Grounding Electrode Conductor

[Jimmy7]

If you have a 200 amp meter main on the exterior of a single family house that feeds a 200 amp interior panel with a 3 wire can you run the grounding electrode conductor from the ground rods to the meter main? The water main is plastic in this house, and the existing appliances are 3 wire.

 

[Dennis Alwon]

The grounding electrode conductor must be connected at the service. Why is there a 3 wire going into the interior panel? Is it run in conduit?

 

[jaggedben]

You can always run a grounding electrode conductor to a meter main but it sounds like you have other issues.

 

[Jimmy7]

I believe a three wire seu was run because of the existing 3 wire appliances. It seems that in my area if you ran a 3 wire you didn’t have to rewire the existing 3 wire appliance.

 

[jaggedben]

Okay, but that has nothing to do with a grounding electrode conductor.

It's hard to tell you what you need to do if your AHJ is making allowances. Under the 2020 or 2023 NEC, you could perhaps call the outside meter main the 'emergency disconnect' (see 230.85) and call the inside panel the 'service panel' and bond neutral to the 'service panel' enclosure. Otherwise, while it may be allowed in your area, the 3-wire feeder without EGC does not comply with the NEC.

But regardless the NEC would still allow you to connect a grounding electrode conductor in the outside meter main.

 

[roger]

I believe a three wire seu was run because of the existing 3 wire appliances. It seems that in my area if you ran a 3 wire you didn’t have to rewire the existing 3 wire appliance.

This your big problem, you will need to install a four wire feeder to the panel regardless of how you address the appliances.

 

[Jimmy7]

I’ve see this type of installation around here all of the time where the service has been upgraded in an older home. It’s 3 wire run between a meter main and the panel. The meter main is then labeled “Emergency Disconnect, Not Service Equipment“.

 

[jaggedben]

I’ve see this type of installation around here all of the time where the service has been upgraded in an older home. It’s 3 wire run between a meter main and the panel. The meter main is then labeled “Emergency Disconnect, Not Service Equipment“.

Then by the NEC you could still connect the grounding electrode conductor to either the panel inside or the emergency disconnect.

 

[infinity]

I’ve see this type of installation around here all of the time where the service has been upgraded in an older home. It’s 3 wire run between a meter main and the panel. The meter main is then labeled “Emergency Disconnect, Not Service Equipment“.

I did that in my own home. Since I didn't want to extend the existing GEC to outside of the house I made the outside disconnect the emergency disconnect, ran 3 conductors to the new panel in the basement, and bought the proper label for the outside disconnect.

 

[Dennis Alwon]

The newer codes allow us to use the old 3 wire cable from the outside to the inside but the outside disconnect must be labeled emergency disconnect not service equipment as shown in Infinity's post

 

[Fred B]

OP shows location as Boston, that are is under that new allowance (2020 and newer NEC) that allowed for the retaining the 3 conductor past the the "Labeled" Emergency disconnect. I think Mass. was one of the areas that pushed for this allowance when making exterior disconnects on dwelling units mandatory.
It seems weird that one piece of equipment with no other difference other than adding a label can be wired differently. But it is allowed in the code.