House, barn, and outbuilding fed with 3 wire

[kwired]

It is a "site isolating device" and allowed by 547.9(A). 4 wire would be required from the pole top switch to the buildings by 547.9(B)(3)

547.9(B)(3) says the grounding and bonding has to comply with 250.32 and 250.32(B)(1) requires an equipment grounding conductor to be installed to separate buildings.

EGC only required to buildings covered by 547, not a 547 building but on same site as a 547 building - it is simply supplied by service conductors - art 230 applies. If the 547 building is the only building/structure supplied the site isolating device is not required -547.9(A)(1).

Livestock operations have evolved to the point that you essentially have a small industrial plant these days - some supplied by 480/277 800 - 2000 amp services. Big difference from what was common back when 547 was first introduced into NEC, yet a lot of 547 hasn't really changed much over the years.

Not quite sure what the reasoning here is, but I’ve yet to be required 4 wire at any rural distribution where an unfused disconnect or terminal box is located at the meter pole, or anywhere else. New houses are required to be inspected but are connected to the existing distribution. Three wire.

For the most part, farm buildings in this area no longer would be considered Agricultural Buildings but are still exempt from inspection. I have never seen a pole top disconnect.

Randy Anderson (when he was still the local inspector up this way) once told me they don't consider the disconnect on the pole(provided by POCO) as the service disconnecting means even if it has overcurrent protection. I can understand the reasoning, here the POCO installs those - but they are customer's equipment because they did pay for them. But should they decide to have POCO install one of those double throw switches they do provide - those don't have overcurrent protection and my replace something that you were calling service disconnect, as well as some other situations seem to pop up once in a while that is similarly confusing on service disconnecting means. Now that was nearly 20 years ago - but seems they still look at it in the same way here, though I haven't had any recent conversation on it with any inspectors.

What I had going on at the time Randy told me that was I wanted to connect a mobile home - it was on a rural service which did have overcurrent protection on the pole disconnect. I still had to install an additional service disconnect for that mobile home in that case as they didn't consider the one on the pole to be a service disconnecting means.

 

[ptonsparky]

Very few Mom&Pop farms any more and with the State AG stating that rented Ag properties are no longer exempt from inspection things may change, maybe, someday. They don’t have enough manpower to add those inspections. CYA ruling at best.

 

[kwired]

Very few Mom&Pop farms any more and with the State AG stating that rented Ag properties are no longer exempt from inspection things may change, maybe, someday. They don’t have enough manpower to add those inspections. CYA ruling at best.

I was not aware of rented property thing - but at same time how do they know? Even in rented property I usually work for the owner not the renter. Sometimes don't even know who the renter is. Inspectors are not going to take the time to research all that, they have enough to do as is.

 

[MAC702]

...Even in rented property I usually work for the owner not the renter...

If for the renter, it is still with the owner's consent, right?

Both the owner and myself got pretty pissed at a renter once for hiring me without telling me they didn't own the place.

 

[ptonsparky]

If for the renter, it is still with the owner's consent, right?

Both the owner and myself got pretty pissed at a renter once for hiring me without telling me they didn't own the place.

Some is, some not. Depends on what needs done and how they have things worked out between them.

 

[kwired]

If for the renter, it is still with the owner's consent, right?

Both the owner and myself got pretty pissed at a renter once for hiring me without telling me they didn't own the place.

We are talking about rented farm ground here, sometimes I am coming to site for service call on renter's portable equipment - that is usually between me and renter, but to work on permanent wiring that is essentially part of the real estate is usually between me and the owner.


But there are times when owner and renter can't agree on who is responsible for what - but if renter want to keep his grain in the owners bin from spoiling, he is usually willing to pay for repairs to aeration equipment if he has to, or other similar situations.

I have one larger family farm operation that I do a lot of work for - they own a lot of the ground they farm but also do rent some at times.
When they call me on those rented properties they usually pay me - mostly just service work and not new installs - and they deal with owner if they want reimbursed.

 

[maven]

Well, I spoke with an engineer from the POCO today. He suggested removing the pole top service and just installing a 200amp meter/breaker disconnect combo right on the pole and take 100 amps to the house and 100amps to the barns.

He said it is virtually unheard of to run 4 wire over head to feed a structure. He has never seen it done. So...I plan on just using the 3wire feeder that is there right now if it is big enough to handle 100amps. Hopefully it is at least #2 AL. I will check tomorrow.

So from my research it seems that 3 wire is ran to structures as long as the exceptions are met in 250.32(B)(1) Exception #1:

1) An equipment grounding conductor is not run with the supply to the building or structure
2) There are no continuous metallic paths bonded to the grounding system in each building or structure involved
3) Ground-fault protection of equipment has not been installed on the supply side of the feeder(s).

Am I on the right track?

 

[packersparky]

EGC only required to buildings covered by 547, not a 547 building but on same site as a 547 building - it is simply supplied by service conductors - art 230 applies. If the 547 building is the only building/structure supplied the site isolating device is not required -547.9(A)(1).

Livestock operations have evolved to the point that you essentially have a small industrial plant these days - some supplied by 480/277 800 - 2000 amp services. Big difference from what was common back when 547 was first introduced into NEC, yet a lot of 547 hasn't really changed much over the years.

I never said a site isolating device was required. I have been on farms recently that milked a maximum of 8 cows. That is not the norm anymore, but small milking farms are still out there.

 

[kwired]

I never said a site isolating device was required. I have been on farms recently that milked a maximum of 8 cows. That is not the norm anymore, but small milking farms are still out there.

If you are in it to profit, 8 cows don't cover overhead expenses unless you have some special market for what you are producing. You are not producing enough milk for the mainstream milk buyers to even be interested in buying from you.

If you are selling directly to consumers you maybe can make some money, but probably not a lot off the production of just 8 cows.

Are those you see with 8 cows hand milking or are they using automated equipment?

Probably not worth cost of becoming grade A certified - which is sort of like electricians not getting a license.

 

[ptonsparky]

...which is sort of like electricians not getting a license.

OT. Each time I have to renew insurance for a year to hold that license, I am tempted to drop both.

 

[kwired]

OT. Each time I have to renew insurance for a year to hold that license, I am tempted to drop both.

I am tempted to drop everything on a nearly daily basis anymore, but not sure what I would do as everything is regulated to death anymore, might as well stick with what I know the most about.

 

[ActionDave]

Well, I spoke with an engineer from the POCO today. He suggested removing the pole top service and just installing a 200amp meter/breaker disconnect combo right on the pole and take 100 amps to the house and 100amps to the barns.

He said it is virtually unheard of to run 4 wire over head to feed a structure. He has never seen it done. So...I plan on just using the 3wire feeder that is there right now if it is big enough to handle 100amps. Hopefully it is at least #2 AL. I will check tomorrow.

So from my research it seems that 3 wire is ran to structures as long as the exceptions are met in 250.32(B)(1) Exception #1:

1) An equipment grounding conductor is not run with the supply to the building or structure
2) There are no continuous metallic paths bonded to the grounding system in each building or structure involved
3) Ground-fault protection of equipment has not been installed on the supply side of the feeder(s).

Am I on the right track?

Yes, you are on the right track.

 

[junkhound]

If there is no OCPD associated with the pole top disconnect, then it cannot be a "service disconnect" under the NEC. You have three sets of three wire service conductors, which is perfectly fine. Each building needs a disconnect (breaker panel or fused disconnect) that is listed for use as service equipment and each building needs its own Ground Electrode System. These GESs will not interconnect.

+1.

Have an ADU at son's house, both fed from same xfmr, poco installed 3 wire to each. 200 A service at each building.

Common water supply and sewer, but PEX and PVC piping. No internet cable directly between buildings either, service cable routed from common Comcast box on the street. CCE ground at ADU, regular rods at main building.