I know there should be exactly one main ground point that everything connects to.
400 amp service provided by 2 200 amp main disconnect panels
Ufer ground
two ground rods
I understand there should be one continuous wire from one of the 200 amp panels to closest ground rod and terminated at second ground rod.
Does second main disconnect panel connect to ground on first main disconnect panel or first ground rod?
where does ufer ground connect?
Replies
Why ground rods, much less two, with a Ufer ground electrode?
Now service enterance is one of those things that regardless of what the NEC says that there is a lot of local variations and requirements. Both by the power company and by the local inspectors.
You don't have to make the connections in the panel.
This graphic shows where you can make them.
In a case like your you might want to bond the ground electrode to the neutral at the meter.
http://forums.taunton.com/n/docs/docDownload.aspx?guid=BA0499FD-47D6-4F66-8E90-33144FED6633&webtag=tp-breaktime
There are few things worse then engineers, trying to be lawyers, thinking they can write! The NEC is a prime example.
There is but one "grounding electrode." Everything else is a "supplemental electrode." All of your supplemental electrodes need to be connected to the grounding electrode.
Now, this does not mean they need to be physically connected directly to, say, a ground rod. There is nothing wrong with them connecting to the ground bus of a sub-panel, or the neutral buss of the main panel, etc. The goal is that all the grounding means be at the same potential.
For all practical purposes, the Ufer is a vastly superior ground to any rod. Indeed, I suspect that a ground rod placed less than 6 ft away from the foundation that contains the Ufer will provide essentially no improvement in the 'ground.'