On Mon, 31 Oct 2016 13:35:20 -0700 (PDT), wrote:

On Thursday, October 22, 2009 at 9:02:51 AM UTC-7, JayB wrote:
This came up elsewhere and I am just curious about what the answer is.

If someone has a main service panel with a 200-amp main breaker, how many
amps of service can that panel actually service?

I am probably not wording this correctly, but I thought that I remember
something about a 200-amp main breaker actually being okay for 400 amps of
service since there are two separate circuits coming in (a 240-volt service
split into two 120-volt circuits in the panel box).

If you apply 240-Volt to the load and have 200 Amps current, you've got 48 KVA. If you apply 120-volt and have a 200 amps, you've got 24 KVA. If you connect 200 Amps load to each of 120-volt leg, you've got 48 KVA total.
In other words, if you balance the load and use only 120 volt
loads, you can run a maximum of 400 amps.
If you run only 240 volt loads, you can only run 200 amps