Gas line and electrical ground in same trench

[bob_mp]

Greetings,
I am building a 21x44 detached shop. The electrical drop goes to the meter main (320/400A) on the garage, with separate 200A breakers to the house and the subpanel in the shop.

I am planning on heating with gas. Here's the question:

Can the ground connection (1/0 Cu) to the cold water pipe share the trench with the gas pipe? If so, are there any limitations as to how close they can be placed?

I get why gas and energized circuits are disallowed. Is there a concern in this case.

Thanks!
Bob

 

[wyliesdiesels]

I don't see why this would be a problem since gas lines are suppose to be bonded to ground where they come into a building anyways.

The bond to a water pipe should be within the first 5' of the pipe entering the building so why are u running the GEC in a trench? Usually, a water line is bonded right near where it goes into the side of a building. Also, 1/0 cu seems a bit large for the GEC bond to the water pipe but I don't have my code book in front of me to check. I will look tomorrow when I get to work.

 

[Nostraquedeo]

Are you putting it in a trench for a ground ring?

 

[bob_mp]

Hi,
I understand the code to require a connection from the meter main ground to the cold water pipe, within 5 feet of where it enters the house.

The shop doesn't have water, so I understand I need to connect it to the cold water pipe entrance to the house (at the front). The gas mater is there as well. So I thought I'd stick them in the same trench.

As for the size, I think 1/0 Cu is required for a 400A panel. Is there a section of the NEC you can point me to?

Thanks,
Bob

 

[wyliesdiesels]

Sorry, I was to slammed today to look. And I leave all my code books @ work. I will look for u tomorrow...

 

[fireguy]

Building and Fire codes vary from place to place. What is code in the OPs area, may not be code in any of the respondents areas. Call the local building department.

 

[bygasper]

Where I am, 18" of soil is required between any of the electrical main components in the ground and other utilities.

 

[wyliesdiesels]

Hi,
I understand the code to require a connection from the meter main ground to the cold water pipe, within 5 feet of where it enters the house.

The shop doesn't have water, so I understand I need to connect it to the cold water pipe entrance to the house (at the front). The gas mater is there as well. So I thought I'd stick them in the same trench.

As for the size, I think 1/0 Cu is required for a 400A panel. Is there a section of the NEC you can point me to?

Thanks,
Bob

Ok so 1/0 cu is correct. GEC sizing is based on service conductor size. The art. # is T250.66 for the GEC. For service conductor sizing see T310.15(B)(7) (NEC 2011)

 

[bob_mp]

I just heard back from the city. They do allow ground conductors in the same trench without any additional spacing.

Thanks for the help and the pointer to the section of the code.

Bob

 

[Aceman]

Who told you that you need a seperate ground from the shop back to the home to hit the water pipe?

You are required to have a grounding electrode system at each building or structure, with a 4 wire feed between them. Running supplemental ground wires is not required.

For the gas, I'll will sometimes run a #4 to it from the panel OR if you only have one gas appliance sometimes it's easier to pigtail a ground wire out of the appliance and hit the gas line. Either way is acceptable.

 

[wyliesdiesels]

Most houses have the gas pipe bonded via the appliance being grounded through the EGC feeding the appliance receptacle.