD tv antenna, tripod mount on the roof! The only ground I know of is the main electrical panel ground at the other end of the house. To add to this, the cable has to enter the house at the mid point of the house before splitting to 3 tv's. I know the antenna has to be grounded and the cable needs to be grounded so am I going to have to install ground rods where the ground wire comes off the roof and another where the cable enters the house? And tie them into the main entrance ground? Is this what's called bonding? Water pipes can't be used because thet've been changed to plastic. Any help would be greatly appreciated! If this is the wrong forum, please redirect! Thanks!

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post #2 of 21 Old 03-29-2014, 05:55 AM
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You are on the right track. If you drive a separate grounding electrode (rod), you have to connect that electrode to the building's grounding electrode system.

So yes, you bond the new electrode to the existing system. I need #6 Cu. to do the bonding. You can bond the new electrode to an existing electrode (rod), the service mast (raceway), or existing grounding electrode conductor.

From what you've said, it sounds like you will be running a lot of #6 Cu.

810.21 of the NEC is where you want to look.

Tim
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post #3 of 21 Old 03-29-2014, 09:46 AM - Thread Starter
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Thanks for your reply! After years of paying big bucks for Direct I'm cutting the cord and trying to do this antenna thing by myself. So, if I understand it right, I will need separate ground rods for the tripod and cable entrance? Also, in trying to get away from hours of hammering, I did a YouTube search  and found ways of using water to help install the rods! I also found people who thought the end result unsatisfactory due to not enough actual ground contact? Do you know anything about it? Sure would be a lot easier! I understand the rest (preamp, distribution amp, quad guard cable, etc,) of what I need to know, I think!

 

Again, thank you very much!

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post #4 of 21 Old 03-29-2014, 01:06 PM
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The ground rods aren't too bad to install. Just rent a rotary hammer from HD and you can drive it in 3 min.

You can bond the ground block to the #6 or to the ground rod. You don't need to run a separate wire to the service, as the #6 is running back there already.

Once you run the #6 back to the service I don't see how you could have unsatisfactory results. If you just installed the rod and didn't bond it to the existing grounding system then yes, you will have a problem (difference in potential, for one)

Tim
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post #5 of 21 Old 03-29-2014, 05:43 PM - Thread Starter
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Man! Now I am confused!

 

ok! If I run a ground wire from the antenna to a ground rod, then run a groundwire from that rod to another ground rod where the rg6 goes into the house (with the rg6 grounded there) and then run ground wire from the second rod to the house groundrod, I should to OK?

 

The ground wire path would be---antenna (to) goundrod (to) groundrod @(grounded) rg6 entrance (to) house ground. This could conceivably be done with one  continuous ground wire? If this is wrong, can to guide me a source of info (suitable for a newbee).

 

    I can't thank you enough for your help!  Tom

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post #6 of 21 Old 03-30-2014, 04:07 AM
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From the antenna to the rod ("electrode") must be a minimum #10 Cu.

From the ground block ("antenna discharge unit") to the rod must be a minimum #10 Cu ("grounding conductor").

From the new rod to the existing grounding electrode system must be a minimum of #6 Cu ("bonding jumper").

Recommend you run from antenna to rod and terminate with a listed ground clamp. If you are installing 2 rods run #6 from clamp on first rod through clamp on second rod, then on to existing system. Alternatively run a piece from first rod to second rod, then second piece from second rod to existing system. Clamps are listed for a single wire, so you will need to purchase a second clamp for the second rod if you go this route.

Run a #10 from the ground block to either the rod (terminate with a separate clamp) or to the #6, whichever is more convenient.

As always.. check codes, not an electrician, local regulations may vary.. and so on.. and so forth..

Tim
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post #7 of 21 Old 03-30-2014, 06:10 AM - Thread Starter
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OK! Got it! Thank you very much!

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post #8 of 21 Old 03-30-2014, 06:42 AM
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One other thing- if you get the ground clamp that is a single cast piece with a bolt in one end, the bolt gets tightened against the rod. The wire is sandwiched between the rod and the "pointy" end of the clamp.

The wire does not go between the bolt and the rod.
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post #9 of 21 Old 03-30-2014, 07:48 AM - Thread Starter
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Yes, thank you! I noticed that as I was doing my research and it came in handy! Walking around the house, planning and measuring yesterday, I happen to see the clamp had broken on the house service ground rod! Have no idea how long it had been like that but I purchased a new clamp and fixed it! I figure that could have been tragic!

 

I was going to use #8 solid for all the new ground wiring but after reading your post I'll use #6 and #10 as recommended! There's a guy on line (thewireman) who seems reasonably priced!  We had an outside antenna years ago that was destroyed in a storm and when the "professionals" hired by the insurance company "fixed" it they simply clamped 10 gauge wire to the mast and ran it to the outside faucet! To make matters worse, we're on a well with plastic pipe! Anyway, I had figured #8 was fine if they used #10.

 

It might be tricky bending the wire around two-90 degree corners but I read it's fine if the bend radius is at least 6 inches!  Just for looks, I'm going run the ground wire from the tripod down the house through plastic pipe! I don't see where it said you can't! The house is white and it'll help hide it! I'm going to paint the tripod and mast brown to match the roof and I'll be sure to mate bare metal to bare metal!

 

I think, with your help, I've got it covered! TKS.

 

                    Tom

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post #10 of 21 Old 03-30-2014, 08:57 PM
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To be clear - you most run a 10 awg (may differ by locality) from the new ground rod to the existing ground rod. You're better off running a cable from the new mast ADU to the existing ground rod.

Keep researching.

Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. -Buddha

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post #11 of 21 Old 03-30-2014, 09:15 PM
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Ground rod to ground rod is supposed to be a #6.

CIAO!

Ed N.
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post #12 of 21 Old 03-30-2014, 10:51 PM - Thread Starter
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All three ground rods will be connected with #6 AWG solid copper using ground rod clamps! Tripod will be grounded to first (new) ground rod with #10 AWG copper wire using ground clamp! Co-axle cable will be grounded at second (new) ground rod using #10 AWG copper wire and grounding block at entrance to house! So all three rods are connected and the tripod and cable are grounded.

 

I think that's right! Unless I hear different that's how I'm going to do it! I read where people make the mistake of not bonding ground rods so while this may not be perfect I think it will work and I'm ahead of some folks, safety wise! I hope! The #10 isn't solid core but should be fine!

 

Thanks guys!

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post #13 of 21 Old 03-31-2014, 02:39 AM
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Quote:
Originally Posted by egnlsn View Post

Ground rod to ground rod is supposed to be a #6.
Thank you.

Good resource from Mike Holt www.mikeholt.com/mojonewsarchive/GB-HTML/HTML/GroundingSatelliteDishandLead-InCables~20020303.htm

I think that 6 AWG bonding conductor needs to be solid copper.

If the 2nd rod isn't bonded correctly, you're increasing the likelihood of a lightning strike.

No attic to run a grounding conductor from the ADU to the house ground? Easier and safer than dealing with this 2nd ground rod.

Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. -Buddha

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post #14 of 21 Old 03-31-2014, 03:42 AM
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Solid or stranded, insulated or not. The only difference would be making sure the clamps are listed for stranded conductors.. which is usually the case.

Tim
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post #15 of 21 Old 03-31-2014, 07:56 AM
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I think the bonding AWG 6 wire needs to be copper, and not copper clad or aluminum. Solid or stranded, insulated or not - agreed.

I have read mention of ground rods being sunken every 20 feet, but haven't seen a code for that.

17 AWG steel messenger/carrier wire is usually easier and cheaper than a second ground rod.

Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. -Buddha

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post #16 of 21 Old 03-31-2014, 11:08 AM - Thread Starter
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Neurorad, I'm not sure I want a ground wire running through the attic if lightning strikes and I'm relying upon work that I've done! If what I've posted is a safe, even if more expensive, way to ground things I think I'll stick with that! The #10 wire I'm going to order is stranded, the #6 is solid so I'll make sure the clamps are for stranded (TKS Mr. Tim). I read that stranded is more prone to 'break down (?)' but more actual contact area to carry a charge.

 

My granddaughters boyfriend's buddy use to install directv and is between jobs! I'm thinking it may be better to hire him than to trust my 64 rear old body up on a roof. Do these installers know their stuff or is it 10 mins of instruction and they get handed a wrench? Actually, this is starting to make me nervous! It started out so simple! This can't be that complicated!

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post #17 of 21 Old 03-31-2014, 01:46 PM
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The 17 AWG steel messenger wire is usually run from the ADU to the house grounding block, and provides an outlet for static discharge from the dish and mast. The 17 AWG wire acts as a fuse, in case of a direct lightning strike.

I would hang the dish on the side of the house, if possible.

Before you buy anything, do more research.

Here is another old thread to chew on. http://www.dbstalk.com/topic/199170-dish-far-from-house-ground/

How deep does the bonding 6 AWG need to be buried, for code, if at all? Do you need additional ground rods every 20 feet?

I don't know a great deal about proper grounding - 'to code' - but I know a 2nd ground rod can be a setup for the propagation of nearby lightning strikes into your house, if not properly bonded.

Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense. -Buddha

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post #18 of 21 Old 03-31-2014, 05:18 PM - Thread Starter
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Supposedly, bonding wire should be at least 6" off the ground. I intend to use plastic P clamps to 'hang' it around the cinder block foundation! What the hell does Lowes call P clips? I've thought of every name I can think of to call them and Lowes gives me back 'nothing'! Playing around with the antenna today I received 12 excellent stations! This is just roped to a step ladder about 5 foot off the ground and no pre-amp. Now I'm

 getting excited. We should get at least 19 channels (as per TVfool) and even though there'll be duplicates, I'll be pleased. Should save big bucks over Directv. Does co-axle quad shield require different connects or just any F type? I ordered 100' w/ connectors on both ends but I'll have to cut it to ground it!

 

Everything I've read says not bonding rods can be worse than not grounding the antenna  in some cases!

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post #19 of 21 Old 03-31-2014, 09:03 PM - Thread Starter
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If I understand after watching Mike Holt video---

 

If the antenna is more than 20' from the house service ground you must use a grounding rod as close as possible to the antenna and bond it with #6 wire to the main house ground.

 

I could find nothing about every 20ft

 

The co-axial has to be grounded at it's entrance into the building to the main ground if possible and to a ground rod bonded to the main house ground if more than 20ft.

 

I think that's right!

 

So I think my set-up is correct!

 

1. antenna grounded from roof to 1st rod w/ #10 wire--

2. #6 wire used from 1st rod as bonding wire that is attached to --

3. 2nd rod at co-axial entrance to house--

4. co-axial is attached w/ grounding block--

5. #6 wire continues from 2nd rod to main house ground.

 

with all the research I've done I hope this is right but if not---please let me know.I've ordered all the wire--

 

100 ft of #6 AWG solid copper

 

25 ft of #10 AWG copper strand

 

100 ft of co-axial quad shield

 

   yet to buy--

 

2 - 8ft ground rods

 

3- 3/8" ground clamps

 

1- co-axial single wire gnd block

 

whatever I fasten the #6 up with to the cinder block

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post #20 of 21 Old 04-03-2014, 09:33 AM
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Just a quick thought, you mention an attic a few times, why not just install he antenna in the attic? Skips the grounding issues.

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post #21 of 21 Old 04-03-2014, 04:18 PM - Thread Starter
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I'd love to! But  the closest stations are 45 miles south and about 70 miles north-east and TVfool recommends not mounting in the attic! Bought PA 18 pre-amp so here's hoping. 

 

Bought plastic pipe today to hide the bond wire. All the wiring came today - and it's suppose to rain for the next few days! Still have Directv until June, plus I bought Roku to try (I'm keeping it), so no rush!

 

$15 Tivo                                

 

$6  Tivo mini

                                  vs                      $130 mo. DirecTv

$8  Netflix

 

$8  hulu plus                                                                 

                        

Hope it's worth it! Pay back ---- about 9 mos. or less! Unless I screw up the ground/bond and lightning hits!

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