You'll get folks to dispute this since one panel is not carrying the entire load, but here even for a 400A service with two 200A panels we would use 4/0AL (2/0CU) to feed each panel.

If using cable then yes, you need two hots, a neutral and a ground. Typical would be SER cable.

 

Is it against code to have 2 200 Amp panels for 400 Amp service?

Is it recommended to have two 200 Amp services with one feeding each 200 Amp panel? If this were done, wouldn't we need two meters with separate service cables from the utility? This just seems like it would add cost more than anything.

 

Is it against code to have 2 200 Amp panels for 400 Amp service?

Is it recommended to have two 200 Amp services with one feeding each 200 Amp panel? If this were done, wouldn't we need two meters with separate service cables from the utility? This just seems like it would add cost more than anything.

 

A 320/400 amp service with one meter, feeding two 200A panels, is absolutely typical and common.

 

Did you do a load calculation? Do you really need a 400A service?

 

I've done a load calculation and I don't need 400 but I need more than 200. My garage shop will have several 240v 30-50 Amp dedicated circuits (table saw, dust collector, welder, electric heater, etc.). I decided on going with 400 as I plan to add a separate Morton building and want to have the ability to add service to the Morton building at that time.

 

But one panel would not be a subpanel off of the other, 200 amp, panel.

Both 200 amp panels would be "main" panels, installed next to each other so the top (main) breakers of both may be flipped off at the same time.

 

One of the panels will be installed on the other side of the basement which will be 100' away from the SE so my assumption is that the panel located 100' away would be considered a sub-panel and installed as such.

 

Then you will need a disconnect next the the other panel. The disconnect will be wired as a service as well as the 200 amp main breaker panel.

 

My assumption is that the sub-panel would have a main breaker similar to the main panel. Does this suffice as the "disconnect" you mentioned?

 

The main in the second panel will just be a redundant switch. The services must be grouped so you will have a disconnect next to the first panel.

 

If I may summarize...A disconnect will be placed next to the main panel. The disconnect will be fed from the main panel and the sub-panel will be fed from the disconnect. I can have a main breaker in the sub-panel if I want to be able to disconnect power to the sub-panel at the sub-panel. Is this correct? What type of "disconnect" is required in this case?

 

The disconnect will NOT be fed from the main panel. It will be fed from the 400 amp service.

 

OK. Then why not just feed from the 400 amp service to the 2nd 200 Amp Panel and treat them both as separate 200 amp main panels each with a main breaker?

 

The services must be grouped adjacent to each other. Since you want one panel in a different location you need a disconnect .

 

Since I'll have more than 6 breakers in the 2nd panel, I believe I will need a main breaker at the panel in addition to the disconnect at the main panel. Is this correct?

I'm just curious, but is this 2nd panel considered a main panel since it's not coming directly off the SE panel?

What type of disconnect is required/suggested for the 2nd panel?

I really appreciate all of the great information you've provided!

 

You can't a have a 100' length of unfused conductors coming right off the 400 amp services. Plus you need to be able to turn all the power from one location with no more than 6 switches.

 

With that setup the services are grouped at the meterbase. Both interior panels would be wired as subpanels with 4 wire feeds.

 

Is there any advantage or disadvantage to this setup?

 

Saves the cost of a disconnect

 

and the cost of main breaker panels.

 

A 320/400A meter base with main breakers is quite expensive, so I don't really see any cost savings there. It is simpler to install and cleaner though.

 

I have seen main breaker panels cheaper than MLO panels.

 

Very well could be in a single phase panel as a Main CB is more common.

 

All - I really appreciate all of the great information provided here and the very helpful responses. I have decided to go with a 320/400 Meter Base/Combo with 2-200 AMP Breakers along with 2 Main Lug Panels rather than 2 Main CB Panels.

Now, I'm trying to decided on what size main lug panels to go with. I've put together the circuit configuration below. Do I go with 30-30 panels?

 

Many 200 amp panels are 40 circuits. It does not hurt to have more room.

 

:thumbsup:

For the difference in cost go with the maximum number CB's allowed 40.

 

Given that I plan on adding a Morton building and generator hookup, do you suggest going with 40-40 full-size main lug panels?

Additionally, do you see any issues with the branch-circuit setup I've put together?

 

Additionally, do you see any issues with the branch-circuit setup I've put together?

First thing that jumped out is GFCIs. You missed the garage receptacles. Also, the basement receptacles, if the basement is not finished.

Also, if you are IDing GFCIs, why are you not identifying AFCI protection?

 

I've been reviewing code and haven't gotten to the point where I 100% know what needs AFCI protection. My understanding is that AFCI protection is required on all circuits supplying wall outlets. Is this correct and does it apply to the bath and Kitchen small appliance circuits?

 

What edition of the code is adopted in your area?

 

National Electric Code /2008 as referenced in Section 1201.1.1

 

My understanding is that AFCI protection is required on all circuits supplying wall outlets.

When the code says outlets, they are talking about any point of use, not "wall outlets". Those are referred to as receptacles or receptacle outlets. So the lighting circuits in the dwelling will require AFCI as well.

The 2008 requirements,

"(B) Dwelling Units. All 120-volt, single-phase, 15- and 20-ampere branch circuits supplying outlets installed in dwelling unit family rooms, dining rooms, living rooms, parlors, libraries, dens, bedrooms, sun rooms, recreation rooms, closets, hallways, or similar rooms or areas shall be protected by a listed arc-fault circuit interrupter, combination-type, installed to provide protection of the branch circuit."

I would interpret that to include finished rooms or areas in a basement.

Looking at it the other way, kitchen,bathrooms, laundry and the garage don't need them.

 

When the code says outlets, they are talking about any point of use, not "wall outlets". Those are referred to as receptacles or receptacle outlets. So the lighting circuits in the dwelling will require AFCI as well.

The 2008 requirements,...........

And the 2014NEC goes insane over the top with these requirements, like refers and DW's as well. Pretty much everything in a dwelling.

 

I've modified the image to replicate a 40-40 panel to show how the panels will be setup. I've also added the GFCI and AFCI call-outs. I've tried balancing the load as best I can but I'm not sure it's best practice or not. Any input on this would be great.

 

Why would 40 be the maximum number allowed in this case ?

I thought the 42 circuit rule got removed in 2008. What am I missing ?

 

It was.
I was just at the supply house this AM and they had a new Cutler Hammer main breaker BR series panel, 60/120!! The thing was over 4 foot tall.