Path of GEC when bonding gas pipe

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augie47

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Tennessee
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State Electrical Inspector (Retired)
thanks Augie, that's exactly what I was asking. When you say "There are other ways to connect at the pipe that would allow you to hit it first." could you elaborate?

Thanks
Since you are just bonding the gas pipe, I think it would be compliant to run your GEC to the ground rod and tap off (splitbolt) to the gas pipe.
To some degree the entire scenario may be mute if it's standard gas piping as 250.104(B) allows the piping to be bonded by the equipment grounding conductor connected to the equipment served.
As Dennis mentioned, CSST piping is an entirely different animal.
 

Gregg Harris

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Virginia
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Electrical,HVAC, Technical Trainer
thanks Augie, that's exactly what I was asking. When you say "There are other ways to connect at the pipe that would allow you to hit it first." could you elaborate?

Thanks
I do not see where it makes any difference which one you attach to first short of creating a weak link. The gas pipe can be terminated on 4 different location.

Now if the gas pipe has CSST and the service is 200 amps or larger then the bonding jumper would need to be a # 4 copper and that could not land on the ground rod that has the # 6.


(B) Other Metal Piping. If installed in, or attached to, a building or structure, a metal piping system(s), including gas piping, that is likely to become energized shall be bonded to the service equipment enclosure; the grounded conductor at the service; the grounding electrode conductor, if of sufficient size; or to one or more grounding electrodes used. The bonding conductor(s) or jumper(s) shall be sized in accordance with 250.122, using the rating of the circuit that is likely to energize the piping system(s). The equipment grounding conductor for the circuit that is likely to energize the piping shall be permitted to serve as the bonding means. The points of attachment of the bonding jumper(s) shall be accessible.
 

George Stolz

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Windsor, CO NEC: 2017
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250.52(B) would prohibit the gas pipe from being between the rod and the panel, along with 250.64.

As drawn, there is no problem with the installation. In fact, this will be expressly permitted in 2014 (barring further changes.)
 

Dennis Alwon

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Chapel Hill, NC
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250.52(B) would prohibit the gas pipe from being between the rod and the panel, along with 250.64.

As drawn, there is no problem with the installation. In fact, this will be expressly permitted in 2014 (barring further changes.)

I don't see it. If the grounding electrode conductor is a continuous run from the panel to the gas pipe and to the rod what difference does that make. The gas pipe is not an electrode- assuming you connect on the load side
 

Gregg Harris

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Location
Virginia
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Electrical,HVAC, Technical Trainer
The gas code only requires a #6 to CSST piping.

The gas code uses the exact verbiage as the CSST manufacturers
"The bonding jumper shall not be smaller than # 6 copper or equivelant"
design listings state the bonding jumper should be sized per NEC 250.66 for the standard CSST. The new design of the CSST with the black carbon compost covering states to size it to 250.122 as you would do for bonding under 250.104 (B).
 

Gregg Harris

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Virginia
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Electrical,HVAC, Technical Trainer
I don't see it. If the grounding electrode conductor is a continuous run from the panel to the gas pipe and to the rod what difference does that make. The gas pipe is not an electrode- assuming you connect on the load side

I would agree, it would not be considered an electrode untill it enters the ground, and by being isolated from the section that is in the ground by the dielectric gas cock any atachment down stream of the isolation would be bonding.
 

mwm1752

Senior Member
Location
Aspen, Colo
250.104B states the EGC for the circuit likely to energize the piping shall be permitted to serve as the bonding means, Seems to relate to the gas boiler/fireplace being fed by a branch circuit. There should be no way the gas piping should be part of the electrode system.
 

mwm1752

Senior Member
Location
Aspen, Colo
Bonding CSST is per manufacture installation instructions. Only if it is part of the gas branch line. A appliance attachment does not trigger the bonding.
 

Gregg Harris

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Location
Virginia
Occupation
Electrical,HVAC, Technical Trainer
Bonding CSST is per manufacture installation instructions. Only if it is part of the gas branch line. A appliance attachment does not trigger the bonding.
"

Except for the new CSST that has a black carbon composite covering states " no further bonding requirement required by the manufacturer" but is still required to be bonded according to the fuel gas codes. From the latest IOM "The bonding requirements for the new product is to be in accordance with NFPA 70 Article 250.104 in the same manor as the minimum requirements for rigid metal pipe".

They are strugling to meet any type of consistancy that can be followed. It will be amazing if there third party testing will satisfy NFPA to allow it to be continued in use or dropped from being an approved system.
 

Dennis Alwon

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Location
Chapel Hill, NC
Occupation
Retired Electrical Contractor
The gas code uses the exact verbiage as the CSST manufacturers
"The bonding jumper shall not be smaller than # 6 copper or equivelant"
design listings state the bonding jumper should be sized per NEC 250.66 for the standard CSST. The new design of the CSST with the black carbon compost covering states to size it to 250.122 as you would do for bonding under 250.104 (B).

Not all csst manufacturers state to use T. 250.66-- I asked our state inspector and he said no matter what the service size only a #6 is required-- well I use T. 250.66 to cover my butt as it seems no one seems to know what they are doing with the CSST.

Black iron is easy-- the equipment grounding conductor is all that is needed as stated earlier.
 
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