NEC 2023 547.3

[ericm]

Hi, the builder and I are working on a permit for the new shop to go on my farm in Oregon.

They sent me a county document to be filled out and notarized. It has a few questions like will there be farm animals or hay in the building and will there be major mechanical work (i.e. removing engines). The answer to the first two is no but it's yes to the last one. If that box is checked they say the building will have to meet 547.3. That says:

for building not having conditions as specified in 547.1 (animals and hay), the electrical installation shall be made in accordance with applicable parts of this Code.

Ok fine, except nothing in the rest of 547 mentions anything about mechanical work. What am I missing? Yes I'm just going to tell the electrician to meet 547.3 but I want to know what it is. In case you're wondering the current plan is to have all the wiring in conduit on the walls. "Industrial standard" is what one electrician called it.

 

[mm08822]

Define major.

I wouldn't think backyard mech counts as major.

Private prop or commercial?

 

[ericm]

Define major.

the document defines major as
"engine overhauls, painting, body and fender work, and repairs requiring draining the vehicle fuel tank"

I wouldn't think backyard mech counts as major.

It's a farm. According to the ordinance you have the right to have a farm shop on your farm. It can't be open to the public and a bunch of other things I'm not going to repeat here and that I don't want to do anyhow. I'd need different permits for those. It's for working on farm equipment. They specifically allow the farmer and their family to work on whatever personal stuff they want. Like cars. Working on tractors and cars is what I want to do, so I'm set per the rules. I just want to know what the electrical requirements in NEC 547.3 mean so when I tell the electrician to do that, I know what I'm getting.

Private prop or commercial?

Private.

 

[35Ford]

547.3 doesn't say much of anything. I believe all it is saying is if the space not being used for things a barn is typically used for, it will need to be wired for the use of that space. Auto repair facility? Airplane Hanger? Operating room? Indoor Pool? Dry storage? You decide and wire accordingly.

 

[Chuckster in NJ]

547 is meant for farm animals so everything electrical can be washed down and is dust proof. ANIMAL Barns are dusty, dirty, corrosive, wet, vermin infested buildings and they need an equal potential grid installed.

The OP has a building for storage of farm related equipment and it should NOT fall under 547.

TIP! The less you tell the local authorities the better you will make out.

 

[PCustoms]

https://www.ecmag.com/magazine/articles/article-detail/agricultural-building-wiring-unlisted-appliances-and-more

 

[ericm]

https://www.ecmag.com/magazine/articles/article-detail/agricultural-building-wiring-unlisted-appliances-and-more

Thanks. So 547.3 just means I have to meet the rest of the NEC that I'd be meeting anyhow? That's kind of confusing.

 

[ericm]

TIP! The less you tell the local authorities the better you will make out.

My preference is to do things the right way so I don't have to worry about the inspector coming back for final and finding something wasn't done.