How to ground my metal building.

[jigs_n_fixtures]

For future readers planning a metal building: Add a bare copper #4 to at least three footings, tied to the rebar in the footing and the anchor bolts. If you are placing a reinforced concrete floor, ground two footings, and install one lead bonded to the reinforcing steel for the slab.

When I was building subdivisions, we installed the meter socket and service panel mounted to a metal frame made of 3-1/2 inch steel channel. The frame went down into the footing and slab, and connected to the reinforcing with u-bolts. This gave us a grounded meter pedestal, in line with the garage wall. The power company would give us permanent power, with just the slab and the meter pedestal in. The electrical sub, would come off the breakers for the water heater, drier, and garage receptacle breakers, and install two 240-volt, and eight 120-volt receptacles below the panel between the legs of the pedestal. That gave all the trades power for their tools, and battery chargers, during construction.

 

[grsthegreat]

Grsthegreat. If I ran the 4th wire which would have been a ground wire. I’m thinking I would have separated the neutral and ground at shop panel and still ran a ground wire to a ground rod.

I can still pull service wire back out and run a ground with it. Not a very hard pull. If I do what size ground wire do I need? #4 or #6 thhn. Will be a 45 foot pull.

Depends on the amperage involved, but 6 more than likely will be ok.

 

[workinonit]

Here's a good way to ground.

 

[workinonit]

It's hard to see the water but the red hose is to pump the water out with. Sorry. I had to post this since we just found it.

 

[grsthegreat]

NO ONE EVER SAID ELECTRICAL CONDUIT IS WATER PROOF. i have had to blow so much water out of pipes....its insane. especially when the water freezes and your trying to fish thru a pull line.

 

[4570Man]

NO ONE EVER SAID ELECTRICAL CONDUIT IS WATER PROOF. i have had to blow so much water out of pipes....its insane. especially when the water freezes and your trying to fish thru a pull line.

It’s surprising how many people actually think it’s dry inside.

 

[rickyb01]

LD1

I installed a electrical pedestal behind my shop. The power from the co-op comes from the powerpole to the pedestal. They required me to have 2 200 amp meters. I installed 200 amp meter/main combos at the pedestal. One for house and one for shop. They have a 200 amp breaker in them.

so I’m talking from my 200amp meter/main that has a 200 amp breaker going to shop that has sub panel with no main breaker.

 

[rickyb01]

Depends on the amperage involved, but 6 more than likely will be ok.

I’m going pull that 3 wire back out and add a #6 wire to it. I couldn’t find #4 but Home Depot sold #6 by the foot. After doing that I will separate my neutral and ground.

do I still ground the sub panel in shop to ground rod? Do I still bond metal beam to ground lug in panel? Thanks

 

[Fallon]

For future readers planning a metal building: Add a bare copper #4 to at least three footings, tied to the rebar in the footing and the anchor bolts. If you are placing a reinforced concrete floor, ground two footings, and install one lead bonded to the reinforcing steel for the slab.

When I was building subdivisions, we installed the meter socket and service panel mounted to a metal frame made of 3-1/2 inch steel channel. The frame went down into the footing and slab, and connected to the reinforcing with u-bolts. This gave us a grounded meter pedestal, in line with the garage wall. The power company would give us permanent power, with just the slab and the meter pedestal in. The electrical sub, would come off the breakers for the water heater, drier, and garage receptacle breakers, and install two 240-volt, and eight 120-volt receptacles below the panel between the legs of the pedestal. That gave all the trades power for their tools, and battery chargers, during construction.

That's called a Ufer ground or concrete encased electrode. https://en.m.wikipedia.org/wiki/Ufer_ground

Concrete protects the rebar & is more electrically conductive than dirt. They work well & are pretty easy to install if you do it right before you pour the foundation.

 

[CobyRupert]

So the building’s panel is a sub-panel. It’s a fed from the first disconnect point from the service point, which is a 200 amp breaker at the meter pedestal.
Everything, past that breaker is the owner’s realm and not subject to co-op’s service requirements, just the building inspectors. The question is where is the system neutral and ground bounded?
It should be at the 200 amp breaker.
Ground and neutral bus (or any conductors) should only be bonded together at one spot.
So if bonded at main disconnect breakers at meters, the neutral bus and ground bus of both barn and house panels shouldn’t be bonded at those panels.
Ground rod is needed where bonded. Ground round for ground bus only needed at house and barn panels if ground and neutral are bonded at meter and disconnect switch location. Building’s metal post should be connected to building’s panel ground rod either directly or by connecting two ground rods.

I hope when you re-fed the house from a new 200A breaker at the new meter, that they “unbonded” the neutral and ground busses in your house panel, and check that no green wires are terminated with any white wires on a single bus. This is a common oversight when changing service disconnect locations.