4wire for 3 wire system

[Daja7]

odd question and i should know this, installing a service upgrade and customer has 4 wire ser cable he wants me to use. from meter to panel only requires 3 wire SE. is there a code that prohibits this?

 

[Dennis Alwon]

Just cut off the equipment grounding conductor

 

[102 Inspector]

Actually inspected the same thing yesterday on a detached garage. New service with 4-wire, installer used neutral and grounding conductor as parallel. Connected to grounding lug in meter base(utility does not ground from meter base) and connected to terminal in load panel. He said the guy at the supply shop had a short piece he would give him. Less then 2 feet total distance.

 

[Dennis Alwon]

Actually inspected the same thing yesterday on a detached garage. New service with 4-wire, installer used neutral and grounding conductor as parallel. Connected to grounding lug in meter base(utility does not ground from meter base) and connected to terminal in load panel. He said the guy at the supply shop had a short piece he would give him. Less then 2 feet total distance.

Did he use a double lug or put them both under the same lug? What size wire? Can't parallel under 1/0. I wonder if the equipment grounding conductor is 1/0 or larger

 

[kwired]

Just cut off the equipment grounding conductor

Or only connect one end then it is still a grounded shield of sorts.

 

[Dennis Alwon]

Or only connect one end then it is still a grounded shield of sorts.

That is what I suggested in post #2

 

[kwired]

That is what I suggested in post #2

Sorry, I did not see your implied "just one end" in there, next time type a little slower.

 

[Dennis Alwon]

Sorry, I did not see your implied "just one end" in there, next time type a little slower.

I read yours wrong thought you meant disconnect the egc

 

[kwired]

I read yours wrong thought you meant disconnect the egc

You would have to connect it before you can disconnect it:lol:

sorry, guess I'm a little ornery this morning.

 

[Daja7]

thanks, that is what i thought. If used as a parrallel do they not need to be the same size. just an aside :?

 

[102 Inspector]

Conductors were #2 alum and were not connected under a double barrel lug. This meter base had the neutral lug in the center of the meter base with a grounding lug beside it. The panel had the neutral connected at normal location, with 4th wire connected to grounding busbar with approved lug. Did I miss something with paralelling less than 1/0. Never even thought of it while I was standing there. First mistake this year.

 

[infinity]

Did he use a double lug or put them both under the same lug? What size wire? Can't parallel under 1/0. I wonder if the equipment grounding conductor is 1/0 or larger

Even if #1/0 or larger the two conductors in parallel would need to be the same size and have the same characteristics, like both being insulated or bare.

 

[Dennis Alwon]

Even if #1/0 or larger the two conductors in parallel would need to be the same size and have the same characteristics, like both being insulated or bare.

Good point.

310.10 (H)

 

[Daja7]

so bottom line is nothing prevents using 4 wire for 3 wire application if i leave both ends of the spare wire disconnected and taped up?

 

[kwired]

so bottom line is nothing prevents using 4 wire for 3 wire application if i leave both ends of the spare wire disconnected and taped up?

Wouldn't even be a problem if they were not taped.