Grounding a new building

[kbsparky]

We are preparing a quote to wire up a new radio station transmitter building.

The site crews have already installed what appears to be a ground ring around the building foundation --- a complete circle of #2 solid wire, with several ground rods exothermically connected to an existing grid at the site. This grid goes as far as even bonding the metal chain-link fence posts!

I figure that all I need to do here is connect my GEC to this grid/ring for my grounding electrode system. I figure I do NOT need any more ground rod(s).

Sound right to you?

 

[ceb58]

We are preparing a quote to wire up a new radio station transmitter building.

The site crews have already installed what appears to be a ground ring around the building foundation --- a complete circle of #2 solid wire, with several ground rods exothermically connected to an existing grid at the site. This grid goes as far as even bonding the metal chain-link fence posts!

I figure that all I need to do here is connect my GEC to this grid/ring for my grounding electrode system. I figure I do NOT need any more ground rod(s).

Sound right to you?

That's about it. When we build a new site that is how it is done. One contractor dose the grounding grid and the other contractor that installs the meter/disco hooks onto the grid.
I will give this advise. Hook onto the grid with a cad weld. We have a site where the contract elect. drove two 3ft rods and ran to the meter base. Aside from the violation of the g rods they did not hook onto the grid. The site took a lightning hit and fried around $5000.00 worth of parts in the ATS and gen. They are now on the hook for the repair. The whole idea is to have a single point grounding system.

This grid goes as far as even bonding the metal chain-link fence posts!

Yes, and if you stand still long enough you will get bonded

 

[chris kennedy]

Yes, and if you stand still long enough you will get bonded

LOL:grin:......

 

[cadpoint]

Does the Spec's of the job state that a chemical test be done on the earth / ground that the Ground ring is laying in and is there some QA on the ground ring that is installed by others?

Did the master of the Ground ring get their work inspected?

I've watched and witnessed these beautiful's before they scare me... :grin:

 

[kbsparky]

The site is owned by the loco poco, and they were the ones doing the inspections. Seems that they have a substation nearby and much of their main communications go through the tower on the site. They certainly don't want THAT to fail!

It was their specs that had to be followed, much more stringent than the NEC.

I had the site crew leave me a tail of the #2 solid conductor sticking up near the service equipment for connection to the grid. Crimped and cadwelded to the ground ring, for a good secure connection.

FWIW, they also required 4 tails sticking up from the grid -- these tails are installed vertically inside the building at each corner to minimize any lighting intrusion that might occur.

 

[ceb58]

The site is owned by the loco poco, and they were the ones doing the inspections. Seems that they have a substation nearby and much of their main communications go through the tower on the site. They certainly don't want THAT to fail!

It was their specs that had to be followed, much more stringent than the NEC.

I had the site crew leave me a tail of the #2 solid conductor sticking up near the service equipment for connection to the grid. Crimped and cadwelded to the ground ring, for a good secure connection.

FWIW, they also required 4 tails sticking up from the grid -- these tails are installed vertically inside the building at each corner to minimize any lighting intrusion that might occur.

They are more than likely following Motorola's R-56 standards for communication buildings. The tails coming into the building will go up to a grounding halo that will run around the inside of the room. All conduits, panels,equipment racks or any thing metal will get bonded and tied to the halo.