Equipotential bonding

[Joe Keul]

I have a contractor that is going to be wiring the new building (black outline) that is fed from a separate transformer and service. The serving utility is requiring that the service in the existing building be completely isolated from the new building. They requiring that the metal roof be broken up by a piece of acrylic roofing material, and that the concrete between the existing building and the new building creates a "neutral" plane, so that piece of concrete will have no metal in it, and a voltage gradient will be placed at the end of each slab of the two buildings. I understand the equipotential bonding of one building, however not sure if i agree with the serving utility in this particular instance. This is for a dairy farm in the state of Iowa. Keep in mind this is ag which is exempt from inspections, hence the 2 services, the utility is requiring the inspection of the bonding.

 

[Galt]

Is the new building another free stall or is it a new parlor?

 

[packersparky]

Does the area where the concrete is to be installed have metallic objects that can come in contact with the cows? If so, the EQ plane is required. Is this in Alliant Energy territory?

 

[Joe Keul]

The new building is new stall building. Serving utility is an REC. Yes the new building will have all bonding necessary for a livestock building. Just not sure what to think of the "neutral" plane between the two buildings. They will be attached but no metalic path between the two. Both buildings fed from same primary. I beleive there is a tap box for the primary conductors. Then there seperate transformers for each building.

 

[kwired]

The new building is new stall building. Serving utility is an REC. Yes the new building will have all bonding necessary for a livestock building. Just not sure what to think of the "neutral" plane between the two buildings. They will be attached but no metalic path between the two. Both buildings fed from same primary. I beleive there is a tap box for the primary conductors. Then there seperate transformers for each building.

I don't know how you can do that without effectively leaving one building while traversing across a gradient ramp and then enter the other building essentially the same way but reversing the gradient ramp.

To have a doorway that essentially goes directly between one building and the other leaves no room for a "neutral zone".

Thing is what is supply voltage, and are there SDS's in each building? The less line to neutral load you have on the service the less "stray voltage" problems you will experience.

 

[Joe Keul]

I believe the buildings will have enough room to put in voltage gradient ramps and have a "neutral plane" between them. Very minimal neutral load. Only 120 loaad are convenience receptacles. I believe everything else is 220 load, heaters for waterer, lighting, fans.