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I want to start by saying I’m not an electrician. I’m building my own home and I’m doing the electrical myself. This is completely legal in my state of Maine. I have a question on how to properly ground an emergency shut off switch.

I want to start by giving some information on the house and my electrical set up. First, I have my meter mounted on my electric pole(which I own). There is a panel with a 200 amp breaker and a few outlets on the pole. It has its own ground rods. From there, power goes underground to an emergency disconnect mounted on the house. From there it goes to the middle of the house where I have my 200 amp sub panel and all my breakers.

From the pole to the disconnect I have urd cable. It has 3 4/0 and a 2/0 ground. The state inspector wants to see another set of ground rods next to the house. The issue is that the emergency disconnect only has a spot for one ground coming in and one ground coming out. I have two grounds. One from the pole and one from the ground rods next to the house.

So what is the correct way of linking all this together? Should I add a lug inside the panel? Or should I connect the ground coming from the pole directly to the ground rods by the house? Another option is I take the ground from the rods next to the house and run a cable directly to my panel inside and completely bypass the emergency switch. Are there other options? Any input is much appreciated. I can take pictures of the setup if needed. Thank you.

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From the pole to the disconnect I have urd cable. It has 3 4/0 and a 2/0 ground. The state inspector wants to see another set of ground rods next to the house

The inspector is correct. Every outbuilding needs its own set of ground rods. What is your rationale for omitting them at the house?

The issue is that the emergency disconnect only has a spot for one ground coming in and one ground coming out. I have two grounds. One from the pole and one from the ground rods next to the house.

An easily resolved issue. Since it has a metal enclosure, it is considered a valid grounding point provided you attach to it correctly. You can read the disconnect labeling about accessory ground bars which may be approved for the disconnect, which in practice means they have pre-drilled, pre-tapped mounting sites made to fit them… or simply attach a lug to the metal chassis of the disconnect. Or use a feeder tap. Or use a split bolt. Or pigtail it with a floating lug, since it's ground you don't need to use the costly, insulated Polaris.

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Before I complete an answer, please take photos if you can. Reasons are A) Your breaker panel has a neutral bar where ALL of the white neutral wires connect. B) There is normally a bare 8ga or 6ga wire from the neutral block to the ground block. This is mandatory as your grounding rods connect to the gnd bar with 8 or 6ga solid copper wire.

Note that a photo will confirm that your breaker panel is to NEC code, such that you only need to add the ground wires as mentioned above. Neutral MUST also be grounded at the transformer that supplies your power. If not complete to this point you need to call a master electrician to finish the basic.

@Joelp OK, if a sub-panel it still needs a ground wire back to the main panels grounding bar. Note that the grounding rods connect to the main service entrance panel only.

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  • I can take pictures in the morning. I do have a neutral bar and only neutral go to it. Correct me if I'm wrong but I believe the panel inside the house should not be bonded because it's a sub-panel
    – Joelp
    Commented Feb 24 at 4:00
  • I do have the 2/0 ground coming from the panel at the pole, then through the emergency disconnect, finally into the sub panel inside the house. The only ground I haven’t tied in is the one for the rods beside the house. I’m assuming they get a 6 ga wire directly to the panel inside the house. The state inspector has been out. I wasn’t finished when he randomly stopped in but he has seen most of the work and there are no issues inside the panel.
    – Joelp
    Commented Feb 24 at 4:14
  • Then you have little work to do. The grounding rods are mandatory. They prevent grounded appliances from being a shock hazard....
    – Sparky256
    Commented Feb 24 at 4:20
  • @Joelp what make and model is your emergency disconnect? Commented Feb 24 at 5:11
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    Under the new rules, since OP has branch circuits coming off out at the meter, that has to be the service disconnect / Neutral-ground bonding point, and the house must be a subpanel. NEC 2020 230.82 breaks out what's allowed as a service side tap. Commented Feb 25 at 1:26

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