Horse stalls on residential property

[Rick 0920]

A customer has (3) horse stalls built on his property. When wiring the stalls, do the rules of agricultural buildings apply or is this still considered dwelling unit rules?

 

[kwired]

So the customer is Amish and you want advice on wiring his garage?

Read 547.1 carefully. I'd say this section applies to that area, and such an area could potentially be a part of about any occupancy type.

Temporary conditions wouldn't apply, like for a rodeo being held in a multipurpose arena. An arena at a county fair building that primarily has livestock shows as it's main function - maybe not the show arena itself applies so much but the area where these livestock are housed when not competing probably so.

 

[augie47]

I'm not saying that Art 547 doesn't apply but the situation you describe is commonplace throughout TN and I don't recall the full scope of Art 547 ever being required especially the equipotential bonding. TN State Code does address fixtures in hay row areas but nothing beyond that has been required that I know of.

 

[Rick 0920]

I'm not saying that Art 547 doesn't apply but the situation you describe is commonplace throughout TN and I don't recall the full scope of Art 547 ever being required especially the equipotential bonding. TN State Code does address fixtures in hay row areas but nothing beyond that has been required that I know of.

My customer has spared no expense on these horse stalls. I could live comfortably in there! LOL They are completely enclosed in what I would consider a dry location. Could NM-B be installed in the concealed walls only and the wiring methods described in 547.5 be used in any exposed work?

 

[acrwc10]

I don't believe electricity behave differently in residential locations vs commercial locations, that said I would be enforcing Art 547. Especially the equipotential grounding grid, I have read enough stories of cows milk production dropping and horses not drinking out of the water troughs where there was no equipotential grounding grid to know they are needed.

 

[infinity]

Article 547 applies to horse barns. I wrote a proposal a few years ago to have equine added to the list with chickens, etc. It was rejected because they said that the USDA classified horses as livestock. Seems pretty stupid for the CMP to not add one word to the article's scope to end the confusion but then CMP and stupid sometimes go together.

 

[kwired]

Article 547 applies to horse barns. I wrote a proposal a few years ago to have equine added to the list with chickens, etc. It was rejected because they said that the USDA classified horses as livestock. Seems pretty stupid for the CMP to not add one word to the article's scope to end the confusion but then CMP and stupid sometimes go together.

Chickens don't have long enough legs or distance between them for the same needs you get out of equipotential plane/equipotential bonding as is needed for larger four legged animals like cattle, horses, pigs, etc. Other items from 547 can still be similar like wet, damp, corrosive, mixed with feeds, bedding and other materials that can also add a dust component to the mix of things.

I will agree that some horse barns can almost fit into the cleanliness level or even higher than some homes that are occupied by some humans though.

If you have a concrete floor you pretty much need an equipotential plane to comply with NEC. I still seen many that don't have it and have little issues. Sort of comes down to some extent (reality wise) what you might have for electrical that comes fairly close to what the animals can come in contact with. Water tanks with electric heating elements are fairly common unless is an indoor location that never will get below freezing temperatures. Outside of dairy farms and maybe swine farrowing facilities (at least with types of places I have commonly encountered) often there is little else that is that close to the animals. Automatic feed systems usually have motors and such out of reach of animals (except for poultry but again they don't have same equipotential issues as large animals) and non conductive drop tubes and such.

 

[acrwc10]

Chickens don't have long enough legs or distance between them for the same needs you get out of equipotential plane/equipotential bonding as is needed for larger four legged animals like cattle, horses, pigs, etc. Other items from 547 can still be similar like wet, damp, corrosive, mixed with feeds, bedding and other materials that can also add a dust component to the mix of things.

I will agree that some horse barns can almost fit into the cleanliness level or even higher than some homes that are occupied by some humans though.

If you have a concrete floor you pretty much need an equipotential plane to comply with NEC. I still seen many that don't have it and have little issues. Sort of comes down to some extent (reality wise) what you might have for electrical that comes fairly close to what the animals can come in contact with. Water tanks with electric heating elements are fairly common unless is an indoor location that never will get below freezing temperatures. Outside of dairy farms and maybe swine farrowing facilities (at least with types of places I have commonly encountered) often there is little else that is that close to the animals. Automatic feed systems usually have motors and such out of reach of animals (except for poultry but again they don't have same equipotential issues as large animals) and non conductive drop tubes and such.

So the, "chickens don't have long enough legs" comment was as informative as it was funny. The issue of "neutral earth voltage" is why an equipotential grid is needed. If the transformers and power poles are in good shape or too far away, there will be no problems.

 

[kwired]

The issue of "neutral earth voltage" is why an equipotential grid is needed.

I understand that. But why is it only needed in 547 applications and 680 applications and almost no where else?

I can walk up to a livestock water tank with say 10 volts from the tank to earth, may or may not get shocked when I touch it But I don't span over as much of a voltage gradient at the surface as a cow does plus my shoes likely provide at least some amount of insulation.

Cattle will feel that voltage as they approach. It gradually gets higher as they approach, plus they stand with one of their rear feet being maybe 4 or 5 feet, maybe even up to 6 feet further away than their closest front foot as they approach. They maybe only subject to 2 or 3 volts before the get all the way up to the tank, don't like it and just stay away from it.

Other animals like pigs, they just are found dead right next to the tank. Their curiosity gets them. If you ever been around open range pigs with electric fence to contain them, they keep coming back every so often to test it and see if it still zaps them. Cattle on the other hand get hit once and usually just stay away afterwards.

Poultry doesn't span across enough of a gradient to be an issue, other than maybe if you have a failed EGC and an object has full line to ground voltage on it. But that is still a problem even if you have equipotential plane at building approaches.

Also note the requirements aren't the same as they are in 680 which requires pretty extensive bonding, it is mostly required to only bond things that are likely to become energized as well as install equipotential planes at approach/exits and similar places.