Direct Bury Ground Rod Clamp History

[tom baker]

I started in the electrical trade in 1978, at that time we used a two screw zinc ground rod clamp and left the ground rod with 6" above grade.
That was a code violation unless it was a ten foot rod.
Then someone developed the direct bury ground rod camp, so we could meet the code requirement of a ground rod with 8 ft in contact with the soil.
What lead to the development of the DB clamp? Was it some sharp manufacturer? Or due to the violations from not having a ground rod with 8 ft in contact with the soil?

 

[Dennis Alwon]

I suspect that inspectors got together complaining about the rod being above ground where it was subject to abuse & unsightly. The manufacturers listened and came up with a fix. Manufacturers often get a bad name but they do want to make something they can sell so they do listen. If the demand is there they will make it.

Of course, this is all guess work. They may be the ones who forced the CMP to require it but IMO, that was a good move.

 

[tryinghard]

Just wonder: if a 4'er could be tested at say 15 ohms could be acceptable? Never know how long this resistance would last though but we don't know this with 8'ers either. I think the manufactures were pressed by insustry as whole to make something to enable compliance with the whole 8'er.