400A Meter (320 continuous) with 2 outdoor service panels (w/ main disconnects)

[roger]

Mine is clueless, but the localities agree, because the tag makes it inaccessible.

And so in their opinions the other conductors aren't a concern.

 

[LarryFine]

And so in their opinions the other conductors aren't a concern.

Mayhaps they think only GEC terminations need inspection.

 

[roger]

Mayhaps they think only GEC terminations need inspection.

Yep, that's the one that will cause mayhem for sure

 

[Eliasc94]

At this point I just want to install a grounding busbar in the garage and take all of the GECs to it.

 

[LarryFine]

At this point I just want to install a grounding busbar in the garage and take all of the GECs to it.

Then the unbroken/unspliced rule applies only to the conductor from the bar to the main electrode.

 

[Eliasc94]

Then the unbroken/unspliced rule applies only to the conductor from the bar to the main electrode.

True. I just feel like there isn’t really a fully safe and compliant install with a 400a meter and 2 service panels. I wish my company would just let us install a 400a service panel….

 

[LarryFine]

I just feel like there isn’t really a fully safe and compliant install with a 400a meter and 2 service panels.

Why?

 

[Eliasc94]

Why?

I don’t know. Feels like it’s hard to tell who to trust. I could blindly follow my boss who has been wrong about code many times but I want to do things right. I come here looking for answers and I’m more confused than ever. Maybe you guys are giving me the answer and I’m missing it.

 

[roger]

I'll try to post some illustrations that may help later tonight or in the morning, I'm not at my PC right now.

 

[LarryFine]

I don’t know. Feels like it’s hard to tell who to trust.

I meant which part of an installation do you feel is difficult to comply with code about?

 

[Eliasc94]

I meant which part of an installation do you feel is difficult to comply with code about?

I think grounding/bonding two panels using the same GES. I’m also reading elsewhere online about the parallel neutral path and it almost seems unavoidable with this configuration.

 

[mtnelect]

I always use a "Bused Gutter" then drop down with panel(s) or disconnect(s).

 

[Eliasc94]

419.1.2 Meter Mounting Devices for Self-Contained Meters rated at 320


Amperes: Meter mounting devices rated at 320 amperes shall not be used where the anticipated load and service entrance conductors have a rating of 200 amperes or less. No more than two conduit and two sets of Service Entrance Conductors shall be used on the line side and no more than two conduits and two sets of Service Entrance Conductors shall be used on the load side of the meter mounting device.


The conductors do not have to be the same size for line and load. If the Service has more than one (1) Service Disconnect, the load side Service Entrance Conductors shall feed a line gutter. In addition, the Meter Mounting Device shall not be used for a supply side tap to Interconnect Electric Power Production Sources. The Customer or Customer's contractor shall make all_connections to the Meter Mounting Device, except for instrument transformer rated installations. (For more information on 320 Amp meter mounting devices, see ARTICLE 418.2 and Illustration 19A & 19B on page 52.

I guess I also need to use a gutter if that matters..?

 

[Dsg319]

 

[Dsg319]

Here are some illustrations. Sorry for any confusion.

 

[zbang]

I think grounding/bonding two panels using the same GES. I’m also reading elsewhere online about the parallel neutral path and it almost seems unavoidable with this configuration.

You need a single GES anyway- all the qualifying grounding electrodes* need to be bonded together, so in essence those make a single GES for everything. Not quite on-point, but also imagine where a structure has a 408Y service, a 208Y service and a 240D service; they're all going to use the same GES.

*rods, Ufer, water pipes, plates (does anybody still use those?), etc

You may have parallel paths, but those are acceptable to the code in this sort of specific instances.

 

[electrofelon]

I don’t know. Feels like it’s hard to tell who to trust. I could blindly follow my boss who has been wrong about code many times but I want to do things right. I come here looking for answers and I’m more confused than ever. Maybe you guys are giving me the answer and I’m missing it.

Many people struggle with grounding and bonding multiple service disconnect enclosures. I am not sure why, it says right in the code 250.64(D) "Building or Structure with Multiple Disconnecting Means in Separate Enclosures"......

 

[roger]

Along with the illustrations DSG posted here is another option , just imagine another panel on the left side of the meter. Both panels will need bonding jumpers (the green screw shown), the GES can be jumped together as shown in the second illustration.

Also notice there is only on GEC that goes to the first electrode the rest are jumpers, the whole GES does not need to be connected with one continuous conductor

 

[LarryFine]

Along with the illustrations DSG posted here is another option , just imagine another panel on the left side of the meter.

View attachment 2571493

Keep in mind that many jurisdictions, such as VA, don't allow landing GECs in the meter base.

 

[Eliasc94]

Keep in mind that many jurisdictions, such as VA, don't allow landing GECs in the meter base.

I’ve only seen one area where I live require it. Otherwise I’ve always been told to avoid it.