Eq. ground as the bonding conductor

[txkmarty]

Hello all, I've used the forum for a long time and it's been very helpful, now I've got a question of my own. I've looked several times and for the life of me can't find this in the code, maybe I dreamed it. Is there a code section that explicitly states that the equipment grounding conductor can serve as the bonding conductor? Have a spec that is calling for a separate "bonding" conductor in addition to the green wire, installed outside the conduit.

 

[LarryFine]

Welcome to the forum.

A single conductor can serve more than one purpose if it's sized and installed to meet all requirements.

 

[txkmarty]

Thanks for the quick reply Larry, do you know a code section off hand? I know it's allowed but would like to have the ability to show chapter and verse if the question comes up

 

[electrofelon]

Hello all, I've used the forum for a long time and it's been very helpful, now I've got a question of my own. I've looked several times and for the life of me can't find this in the code, maybe I dreamed it. Is there a code section that explicitly states that the equipment grounding conductor can serve as the bonding conductor? Have a spec that is calling for a separate "bonding" conductor in addition to the green wire, installed outside the conduit.

I think the way it works is THEY would have to point to a code that requires the additional jumper!

 

[ramsy]

THEY would have to point to a code

Under engineering supervision architectural specifications, and plans typically deviate from NFPA idiot tables, in-favor of other verified and validated standards, such as IEC, IEEE, or expert systems like ETAP.

When specs conflicts with code, contractors may submit an RFI, or suggest their preferred code alternative.

If Op shows us the spec, code alternatives are more likely.

 

[LarryFine]

Thanks for the quick reply Larry, do you know a code section off hand? I know it's allowed but would like to have the ability to show chapter and verse if the question comes up

No, but the NEC is generally viewed as a permissive code, effectively specifying that which is prohibited.

 

[txkmarty]

This is the spec verbiage that I glossed over.
"In addition to the green colored equipment grounding conductor required in
each raceway and sized in accordance with Table 250.122 of NFPA 70, bond
each panelboard, switchboard enclosure, transformer housing, motor
housing, disconnect, starter, and other electrical equipment, to the
grounding system with a stranded copper conductor, routed external to the
feeder raceway."
(Corp of Engineers Spec) Been working of COE projects 30+yrs, never saw this one before. My main concern here is what they are going to define as "other electrical equipment" as we all know a bond jumper can't be outside conduit for more than 6' (250.102.D.2) in which case I'm installing a separate conduit for bond conductors. Hopefully I can convence them fixtures, switches and receptacles aren't "equipment" Panels and transformers would be manageable

 

[txkmarty]

Ok JUST Found what I knew I'd seen before. Informational note on Article 100 Definitions Grounding Conductor, Equipment Note 1 "It is recognized that the equipment grounding conductor also perfoms bonding"

 

[electroman00]

Is there a code section that explicitly states that the equipment grounding conductor can serve as the bonding conductor?

Yes/No...However it is easy to conflate Grounding/Grounded conductors and bonding...

Have a spec that is calling for a separate "bonding" conductor in addition to the green wire,

That's very vague!

I suspect this is a Transformer installation?

installed outside the conduit.

Code violation...
if it is jacketed wire...
and design caution for parallel grounding !!

Electrical bonding is the practice of intentionally electrically connecting all exposed metal items not designed to carry electricity in a room or building as protection from electric shock. Bonding is also used to minimize electrical arcing between metal surfaces with electrical potential differences.

The equipment grounding conductor shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded. The equipment grounding conductor shall be sized in accordance with 250.122

You have Homework...

 

[ramsy]

"In addition to the green colored equipment grounding conductor required in
each raceway and sized in accordance with Table 250.122 of NFPA 70, bond
each panelboard, switchboard enclosure, transformer housing, motor
housing, disconnect, starter, and other electrical equipment, to the
grounding system with a stranded copper conductor, routed external to the
feeder raceway."

Separately bonding swimming pool equipment like that, with solid #8cu, is SOP for bonding grids in Article 680.26

"bonding jumper" at NFPA link brings up 250.53(C) electrodes, parallel raceways, & supply side SDS, among others.

 

[electroman00]

"In addition to the green colored equipment grounding conductor required in
each raceway and sized in accordance with Table 250.122 of NFPA 70, bond
each panelboard, switchboard enclosure, transformer housing, motor
housing, disconnect, starter, and other electrical equipment, to the
grounding system with a stranded copper conductor, routed external to the
feeder raceway."

That's the definition of parallel grounding !!

 

[electrofelon]

That's the definition of parallel grounding !!

Are you saying *parallel grounding" is a code violation? Maybe, I admit I'll have to think about it before making a stance. Does installing an additional EGC make it necessarily fall into a parallel installation this having to comply with 310.10(H), or can I say it is just an additional not code required conductor so thus I can do whatever i want?

 

[Jpflex]

Hello all, I've used the forum for a long time and it's been very helpful, now I've got a question of my own. I've looked several times and for the life of me can't find this in the code, maybe I dreamed it. Is there a code section that explicitly states that the equipment grounding conductor can serve as the bonding conductor? Have a spec that is calling for a separate "bonding" conductor in addition to the green wire, installed outside the conduit.

The green wire outside conduit is usually for flexible metal conduit not over 6 feet.

Equ

 

[don_resqcapt19]

Hello all, I've used the forum for a long time and it's been very helpful, now I've got a question of my own. I've looked several times and for the life of me can't find this in the code, maybe I dreamed it. Is there a code section that explicitly states that the equipment grounding conductor can serve as the bonding conductor? Have a spec that is calling for a separate "bonding" conductor in addition to the green wire, installed outside the conduit.

All of my industrial jobs have required an external bonding jumper around the LFMC connections to motors, even though there is an EGC in the raceway. The code would be fine with just the internal EGC.
This is a design issue. If the specs call for the external bonding jumper you have to take that up with the design engineer.