Lightning arrestor grounded to the mast?

[kc8qln]

My coax goes into my house almost immediately after the tripod. There is only 4 feet of cable from the Tripod to where the coax enters the house. So the lightning arrestor has to be on the roof, very close to the antenna & tripod.

If my mast & tripod are "already" properly grounded, can I simply ground the lightning arrestor to the mast/tripod with a short #6 copper wire and clamp or screw?

Thanks

 

[OceanaRadio]

My coax goes into my house almost immediately after the tripod. There is only 4 feet of cable from the Tripod to where the coax enters the house. So the lightning arrestor has to be on the roof, very close to the antenna & tripod.

If my mast & tripod are "already" properly grounded, can I simply ground the lightning arrestor to the mast/tripod with a short #6 copper wire and clamp or screw?

Thanks

Sir, by asking asuch a question, it lends doubt as to whether the rest of your system is "properly grounded" as you assert.

In the condition you described, the coaxial arresstor should always be mounted directly to a conductive mast, and either become part of or be as close as possible to the bonding conductors that ground the mast/tripod, etc.

A single bonding conductor and single ground rod is never acceptable for earthing an antenna/mast system on the roof of a structure or dwelling. A minimum of two bonding conductors each with its own ground rod is required for any roof appurtanance that requires lightinng protection. These should traverse and terminate at opposing ends of the structure if only two ground rods are used. All ground rods on the property must be bonded together, including the one that serves the structure's AC entrance panel. That bonding, both across the roof and at ground-level should use #4 or larger conductors.

A second coaxial lightning arrestor at a single point ground connection adjacent to the connected equipment is advisable. The above apply even if you choose to disconnect equipment when not in use. Installing a mast/antenna on a roof requires specific precautions that affect the entire structure and all wiring inside it. When properly installed, it will offer some protection to the roof from lightning. Done improperly, it is a liability that could even void insurance coverage since it violates electrical codes, at least in the U.S.

Hope this helps.

Jack Painter
Virginia Beach VA

 

[Yokoshibu]

Hey, I read the thread on the ground rod, I think you could get away with it but in addition I would run an additional #6 directly to the arrestor! but using the mast as a support is not such a bad idea as long as the mast isnt bearing a major load!

 

[Al42]

Hey, I read the thread on the ground rod, I think you could get away with it

You CAN'T "get away with" anything when you're dealing with lightning. If you establish a proper grounding system for the building (you can't establish a proper grounding system for one antenna - there's no such thing) the building *might* survive a direct lightning strike. If you're trying to "get away with it", figure out your next addrss now, because you'll be needing it. If you survive.

"Getting away with it" is playing Russian roulette with a 5 cylinder revolver with 5 bullets strapped to a stick of dynamite with the fuse lit. You're going to die, the only question is "when". DON'T play with lightning. Please.

 

[kb2vxa]

Hi all,

Forget all the CRAP you read on this and other forums, http://members.cox.net/pc-usa/station/ground0.htm is the real deal. Just the same there is no absolute guarantee, while broadcast and commercial installations get whacked every day and suffer no damage still I have seen lightning take out an entire complex.

To borrow a lyric from the Who;
I put up my antenna and play,
just like yesterday.
But I get on my knees and pray,
we don't get killed today.

 

[Yokoshibu]

You CAN'T "get away with" anything when you're dealing with lightning. If you establish a proper grounding system for the building (you can't establish a proper grounding system for one antenna - there's no such thing) the building *might* survive a direct lightning strike. If you're trying to "get away with it", figure out your next addrss now, because you'll be needing it. If you survive.

"Getting away with it" is playing Russian roulette with a 5 cylinder revolver with 5 bullets strapped to a stick of dynamite with the fuse lit. You're going to die, the only question is "when". DON'T play with lightning. Please.

Nothing will survive a direct hit. I was referenceing the mounting solution... duh of course a direct hit will melt the mast but with the ground rod directly under the mast I would bet its safe to say the lightining will leap through the antenna / arrestor to the rod... not like I have ever seen examples of that before. - after the copper incinerates the next best path is direct to the rod.... I can get away with lightning outside my house... its the inside I care about!

 

[prcguy]

I have equipment at several mountaintop sites in So Cal that get direct hits every year with no damage to equipment except for an occasional fiberglass Stationmaster antenna exploding on the tower. A properly designed building, antenna and electrical system can and does survive multiple direct hits somewhere, every day. However, it’s impractical to protect your HOME antenna from a direct hit even if you install ground rods, lightning protectors, etc, it’s only going to help reduce the chance of damage from a nearby strike. The NEC code is a good starting place to ground your antenna so you don’t create a shock hazard and beefing up from there can’t hurt anything as long as you understand it has limits. Last time I looked at the code you had to connect the antenna to the nearest electrical ground with no more than 20ft of #10 copper wire (or #6 Aluminum) and if you use a ground rod it has to be connected to the house ground with at least #6 copper wire. If someone says a particular device will protect your home system from a direct hit, forget it. A false sense of security can destroy lots of equipment, property or possibly KILL YOU. My home system has massive grounding for a residence but if there is a storm coming, I unplug everything!
prcguy

 

[Audiodave1]

Hi all,

Forget all the CRAP you read on this and other forums, http://members.cox.net/pc-usa/station/ground0.htm is the real deal. Just the same there is no absolute guarantee, while broadcast and commercial installations get whacked every day and suffer no damage still I have seen lightning take out an entire complex.

Excellent Article!!!!!!
Looks like I have some work to do...good thing copper is cheap ...yea, right.

Dave