OTA antenna grounding question

[Z06_Pilot]

hey folks,

so, I have my Winegard 1080 on a 10' tripod mast in the middle of a flat part of my roof, along with some wireless weather equipment.

put it up a week ago when i got my Dish Network installed. reception is perfect and stable on all channels.

now I need to ground. here's my plan, looking for advice.

1. grounding coax. the dish installer ran the dish coax into the basement to a grounding block with a wire attached to the ground that runs into my electrical box. I thought I would do the same thing with the OTA coax. anyone see an issue with putting the grounding block for the coax inside the house rather than outside jusst like the Dish installer did?

2. mast grounding. I was just going to attach a #8 copper wire to the bottom of my mast with a lock strap from the hardware store, across about 8' of my roof, then straight down the side of the house behind the downspout, and attach directly to my electrical service grounding rod. total copper run, about 20'.

does this make sense?

thanks!

 

[Houston]

Z06,
It's always a good idea to ground !
Excuse for the cut and paste, but here's some parts you might consider in your project...

++++++++++++++
GROUNDING:
Though all locals do not require Grounding, it is a very good idea to enhance the Electrical protection of your system and other components, with a combination of these very important items …
Ground Block*: OR Surge Protector (both not necessary)
System Surge Protector*:

Some Locals require a minimum size of 8 gage wire for Grounding. (check your local codes)
And one of the following:
Ground Rod (4’):
(for exterior Grounding)
Pipe Clamp:
(Exterior or Attic)
Copper Clamp:
(For clamping on a Metal Beam/Structure/RV)
Above required for basic Mount/Mast grounding (30’).
Use Surge Protector for enhanced component protection.
The above Surge Protector is different from one listed below.
.* = Insertion of these components, will require the use of an additional piece of Coaxial Cable,
OR, the existing Cable can be cut, and two additional “F” Connectors^ installed, PER ITEM.

Component Surge Protector**:
(End of Line/at Component)

.** = This Surge Protector goes directly on Antenna Input of a Component. Use as many as necessary/you want.
You may use both System and Component Surge Protectors to further enhance the protection of the complete system.

Rod Clamp:
Ground Rod Clamp
++++++++++++
This was a blurb I wrote for another Post somewhere, but you may can use or get an idea from the parts list.

I think the Dish Guy took the easy route, putting the Wire inside. It's not a good idea, and if you can, keep everything from the Antenna/Dish, down Leads, Blocks to Ground Wire to Clamp and Ground Rod outside. As you come out of the Block(s), put a gentle Drip Loop before you enter the house. I'd re-do your Dish if it were me.

When a bolt hits, there a very likely spray of sparks, and I'm sure you wouldn't them bouncing around inside your house.
Good luck.

Have a good Day !
S.W.

PS: All those parts above are links to show what the part is/looks like. They aren't showing up very well on the Post, just run your Cursor over the text, and the links then should show up in red.

 

[roashru]

If you decide to get lightning arrestors get a real one with f connectors:

F-Female to F-Female 0-3 GHz 90V Lightning Protector - AL-FFFF-9 < Link

.

 

[JB Antennaman]

The ground should be run with as short of a wire as possible with no bends of more then 45 degrees.

The lightning will look for the shortest route with the least resistance.

When installing a antenna, it is the same as a used car lot.
Location, location, location!

Sometimes the difference between good reception and great reception is as little as 4 feet.

If you have to use a ground stake other then the utilities - you must connect the two with a buried #8 AWG wire.

You do not want the lightning to come in one side of the house and leave out through the other.

Most lightning strikes do not physically involve the antenna.

If you think about it, there is millions of miles of utilities wires strung across the United States. Your antenna might be 6' long.

Most times the lightning will strike the utility lines and will cause a power surge.

http://www.tech-faq.com/whole-house-surge-protector.shtml

A whole house protector will short out the power surge and protect valuable equipment such as your television, refrigerator, microwave oven, furnace, AC etc.
Leviton Whole House Surge Suppressor / Surge Protector 51120-1 - Smarthome

Here is one example.

 

[Z06_Pilot]

thanks for the replies guys.

the best place to put my antenna was on the 10' tripod mounted, 1 1/4" mast my weather station was already mounted to. easy to get to for service, but high enough to get fantastic HD reception on my locals.

so I had to run the ground wire from the mast across my roof-no choice. i ran it along the same route as the coax from the antenna, and they diverged at the house entrance. I actually terminated the mast ground #8 solid copper wire onto the same grounding rod as my electrical service uses. I just added a 2nd ring lock to the ground rod. the mast ground wire is a 40' run. i used just a couple of wide-arc bends.

I terminated the antenna coax on a grounding block, and used a 12" #8 copper wire to attach to the ground wire going into my electrical service box.

I think I did the best I could given the antenna location requirement, and based on everything I have read, I believe I am ok......don't like that ground wire run across about 15' of roof, but......

thanks everyone!

Jeff

 

[foxracing]

Just my 2 cents but:

Grounding is unnecessary. I install professionally and while we are required to ground, most jobs I go to I do NOT ground. I have had no problems or complaints from customers. I have never grounded any antenna at my house, personally, and have also never had problems.


What makes no sense is how if your grounding it outside, there is still the option of a surge protector for inside the house. How does the surge protector's function differ from the ground block outside of the house? Hm, just read Houston's post! Well In that case, I would just buy a surge protector and be done with it if your dish was over say 20 ft from where your electrical service box was.

But, since you did ground, that was the best for you to do. Pretty much every installer will run a copper ground from ANY point at the customer's house to the service ground.

 

[breaker1nine]

Don't let grounding give you a false sense of security. I have rolled on several lightning strikes. All the ground wire does is leave a long black mark along the area where it was attached and all of the electronics still get fried. Get a good surge protector, some come with insurance. Don't mess with the grounding. If you do ground that antenna, just run copper straight down from the ground block on the exterior to a ground rod, or wherever you won't mind having a black streak after a lightning storm.

 

[Z06_Pilot]

agreed, I'm not going to lose sleep over the grounding situation.

Yesterday I grounded the antenna and mast the best I could given it's position and the information I have gathered on this site and others....

for the better part of the first 40 years of my life, I lived in homes in Tennessee and Ohio that had roof mounted antennas that were never grounded, and we never, ever experienced any lightning or damaging electrical discharge issues.

I have PURE AV power conditioners as well as APC surge suppressors attached to all my A/V equipment, and APC UPS systems for my DVR's to allow them to continue recording during a short duration power outage(30 minutes or so)

thanks!

Jeff

 

[Houston]

Lightning - From Three Directions

foxracing,

Shame on you for not abiding by those totally inappropriate Codes, with their inadequate parts requirements.

There are three types of Strike...

1) A Direct Strike to your Dish/Antenna:
breaker1nine hit it pretty much on the head "all of the electronics still get fried".
With this type strike, there's hardly anything you can do to protect yourself and your equipment, other than spending thousands of dollars on a major Protection System.
You don't have a single piece of wire in your house, which is large enough to carry the Current from a Direct Strike, and if one hits, there is a great possibility of fire, and some physical shock, just cause you're there, regardless of where in the house.
Arrestors are the item to use here, are usually destroyed, and "may" provide you with some reasonable protection.

2) A Strike on the Power Line, somewhere else away from your house.
In this case, the Grounding of your Antenna/System is not all that big of an issue.
I still support System Grounding, but, the "danger" here is coming in through your Electrical Power Supply Lines, and, the best way to treat that situation, is at the Entry Box.
Westinghouse, Federal, Square-D and others, make a Surge Protector which mounts directly into your Box, just like a 220v Breaker. Using one of these catches the surge before it enters ANY circuit of your house. Keep in mind, your Sat/OTA stuff is not the only vulnerable equipment you have.
Though these items are sorta pricey ($75-$150) they are much more maintenance free, and come with an Insurance Policy as B19 has mentioned.
Individual Surge Protectors may used in this case, but, you may have to use several, to cover the equipment you have.
A well maintained Ground Rod for your Household Electrical System, is very necessary here !

3) A Strike near/in your area where the EMF is delivered through Free Air.
NOW, here's where you really need to ground your system !
If you don't give the voltage somewhere to go, it has no choice but to be carried via the Center Conductor and Shield of the Coax, directly down and into your stuff !
Agreed, that this supply of voltage is limited to your Sat or OTA equipment, but, who wants to replace that stuff, when a moderate amount of trouble and parts, should shunt the overage to ground.
Ground or Suppressor Blocks can be used outside, but the best place for the Suppression, is directly on the input "F" connector of the equipment. You thusly use the attenuation of the Coax, to reduce the load as it feeds in.

The difference between Grounding Bocks and Surge/Arrest Blocks/Modules.
Now, you can use both or all, but keep in mind that any "Suppressor", or "Attenuator" MUST have a physical connection to the Center Conductor of your down-lead, and in doing that, pulls off a little to a lot of your Signal Strength.
Ground Blocks are virtually free of any impedance to your Signal, they ground the Shield only.

Concerning that "Black Streak" down the side of your house that B19 mentioned.
This is going to seem like a "over kill", but, here's one way to deal with the Ground Wire when it's necessary to run it down the side of your house.
(This generally applies to Mast/Pole Mounts, but can be applied to Roof-mounts)

As your Antenna Down Lead arrives at the Eave of your house.
Use a Ground/Surge/Arrestor Block, your choice.
Allow a nice gentle Drip Loop of the Coax, and enter your house with that.
Install a Metal Electrical Conduit to take the Ground Wire from the Eave down below any flammable material. Just attach it to your House, DON'T ground it, it should be "free" from any contact which would influence the charge of voltage.
Use a Jacketed Wire (8ga or whatever is required) from the Block, into and down through the Conduit, and then out to the Ground Rod.
The Conduit could be 3/8" or 1/2" with some standard Mounting Clamps, or even a piece of Schedule 40 Pipe will do (kinda ugly though). But anything that will contain the molten copper, when a Direct Strike occurs.
The use of a Jacketed Wire, prevents the Conduit from being involved in the Ground Circuit, and allows time for the Strike Voltage to go to Zero, before the Copper melts.
We're only dealing with a couple nS here.

Z06_Pilot,
Sounds like you did a great job on your system.

Have a good Day !
S.W.

 

[vjeko]

Hi,
Hope you don't mind me bringing this thread to life again- it looks like the right
place to append a few questions.

I'm new to this forum, have electronics background but haven't been working in
the field for donkey's years and am very rusty and the grounding issue is
stopping me from going ahead with my home project (SAT dish -> 4 quattro
LNBs -> cascadable multiswitch -> 12 outlets). I have 3 phase power in the
house, so all equipment may not be on the same phase (not sure if this brings
up any additional possible problems)

Houston gave an extensive description of the grounding points to cover.
From the information, it looks like it is best for me to use the ground blocks on
the outside (doesn't attenuate the signal) and add a surge protector in the
electrical utility box where the fuses are. I'm OK with this but was wondering if
someone could explain whether additional grounding of the equipment inside
the house is needed and how it is done. I have attached a pic of a setup where
the equipment is grounded - it uses the"grounding block" type arrangement.
I'm thinking that grounding the coax at two ends (at the dish and at the input to multiswitch) will introduce a ground loop.

Secondly, I have the situation where :
- equipment (multiswitch etc.) is on ground floor
- want to mount dish/antennas on 2nd floor balcony
- roof is above 3rd floor (there is lightning grounding/protection on the roof
connected to 3 corners of the house - not to the corner where the dish will
be(when you have no problems trust the electrician to create them for you)
There's metal drain pipe from roof to all 4 corners of the house.
To ground the dish/ground block, I need to pull ground wire from the roof down
to the second floor balcony - does this make sense/create any problems

 

[Tower Guy]

I have 3 phase power in the house, so all equipment may not be on the same phase (not sure if this brings up any additional possible problems)

Welcome to the forum. Three phase power was invented by Tesla, a Croat.

3 phase power works fine when the grounds are correct. The key is that neutral and ground can be connected only once in each building. If there are subpanels, the ground and neutral must be isolated in the subpanel. The antenna ground must be bonded to the power ground.

 

[Houston]

Vjeko,

I couldn't open your attachment, thus the trials of using a DialUp.
I have very little to ad to TG's informative comment.

Customarily, it is not necessary to ground twice.
If you do, just leave enough slack in the Cable, to remove the Block IF you have loop problems. Or, if this is inconvenient, use a Inline Connector (coupling) to just bypass (and remove) the second Block.

The Equipment will be grounded through the Shield of the Cable, and no further grounding of it is necessary.

Have a good Day !
S.W.

 

[vjeko]

Houston - much appreciated !,
hate that when you feel you need to ask a question but you've really been
sleeping in class or like me very rusty regarding hands-on work
- I checked all F-connectors on the multiswitch with a voltmeter and shield is
connected through i.e. no further earthing needed.

One thing which I didn't get feedback on - my "problem" of the nearest grounding
connection being 1 floor above the dish/on the roof (the lightning protection
which is connected to ground on the other three corners of the house) - any problem of pulling a
grounding wire UP to the roof (next to galvanized rainwater pipe) ? I know current
likes low resistance but was not sure how smart it is to have grounding going up
to the roof when lightning is hitting down. The galvanized rainwater pipe goes
from roof to ground but there is no grounding on the corner of the house
where the dish will be (many thanks to the electrician )

 

[dodge]

Just my 2 cents but:

Grounding is unnecessary. I install professionally and while we are required to ground, most jobs I go to I do NOT ground. I have had no problems or complaints from customers. I have never grounded any antenna at my house, personally, and have also never had problems.


What makes no sense is how if your grounding it outside, there is still the option of a surge protector for inside the house. How does the surge protector's function differ from the ground block outside of the house? Hm, just read Houston's post! Well In that case, I would just buy a surge protector and be done with it if your dish was over say 20 ft from where your electrical service box was.

But, since you did ground, that was the best for you to do. Pretty much every installer will run a copper ground from ANY point at the customer's house to the service ground.

I had an inspector fail an electrical inspection on a 4 unit apt because the directv installer didnt ground anything!!!!! Cost the owner 220 bucks!!!

 

[raoul5788]

Just my 2 cents but:

Grounding is unnecessary. I install professionally and while we are required to ground, most jobs I go to I do NOT ground. I have had no problems or complaints from customers. I have never grounded any antenna at my house, personally, and have also never had problems.


What makes no sense is how if your grounding it outside, there is still the option of a surge protector for inside the house. How does the surge protector's function differ from the ground block outside of the house? Hm, just read Houston's post! Well In that case, I would just buy a surge protector and be done with it if your dish was over say 20 ft from where your electrical service box was.

But, since you did ground, that was the best for you to do. Pretty much every installer will run a copper ground from ANY point at the customer's house to the service ground.

Hmmm, you say grounding is unnecessary, then you say you install professionally. Sorry, but you can't be serious! Grounding is part of a professional installation. You are not professional in any way with an attitude like that.