Another question about Main Bonding Jumper

[wwhitney]

Although I think the sections are pretty explicit that you can do the things that cause the supposedly objectionable current which evidently isn't objectionable because you can do those things.

Seems to me that 250.6 is saying "even if other sections say you may do X, if it results in objectionable current, you must remediate it in one of the following ways."

2) In SF, where I got started, only hard metallic conduit is permitted for service conductors so there's really no way around it.

Apparently that is out of date? If up.codes is to be believed, the 2022 SF electrical code says that service entrance conductors shall be limited to the following wiring methods: RMC, IMC, Busways, Auxilliary gutters, PVC, MI, HDPE, NUCC, and RTRC.

Chapter 2 Wiring and Protection: San Francisco Electrical Code 2022 | UpCodes

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up.codes

Cheers, Wayne

 

[don_resqcapt19]

Yes it would certainly help if they defined it. My theory (again, just going by what the words say and letting go of common practice) is that neutral current flowing on service raceways must be objectionable . I say this because: 1) the degree to which the NEC tries to eliminate current flowing on things other than intended conductors. 2) SDS's already have language prohibiting parallel paths. 3) I can't think of what else it could mean. Can you think of an otherwise code compliant installation that "objectionable current" could be referring to?




That is a new section I was not aware of. I am torn between that being an improvement that can live in harmony with "rearranging or interrupting", and it being completely contradictory.

Since the code does not define it, it can be anything I want it to be making 250.6 unenforceable. One other would be using the EGC as a current carrying path, something that was not specifically prohibited until a couple of code cycles ago.
However without an definition, I really have no idea what the term means when trying to enforce the NEC.

 

[electrofelon]

Since the code does not define it, it can be anything I want it to be making 250.6 unenforceable. One other would be using the EGC as a current carrying path, something that was not specifically prohibited until a couple of code cycles ago.
However without an definition, I really have no idea what the term means when trying to enforce the NEC.

That is certainly one philosophy. However, do you consistently apply that across the NEC? They do not define "subject to physical damage" , so does that mean you would not enforce any code violations related to potential for damage to raceways and cables?

BTW I believe that section is dumb and should be deleted. However as long as it's in there, if I were an inspector it would be my duty to interpret it and enforce it.

 

[don_resqcapt19]

That is certainly one philosophy. However, do you consistently apply that across the NEC? They do not define "subject to physical damage" , so does that mean you would not enforce any code violations related to potential for damage to raceways and cables?

BTW I believe that section is dumb and should be deleted. However as long as it's in there, if I were an inspector it would be my duty to interpret it and enforce it.

I simply define subject to physical damage based on the conditions of the install. Both NM and MC cable have the same prohibition on installing those cables where "subject to physical damage" but I will approve MC in areas I would approve NM,

There are cases where I might find a parallel path objectionable, but never related to service raceways.