Open-air horse barn.

[wirebender]

Is an open-air barn with stalls for horses covered under 547.1?

I can't see where excessive dust accumulation or corrosive atmosphere would be present.Construction is of steel poles and rails with wood up to about 4 feet, open from there on up to a metal roof. Dirt floors, no concrete anywhere.

If it is covered, does anyone have some experience with this type installation? Any tips? What about the equipotential plane, or would this not be considered an "outdoor confinement area"?

Service conductors (EC installed) will come from a utility pad mount. Service equipment is located on the outside of the barn. I will use the metal frame as the grounding electrode. Water supply is plastic. The only electrical is water troughs with auto-fill and heat, receptacles for fans at 10 feet above grade and some fruit jar lights. I am installing everything on GFCI breakers and pulling equipment ground with all circuits.

Thanks for the help.

 

[gndrod]

Is an open-air barn with stalls for horses covered under 547.1?
The only electrical is water troughs with auto-fill and heat, receptacles for fans at 10 feet above grade and some fruit jar lights. I am installing everything on GFCI breakers and pulling equipment ground with all circuits.

Thanks for the help.

Looks like the only thing 547 does not mention, is wirng protection above cribbing heights.

 

[ptonsparky]

At minimum I would consider it a damp location. UF cable. Horses will chew on anything so keep it high.

The more I think about how expensive hay burners can be, the added cost of 547.1 might be a good CYA insurance. Not that much difference now that 08 NEC is just around the corner.

 

[JohnJ0906]

Tony, maybe you should check with the AHJ in your area to see what their requirements are.

 

[George Stolz]

Is an open-air barn with stalls for horses covered under 547.1?

It could be, you'd need to check with the AHJ, IMO.

I can't see where excessive dust accumulation or corrosive atmosphere would be present.

I've got four horses in an open barn, they get fed outside. It's still got a lot of combustible dust out there.

Dirt floors, no concrete anywhere.

(snip) What about the equipotential plane, or would this not be considered an "outdoor confinement area"?

If there's no concrete, there's no requirement for an equipotential plane. See the definition of equipotential plane in 547.2.

I will use the metal frame as the grounding electrode.

Under which provision of 250.52(A)(2)?

I am installing everything on GFCI breakers and pulling equipment ground with all circuits.

Sounds like a good idea, and I would also seperate lighting and receptacle loads. I'd also consider running all Schedule 80 PVC as the primary wiring method, IMO, but would be curious what others think about that.

Looks like the only thing 547 does not mention, is wirng protection above cribbing heights.

547.5(E) requires protection where required, which I think would cover about everything accessible in a horse barn under 10 feet. Just curious, what damage do you see above cribbing heights?

 

[wirebender]

It could be, you'd need to check with the AHJ, IMO.

This is in a rural area in Texas. Does anyone know who would be considered the AHJ? I don't know if the state is even set up to address these issues.

If there's no concrete, there's no requirement for an equipotential plane. See the definition of equipotential plane in 547.2.

Maybe I'm misreading 537.10(A).

(A) Where Required Equipotential planes shall be installed in all concrete floor confinement areas in livestock buildings, and in all outdoor confinement areas such as feedlots, containing metallic equipment that may become energized and is accessible to livestock.

The pad mount and the service equipment are outside the building and are accessible to livestock. The summary of changes makes it clear that equipotential planes are to be installed in "outdoor confinement areas consisting of either concrete or dirt surfaces". What constitutes an "outdoor confinement area? The whole ranch is an "outdoor confinement area".

Quote:
I will use the metal frame as the grounding electrode.

Under which provision of 250.52(A)(2)?

IMO (of course that is not NEC opinion, I'm sure ) 28 6" steels poles buried in the ground and welded together with rails would be effectively grounded. I don't know if this would be considered a "single structural member in direct contact with the earth" by NEC.

Sounds like a good idea, and I would also seperate lighting and receptacle loads. I'd also consider running all Schedule 80 PVC as the primary wiring method, IMO, but would be curious what others think about that.

Yes, lighting on separate circuits. Fan and water trough for every two stalls on each circuit. EMT is the primary wiring method. I should point out that I am doing this for another EC who couldn't get to it and this is his design. I am really just checking with you guys to make sure about liability issues, his and mine. I know I don't want to pay for a dead steeplechaser.

 

[George Stolz]

Maybe I'm misreading 537.10(A).

The summary of changes makes it clear that equipotential planes are to be installed in "outdoor confinement areas consisting of either concrete or dirt surfaces".

A summary of changes is not the NEC. By definition, an equipotential plane consists of a metallic grid with concrete either covering or encapsulating it. I read 547.10(A) as well, but we can't ignore the definition. IMO, 547.10(A) still works if you take the concrete for granted, because it's saying it's required both inside and outside, where metallic electrical equipment is present.

Whether the intent was to cover dirt outdoor lots or not, the definition doesn't support that enforcement, IMO.

What constitutes an "outdoor confinement area? The whole ranch is an "outdoor confinement area".

If the whole ranch is fenced in, then I guess all outdoor metallic electrical equipment with concrete near it will have to have that concrete e-bonded to the metallic equipment.

IMO (of course that is not NEC opinion, I'm sure ) 28 6" steels poles buried in the ground and welded together with rails would be effectively grounded. I don't know if this would be considered a "single structural member in direct contact with the earth" by NEC.

I imagine, I was just double-checking that you'd reviewed the criteria before you settled in on it.

I'd say EMT is a good choice too.

 

[gndrod]

Above Crib heights

Above Crib heights

547.5(E) requires protection where required, which I think would cover about everything accessible in a horse barn under 10 feet. Just curious, what damage do you see above cribbing heights?

HI George,

Might not be common, but would you believe, overhead worn electrical used to support rope-hoisted feed buckets. rbj

 

[cschmid]

lol hay burner heaven..Horse will chew and dig when confined to stalls..anything then can bite should be ridged and nothing under the floors of the stalls..horse are not like milk cows or a feed lot for cattle where growth and milk production are the primary bussiness..I like the ground grid idea I think that is good..just remember horses are destructive when confined..so make sure you don't leave your self to own a over priced hay burner..

 

[George Stolz]

...so make sure you don't leave your self to own a over priced hay burner..

Confined or not, truer words never spoken.

Critters can be fun, but the bigger they get, the bigger the bills.

Might not be common, but would you believe, overhead worn electrical used to support rope-hoisted feed buckets.

I hadn't thought of that, good point.