Your main breaker should be 200A at this time. You typically do load-calc to see if you really need {400A}.

I would not be upgrading to 400A service unless you really, really need it. With today's LED lighting, energy efficient HVAC, water heaters, individual homes use less and less energy causing havoc on energy providers.

Honestly 400A service = 2x 200A service fed by 400A meter on each side. All you really need to do is upgrade meter pan and run double grounding 6' appart. As far as wire running 500MCM / $6 per foot plus cost of trenching. Call your electric company to find out. Unless you are running multiple AC units, or everything uses heat strips I would not do it.

IMHO electric company would not connect the service until they inspected and it is done properly. Nothing to worry.

"reasonable" is getting expensive. There's more to PG&Es deposit, as once designed they usually want more & often they want certified installers.

[QUOTE]Your main breaker should be 200A at this time.[/QUOTE]

The main breaker is not required to be sized to the ampacity of the service conductors feeding it, just after it.

The rest of your statement is bizarre. The grounding requirements are no different for 200 or 400A service. Two ground rods were likely required in either case.

But the comments on the necessary capacity is right. Unless you have a very large house in a very hot climate, you're probably not exceeding 200A. I have 400A service, but most of the time I'm not even exceeding 100A.

What? So in your jurisdiction you can have 60 amp service with 400 A panel and protected by 400 A main breaker.

Not required by whom? The electrical company will not hook up the service, the county inspector will never let you install the main breaker that exceeds the ampcity of the service wires. My project involved getting electrical company to upgrade transformer to quad. We have to have 500 McM in 3" conduit with 3" cap with 400 amp meter pan. The most common setup from each side of the meter run 200 amp panel =2 x 200 = 400 service. The jurisdiction I am in requires 2 grounding rods, matters not if you have 400 amp panel or two 200 amp. Was told that in the past they required a grounding loop: rod, water ground, rod looping back to the initial rod.

This is as cheap as it will ever be to do it right. Cancel some fancy finish and do it now. It will only get more expensive e the longer you wait.

Besides two grounding rod s are not bad for
a consumer. In a lightning strike you want fast discharge to a grounding ... saves more electronics , air conditioners, well pumps, TVs, computers, routers.

As far as the NEC code, the rating of the main OCD is not there to protect the service wires ahead of it. What your power company requires is distinct from what the NEC is concerned with.

As far as the code goes, a single grounding rod isn't sufficient by itself except in certain circumstances. You need a secondary electrode of some sort (which could be a second ground rod or a metal water pipe etc...). As far as the NEC is concerned this is true regardless of the size of the service or how many panels you have.

I agree with GreenDesigns that now is much cheaper to do this than in the future. If you think you'll ever want to have an electric car and a fast charger or two, then upgrading to 400A service makes sense.

If you think that this is unlikely to happen during the time that you own the house, then installing expensive services because of hypothetical future needs doesn't really make all that much sense.

Only you would know.

• >> My question is, can we just run our existing 200 amp service through our
  new 400 amp panel until a future time when we can (if we end up)
  actually having the 400 amp line run?
• > I agree with GreenDesigns that now is much cheaper to do this than in the future.

I guess I'd just put in a 200 amp main breaker for now! Just seems like common sense - or do they just not make such a thing?

You're going to spend a lot of money retrofitting a 200A breaker into a 400A panel. Unless you have some compelling reason from your inspector or the power company, there's no overwhelming reason to do this. As I pointed out, there's no compelling (NATIONAL) code or safety reason.

I had a similar problem in that my builder installed 200 Amp service by mistake (his). So he ran another 200 Amp line to a second main breaker in a second panel. The meter outside is a single 400 Amp one and it's connected to two 200 Amp runs to the house (meter panel is far from the house).

Hopefully, the meter outside has the service disconnect or the two panels are very closely grouped together.

I found this thread because I am looking at installing solar panels and an inverter, and found out that to grid tie, it is recommended to have a main panel rated for more than your actual service. I currently have an 200A service, but I want to upgrade my main panel to 400A to have a high enough rating on the bus bar. Then I would tie my solar in through an inverter to a breaker on the far end of the bus from the main. Eventually I want to own an electric car, and install enough solar panels to get a full daily charge, so as long as I'm doing a service upgrade, upgrading to 400A makes sense.

Wondering why this thread is on the pool forum????

Because one application is for a swimming pool!

Ron, to answer your comment, the two panels are about 4 inches apart.