ECN Forum Forums Code Related Discussion NEC & other Code issues 250.66 and Ufer

It would be a shame not to utilize that ufer. Would a one-shot Cadweld work for that #2 to #4 connection or are those only for rods. I know that Burndy makes the Hylink compression connectors that are listed for grounding, but I’m not sure if they make a #2 CU to #4 CU connector.

The inspector will never forgive you for your being right.

Overwhelmingly, inspectors only accept engineering handed down from higher authorities -- and a contractor is at the wrong end of the food chain.

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There once was a general forman, a true genius, he was...

He made the mistake of trying to help out green foremen, green superintendents...

The latter NEVER forgave him.

At the end, EVERYONE involved was fired: both genius and greenhorns.

The super ran off the genius -- too much of an intellectual threat...

Then the super blew up the entire job -- running everything 'backwards'...

( He hadn't a CLUE as to where the priorities were. )

This caused ALL of the subs ( that's an astounding achievement ) to lose buckets of money and chronically fail their inspections.

After creating an 'instant legend' -- subs would discuss the horror for many months afterward all over the greater metropolitan area -- he had the guts to request job recommendations from the very contractors he burned for big money. (!)

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Which is all to say: you can't afford to be right all the time; ESPECIALLY if you are. It drives the other guy crazy.

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As for the case at hand...

Check to see if the #4 solid GEC is bonded to the re-bar above the grade. This is VERY commonly done. If so, expose it and switch conductors.

We're starting to see epoxy-coated re-bar. It would make for a useless GEC element. The Code is going to have to address this ASAP.

The Code, especially the Handbook, should have a Table of GEC Elements.

Within that table Ufers, Ground Rings, Ground Rods would be spelled out in crystal clear terms.

System elements that are required to be bonded in, if present, should be detailed.

The Grounding Path and the Elements that need to be Bonded to it so as to establish an Equipotential Plane can then be driven home.

And, lastly, some attempt can be made to clean up the difference between grounding and bonding.

( Grounding paths carry residual current ( +/- ) down into the Earth at all times. )

[ Bonding connections establish an equipotential plane for conducting elements -- with voltage potential flowing up and down -- normally, trivially -- with the bonded elements functioning in a Capacitive capacity -- NOT Conductive capacity. That is, they fill up with electro-potential and then bounce it back into the system - - just like a capacitor.]

The GEC into the earth, in contrast, bleeds electro-potential into the planet -- operating as a conductor for that purpose.

In Teslas words...

"The inspector will never forgive you for your being right."

Some of us are human, and have been known to make mis-judgements, bad calls, incorrect fails, being late for dinner, and who knows what else.

Any contractor, foreman, journeyman, apprentice, helper, etc. is always welcome to talk, question, debate, etc.

The Ufer is a required thing these days in Florida, at least around here. If you are using epoxy rebar they would have you dropping in a stick or two of uncoated for the electrode.

As I understand it, through the research done during the development of CEE/Ufer systems, it was determined that conductors larger than #4CU had no verifiable effect on increased ability to clear fault current, so this would seem to indicate that increasing the size of the GEC to the ufer is basically just giving the inspector a warm fuzzy feeling with no actual benefit to anyone.

How to keep the steel from corroding given the chemical exposure and likely levels of electrical current during storms (they have those in Florida)? My guess would be that titanium nitride would work great since it bonds well to steel, resists corrosion well enough for medical implants (unless heated to 800C), and conducts electricity well enough for tiny electrical circuits (unless chilled to near absolute zero) despite being chemically a ceramic. Of course it is expensive.

http://en.wikipedia.org/wiki/Titanium_nitride

They allow the turned up rebar connection inside a wall with a cover over it in most jurisdictions here. That #4 copper pigtail had a bad habit of disappearing, either by job site damage or just theft.

This is a typical Ufer