The farm house is grounding is kinda different. I was set up in the 50s and now I’m changing it and none of it is clear as to how it relates to the NEC.
First off there’s a disconnect on a pole with the meter base. I see the co-op has a piece of number 6 going into the ground over there. Frome that pole there’s two three wire aerial drops.
Each of these aerial drops has another piece of number 6 tieing the neutral to a ground rod where the wires meet the house and the garage. Those three wires systems both run to panels in the house and the garage.
I’m changing out the panel in the garage. The drawing I got from the co-op now shows the ground rod #6 running to the panel. This is not a problem for me.
In the house, there’s a 3/4″ copper water pipe that runs to the spring. It’s at least fifty foot long. It runs underground and and hits the water. There’s always been water ( 50 gpm ) for the last 80 years.
At some point I replaced the 12/2 without ground from the pump to the panel with a 12/2 with ground and tied the equipment grounding conductor to the pump housing and to the water pipe. Now I believe I have two grounding electrodes tied by a number 12 running through the house.
The farm is ground zero for lightning strikes. Three surge protectors on the phone have been lost in the last year. Motion sensor lights on the front of the house just won’t last. Electronic ballasts in flourescent lights don’t last either.
I have a square-d secondary surge supressor on the house panel. Wired as the square-d drawing called for. I have no idea if it’s still any good.
There’s a 10/2 with ground running to the water heater right next to the copper water pipe running to the spring. Would you tie that equipment grounding conductor to the water pipe? Would you disconnect the pump equipment grounding connector from the water pipe as it might be a little small for the job I’m asking it to do?
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Hopefully 4lorn1 and CAP will give some better details.
The metalic water pipe is suppose to be bonded within 5ft of where it enters the house and if it extends at least 10 ft underground then it can also serve as one of the grounding electrodes. If it is used as a grounding electrode then you also need a second one.
And a ground rod also needs a second electrode unless it is tested.
So the common practice is driven ground rod and metal water pipe also connected with #6.
"At some point I replaced the 12/2 without ground from the pump to the panel with a 12/2 with ground and tied the equipment grounding conductor to the pump housing and to the water pipe. Now I believe I have two grounding electrodes tied by a number 12 running through the house."
"Grounds" are used for several purposes. One of which for fault currents from a branch circuit. Thus a #12 ground is appropirate to that pump circuit. And the motor should be connected to that EGC. There is no need to tie into the pipe at that point. But the pipe is probably also grounded at that end via the connections to the pump motor.
But that run of #12 can't carry surge currents from EMP's.
How many drops do you have with there own pannels (vs being a sub-pannel off the main)?
And what kind of animals do you have? I have heard that milk cows, in particular, are very sensitive to small voltage differences and there are special efforts to elimate them by proper grounding and bonding. But I don't know the details.
But the pipe is probably also grounded at that end via the connections to the pump motor.
Nope, it was not connected to the water pipe until I did it. The pump/motor is isolated from metal pipes through rubber hoses.
If I tie both the 12 and the 10 to the water pipe that's like a 20A and a 30A conductor. So it's electrically very similar to a #6. I understand the fault function of the EGC. It's transient surges on the line and EMPs from lightning I want to clamp.
Someday I plan to put a subpanel in the basement near this water pipe. It's under the kitchen. There's a whole bunch a branch circuits in this vicinity. The country boy electricians that wired this place in the 50s put the panel in the front of the house and ran a whole bunch of circuits to the back of the house where the kitchen is. When I put in that sub-panel, I'll have a nice fat piece of copper between the two electrodes. But Rome wasn't wired in a day.
Currently, I have no sub-panels. In both of my panels the nuetral and the EGC are tied. They are tied the way they used to do it. Where the service drop joins with the wires going to the panel they put the #6 under the split bolt. I am about to put the new panel in the garage and the #6 will go in under one of those set screws at that point.
I have all my eq to rework the garage panel 100A 20-20 General Electric, copper bus. Lowes had nice price on it including 5 - 20A breakers - $57. I am held up on nerve in cutting through the corrugated metal roof. But I am closing on that.
Big Macs 99 cents is a sales pitch. My cows are all end up in the food chain. When they get hit with stray voltage it's 2 Joules at 5+KV. They don't mess with that fence after that.Big Macs - 99 cents