Gec Conductor
- Thread starter wmeek
- Start date
- Status
MasterTheNEC
CEO and President of Electrical Code Academy, Inc.
- Location
- McKinney, Texas
- Occupation
- CEO
In my opinion, if you read 250.104(C) very close you will see that this in my opinion is not "structural steel" that forms the building frame, it is a steel component and unless something is different than normal I would also say it is not likely to become energized and so on. Obviously, each condition is different and the likely hood can change from job to job (this is the AHJ's call) but thats my view on it.
For those that say it has to be bonded....so you are going to install a bonding jumper from Steel Bar Joist to Steel Bar Joist....in this SPECIFIC example...I think not.
Just my opinion...for what that is worth...about 2 cents !
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
The structural steel in 250.104(C) is not necessarily the same thing as the metal mentioned in 250.52(A)(2) that is a qualifying grounding electrode.
The steel in 250.104(C) only needs bonded when in a situation where it is likely to become energized. That determination may mostly depend on opinions.
The metal mentioned in 250.52(A)(2) if it meets the requirements for an electrode as stated in that section must be used as an electrode - and will inherently bond any other structural metal it is connected to.
The steel in 250.104(C) only needs bonded when in a situation where it is likely to become energized. That determination may mostly depend on opinions.
The metal mentioned in 250.52(A)(2) if it meets the requirements for an electrode as stated in that section must be used as an electrode - and will inherently bond any other structural metal it is connected to.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I know that some inspectors require metal studs to be bonded but that can be done with the equipment grounding conductor not grounding electrode conductor. Normally the 4" sq. boxes mounted to the studs will suffice but I have heard other say the inspector wanted every stud bonded---:happysad:
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Do you know what code section they may be citing on the metal studs? I certainly hope not 250.104(C) as I don't see that applying to most typical instances with metal studs. First disqualifier - they generally are not exposed.
- Location
- Massachusetts
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
It is a Florida rule. This is from another thread about it.
Originally Posted by bphgravity
This requirement was added to the Florida Building Code after an appliance installer was electrocuted while he was attempting to connect the dryer exhuast duct on a new single-family dwelling. It appears the the kitchen cabinet installers drilled a screw through the range cord and into a metal stud. This energized the metal framing which was also in contact with the dryer exhaust duct. There was no effective fault path once the metal stud became energized.
The section is written poorly and does not follow NEC language or the NFOA style manual. Most installers simply use one or more metal boxes for branch circuit outlets when installed in a metal stud wall / ceiling. After the intitial learning curve and confusion on how to comply, it really has not been a major compliance issue...
Though it is sad that a person got electrocuted, my question to those that made this rule is why stop with metal studs? Same thing could happen with sheet metal siding, roofing, metal cladding on doors, windows, other similar items, HVAC ducting, the list could be endless of what may need bonded.
I have seen people hit concealed cables when drilling or sawing into a wall and get nailed by the voltage in those cables.
In the case of the cabinet screw and the metal stud - either the conductor was too close to edge of stud, or cabinet installer was using more screw then really necessary. Maybe we could require the use of RMC as the wiring method and it would help quite a bit with the risk of driving screws into the wiring. From someone that makes more money when the job takes more time and/or materials - I could go for that rule
- Location
- Massachusetts
I agree with your thoughts.
The reason I remembered it at all was because when I leaned of the rule it stood out in my mind as foolish code making.
Right near me now is a large roll around tool box with a live extension cord running by it. It is possible that the cord gets yanked around the edge of the box, the insulation gets skinned exposes the hot copper and energizes the box.
Should we run a bond wire to it? :huh:
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Apparently there is at least one place in Florida where you probably have to. Better run bonding jumpers from the tool box to all metallic tools it contains while you are at it.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
And if the bonding jumpers are in the form of chain or aircraft cable, you might deter theft at the same time!
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Chain isn't generally deemed a good bonding conductor:happyno:And if the bonding jumpers are in the form of chain or aircraft cable, you might deter theft at the same time!
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
People think it works for grounding cars and trucks. :angel:
- Location
- Illinois
- Occupation
- retired electrician
When I started it was a common practice to wrap chain around switch gear bus after opening the breaker, before working in the gear.
- Status