Need some help with grounding an antenna. Water pipe or other ground?

Closed Thread

  #1  
Old 03-06-14, 02:13 PM
Member
Thread Starter
Join Date: Mar 2014
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
Need some help with grounding an antenna. Water pipe or other ground?

I'm going to be getting an HD antenna. I have no issues hooking it up, connecting it to a grounding block, etc..

The issue I'm wondering about is where I should ground the antenna itself to.
I have 2 options with pics to show what they look like.

First one is the incoming water pipe. Right now the verizon phone box is grounded to it. This is the closest to where the antenna will be installed so I'm assuming this is where I should ground it. I'm putting the antenna on a j-pole that currently has a Dish Network satellite dish connected to it which was already here when I moved into the house. I never used it myself. I dont see proper grounding on the satellite dish and is leads nowhere but where the coax connections are at. This will all be removed with just the j-pole staying in place. I will be replacing all coax instead of reusing old ones.

The one thing I dont like about the pipe ground is the fact that whoever painted the house painted the darn ground. I also dont know if the copper pipe is all copper coming from the ground.

Name:  20140306_155732.jpg
Views: 7799
Size:  27.2 KB

The next option is the main ground where verizon fios and my main electric meter is connected/grounded to. This is further away from where the antenna will go. Its beyond a door about 4 and half feet away from the water pipe so the ground wire if it were to go here would be a longer run. I have no idea how deep this small rod goes into the ground as it goes under concrete, but since the electric meter runs to it, it has to be a decent amount. Its not very big at all as you can see.


Name:  20140306_155743.jpg
Views: 4508
Size:  33.7 KB


So my question is which would be the best route to go? Connect the antenna ground to the pipe or to the main ground and why? I'm guessing the main ground and not the pipe since I dont know if the pipe is all copper or not under ground and isnt pvc to copper.

Any help is appreciated.
 

Last edited by nightwolf2014; 03-06-14 at 02:44 PM.
Sponsored Links
  #2  
Old 03-06-14, 04:49 PM
Temporarily Suspended
Join Date: Jul 2008
Location: NY
Posts: 10,986
Received 0 Votes on 0 Posts
I really don't think it matters. Apparently, both choices are already functioning as grounds.
 
  #3  
Old 03-06-14, 04:56 PM
Member
Join Date: Mar 2010
Location: USA
Posts: 3,679
Received 30 Votes on 29 Posts
Run a #6 copper wire from the electrical system ground (grounding electrode system) to the antenna.

You can also drive a ground rod in the vicinity of the antenna but this ground rod should be connected (using a #6 copper wire) to the electrical system ground.

You can choose the most convenient point on the electrical system ground, for example anywhere on the fat ground wire run between the panel and a metal main cold water pipe close to where it exits the house underground.

Other devices needing grounding, such as a satellite dish, may be connected to this ground wire going to the electrical ground.
 
  #4  
Old 03-06-14, 11:13 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 54,184
Received 475 Votes on 445 Posts
When I install rooftop antennas I use #8 bare to a dedicated ground rod outside the house.
The idea is to keep the lightning/surge from entering the building.
 
  #5  
Old 03-07-14, 03:41 AM
Banned. Rule And/Or Policy Violation
Join Date: Jan 2010
Location: KS
Posts: 1,896
Received 0 Votes on 0 Posts
Nope, it's not. Lightning is going to follow copper wherever it wants. It's not going to stop at a ground block, because the ground block only grounds the shield.. The current is still going to follow the center conductor right through the ground block and right into your equipment. A gas-tube arrestor grounds the center conductor and will at least give your electronics a shot at survival - but even then its not a guarantee.

The purpose of the grounding block and mast ground is actually to drain the static charge from the antenna and mast in order to lower the risk of a strike happening in the first place.
 
  #6  
Old 03-07-14, 10:29 AM
Member
Thread Starter
Join Date: Mar 2014
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
Thanks for the replies. I decided against even using an antenna outside after all. I live in the lightning capital of the world and I just dont trust it even being grounded. I'll just get basic cable and not worry about it.
 
  #7  
Old 03-07-14, 11:23 AM
Banned. Rule And/Or Policy Violation
Join Date: Jan 2010
Location: KS
Posts: 1,896
Received 0 Votes on 0 Posts
And what do you think will happen when the lightning strikes a pole? In this day of digital broadcast, that is simply not a valid excuse to pay a cable monopoly $25 a month for what you can get for free.

Chances are there are far more likely (read: taller) targets for a strike around you.. Trees, telephone poles, flagpoles, etc. As I said, properly grounding it lessens the chance of a strike by draining the static charge that would otherwise attract lightning.
 
  #8  
Old 03-08-14, 08:56 AM
Member
Thread Starter
Join Date: Mar 2014
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
With an antenna I'll only get between 8 and 10 channels that are all pretty much the same, basic cable I'd get about 60 so although free its very limited. I might still go the antenna route. I'm really still undecided.

Could I run a ground to the water pipe and to the ground by the electric meter? or even a new grounding rod? Most videos I see on youtube have the antennas grounded a good 3 times besides the grounding block. I believe the phone line on my house is grounded on the water pipe and then at the meter.

I read on a few websites that a ground wire should never go at a 90 degree angle. If this is true then it will be very hard for me to run a ground to the electric meter without make a 90 degree bend at a point. It would have to run along the top of my house then down.

I'm also seeing conflicting information about where the grounding block should go. Some say by the antenna, others say right before the coax enters the house. Which is it or does it not matter?
 
  #9  
Old 03-08-14, 12:08 PM
Banned. Rule And/Or Policy Violation
Join Date: Jan 2010
Location: KS
Posts: 1,896
Received 0 Votes on 0 Posts
Oh ok I thought you meant 'broadcast basic', which the local cable co here charges $25 for and it's just the stuff you can get OTA (and it doesn't even include the digital subchannels like Ion, MeTV, local weather, etc)..

The ground block is supposed to go where the cable enters the house. The mast ground goes to the mast. As for what to use, you don't need to do multiples, but it wouldn't hurt anything. As long as it's a hunk of copper with 10 feet of ground contact (as long as it's not a gas pipe! ) it'll serve the purpose. If you do drive a new rod, it should be bonded to the rest of the system..

As for the 90 degree angle... I have never heard that. The only thing I can think of is they are advising against a SHARP bend because it stresses the wire. But you can route it however you need to using 'sweeping' curves. The minimum bend radius of copper wire is no less than 8x the diameter of the wire. That means for your #10 ground, you should imagine bending the wire around a piece of 3/4" pipe - you can't just kink it into a square angle.
 
  #10  
Old 03-08-14, 03:04 PM
Member
Thread Starter
Join Date: Mar 2014
Location: USA
Posts: 4
Received 0 Votes on 0 Posts
Thanks for all of the info!
 
  #11  
Old 03-09-14, 11:26 AM
Banned. Rule And/Or Policy Violation
Join Date: Jul 2009
Location: usa
Posts: 102
Received 0 Votes on 0 Posts
> I read on a few websites that a ground wire should never go at a 90 degree angle.

Some basic electrical principles make obvious why that is so true.

These same principles also apply to what you need learn even if not mounting a TV antenna. (HD antennas are nothing more than a TV antenna hyped with the letters "HD" to promote sales).

TV antenna must be earthed directly on a wire that is as short as possible. That wire must not have 90 degree bends, must be as short as possible (for low impedance), and have no splices.

Then an incoming coax wire from that antenna must route to where the Verizon and AC electric are earthed. The shield must make a low impedance (ie 'less than 10 foot') connection from the cable shield to this other earth ground. Using similar above requirements - no sharp bends, wire routed away from any non-ground wires, etc.

Shield must be grounded. But other electrical concepts say why the center core need not be. Yes, the center core could also be earthed by using a high frequency protector. A protector never stops or absorbs surges. Effective protectors only make a connection to earth when a wire cannot do what would be a superior connection.

From your pictures, I would not worry about a coax cable protector. Since what is more important, in your case, probably needs much more attention and upgrading.

Grounds (not protectors) protect transistors. Best protection is a hardwire from each wire inside every incoming cable to earth. But some wires cannot be earthed directly (ie your Verizon wires). So we do the next best thing. We make that same connection with a protector. What determines quality of that hardwire or protector protection? Single point earth ground.

Apparently you only have one earth ground rod. You are strongly advised (in your region) to expand that single point earth ground with, at minimum, additional ten foot earth ground rods. Especially is your soil is sand. Safety code requirements further define where (how far apart) additional rods should be places. All rods should be connected to that first ground electrode where Verizon, AC electric, and the TV cable also connect. That becomes the single point earth ground.

A protector is only as effective as its earth ground. Your Verizon box contains a 'whole house' protector. That protector, like all protectors, is only effective when connected low impedance (ie no 90 degree bends) to earth. Same applies to protection of all AC appliances. Your electric box or meter should have a 'whole house' protector that makes the same low impedance (ie connect to earth that is every foot shorter) connection to the same earthing electrode(s). If you did not install that most important device, then it probably does not exist. This paragraph should have major attention. Since what we do for that antenna also involves protection of every household appliance - including the air conditioner, refrigerator, clocks, dimmer switches, TV, and most important smoke detectors.

So back to the antenna. It must connect as short as possible to an earth ground. Then its coax cable must enter where a low impedance (no 90 degree bends) connection is to another earth ground that defines protection for every household appliance. The single point earth ground that (it looks like) needs to be upgraded. Since earth ground (not any protector) and low impedance connections (ie wire not inside a metallic conduit) defines that protection.

BTW, these concepts have been well understood and proven for over 100 years. Which, unfortunately, demonstrates how many never learn well proven science; are only informed by hearsay and advertising. The 'no 90 degree' concept is obvious from basic electrical concepts.

Same advertising hyped your antenna as HD rather than what it really is - just another TV (both analog and digital) antenna. This post includes what you should know and what is only known to the minority who actually do this stuff. Installing and earthing that antenna is easy. But appliances may be at much greater risk if that earth ground is not robust AND if your AC electric does not include a properly earthed 'whole house' protector.
 
  #12  
Old 03-09-14, 01:15 PM
Banned. Rule And/Or Policy Violation
Join Date: Jan 2010
Location: KS
Posts: 1,896
Received 0 Votes on 0 Posts
Sorry you wasted your time typing all that nonsense.. It's just not relevant to this topic. We are talking about a grounding an antenna mast and its coaxial cable, NOT a circuit trace in a high-speed supercomputer where Gaussian principles are a factor. All this conductor is doing is continuously draining a static charge. A right angle is NOT going to affect that in any way shape or manner.

Seriously, that is like saying you can't bend Romex at a right angle because it will affect how fast the light turns on and/or how bright it is when you flip the switch. There is absolutely NO measurable difference in impedance in a straight piece of #10 wire versus a piece bent at 90 degrees (or 360 degrees, or even 720 degrees). Inductance? Yeah, because what is an inductor but a coil of wire. But not impedance/resistance.

Furthermore, lightning strike current WILL flow through the ungrounded center conductor of a coaxial cable, through a ground block, and through any components that it needs to (blowing up your TV in the process) in order to find ground. "Protectors" are not active components either. Since you can not ground a signal conductor directly, surge protectors and lightning arrestors only conduct when the voltage is high enough to overcome their breakdown point (MOV and TVS surge suppressors) and shunt the current to ground, or ionize the gas capsule into its conductive state (gas-tube arrestor) and shunt the current to ground. There is no 'switching' or any other active circuitry involved (other than an optional monitoring circuit to detect failure, but that plays no role in the protection mechanism).

Once again, the purpose of the coaxial ground block and mast grounding of an antenna is NOT to protect the equipment IN a lightning strike (which is the common misconception), it is to lower the risk of the strike ever HAPPENING to begin with. Lightning is attracted to objects carrying a large load of static electricity, and draining the static from the antenna and mast makes it less attractive compared to other tall objects in the area.

For protection from an actual strike, you need a lightning arrestor, and that needs to be properly grounded as well.
 

Last edited by JerseyMatt; 03-09-14 at 03:14 PM.
  #13  
Old 03-09-14, 04:41 PM
Banned. Rule And/Or Policy Violation
Join Date: Jul 2009
Location: usa
Posts: 102
Received 0 Votes on 0 Posts
> We are talking about a grounding an antenna mast and its coaxial
> cable, NOT a circuit trace in a high-speed supercomputer where
> Gaussian principles are a factor.

Insufficient electrical knowledge has causeed you to waste badnwidth with a nasty reply. Posted were simple electrical prinicples you had to know before recommending.

For example Richard Harrision, another industry professional, describes why that current does not flow through a center conductor:
Coax, inside, rejects common-mode propagation of lightning energy. Coax, outside, needs good grounding to make a good path around (bypass for) protected equipment.
He then continues:
The equipment needs direct low-impedance grounding so that most surge energy is dropped across the coax, not the equipment.
Anyone making a recommendation must know what common-mode propagation is, why it is relevant, what is low impedance, why that is so important, and the most important part of any protection system: single point earth ground.

Nobody said anything about bending Romex to slow the speed of light. Basic electrical knowledge explains why sharp (90 degree) bends increase impedance. Electricians are only taught what connects to what. As technicians, electricians are not taught basic electrical concepts necessary to answer the OP's questions such as impedance, common-mode propagation, equipotential, and other first year electrical concepts.

A coax ground and mast ARE for surge protection (among other purposes). Rather than make accusations, apologize to the OP for misleading him, for not first learning this stuff, for attacking another who did this stuff for decades, ask to learn about electrical concepts that say why 90 degree bends are problematic, what impedance is, equipotential, why common-mode propagation is relevant, why coax cable must be grounded, and why the only relevant ground is single point earth ground. One must know all this stuff before answering the OP's questions.

A lightniing arrestor does not do protection. Earth ground is where hundreds of thousands of joules are harmlessly absorbed. A number necessary to answre the OP's question. Where do hundreds of thousands of joules dissipate? An arrestor without a *low impedance* connection to earth is ineffective.

Best protection is a wire to earth ground. An arrestor is installed only when a direct wire connection cannot be implemented. An arrestor is only doing what a wire would otherwise do better. Protection is defined by the only 'system' component that does protection - earth ground.

Ask to learn about how surge protection has been done for over 100 years. This science is that well proven even by that much experience. Same concepts also explain why 90 degree bends can compromise protection. Protection for the OPs antenna is based in concepts even taught in elementary science about Ben Franklin lightning rods.

OP must make a short connect from the antenna to earth. Then must route a coax cable to enter at the service entrance. So that coax's shield is connected low impedance (ie 'lsss than 10 foot') connection to single point earth ground. More important, the OP should also install a 'whole house' protector. And upgrade what actually will do his protection - enhance single point earth ground. Earthing ground to both meet and exceed what the National Electrical code demands.

And, of course, wire connections to earth obvious must not be inside metallic conduit, must have no splces, and must have no sharp bends. A connection to a safety ground wire inside Romex obviously is not earth ground. For many reasons including the above three. A lightning arrestor is only as effective as its earth ground.

Posted by this author is how professionals would make his antenna installation safer for both humans and transistors.
 
  #14  
Old 03-09-14, 06:29 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 54,184
Received 475 Votes on 445 Posts
The OP has stated that he will not be using an outdoor antenna at this time.

Thanks for all the well thought replies and I'll be closing it as it seems to have run its useful course.
 
Closed Thread

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: