Ground Plate Connectors

[topgun1986]

I'm looking to install my 40' Rohn 25G soon, and have some questions regarding grounding the tower feed lines going into my shack. I have seen plenty of pics with a solid 2" by 8" copper bar at base of tower, with connectors (SO239, N connectors, etc) attached to it, somehow "built into" the copper plate, or at least they look like there integral with the plate. Could someone please point me in the right direction of where I could purchase some of these fittings that attach to the copper plate?

[mmckenna]

Check out Harger. They make a lot of grounding equipment and are a great source for this sort of stuff.
Ground Bars & Accessories
Tessco sells their stuff on line. Newmar marine also makes some grounding equipment for their telecom power systems. We've used some of those at work also.

Rather than using connectors "built in" to the ground bar, the standard, at least on the commercial side, it to use coaxial grounding kits that wrap around the outer shield of a cable that has had a bit of the outer jacket removed. The kits come with the stuff you need to seal it back up. The bond around the outer shield has a length of #6 stranded copper wire coming off of it that you crimp a lug onto and bolt to the grounding block with stainless steel hardware. This keeps your cable run in tact without having to add additional connectors. At the building entrance end, the poly-phaser or similar protection device is bolted to the ground plate at the entrance. This is also a common point to switch to a more flexible cable to run to your equipment. I've got some pictures of those sorts of set ups if you would like me to post them.

[topgun1986]

Thanks for info. Yes, if you could post pics, that would be great.

[mmckenna]

Here is the tower base ground:


Here is a picture of the building entrance ground with the protectors mounted on it:

[n5ims]

There are these (Bulkhead Mount Coaxial Couplers - Provides Feed-Thru Mounted Connections in Panels and Bulkheads) if you want to build your own.

This article (near the bottom) has a writeup on what they did to ground the coax cables at the base of their tower. Building a ham radio tower

[mmckenna]

Originally Posted by n5ims

This article (near the bottom) has a writeup on what they did to ground the coax cables at the base of their tower. Building a ham radio tower

Interesting article. It may have left some stuff out. While it's certainly OK to install the lightning protection at the tower base, unless he has them at the entrance point into his building, he's leaving the door open for issues. Lightning strikes, even near by ones, can travel through the ground and love to find buried cable, conduit or not. The lighting protectors should be at the entrance to the structure to properly protect the system, not just at the base of the tower. Hopefully he did that and just didn't post the pictures.

[mmckenna]

Here is a clearer photo of the protector mounting at one of my sites. This is where the cables enter the building from the roof.



Getting everything grounded well to a common point makes a big difference.

[k3td]

Very nicely done - congratulations!