Need input

[kmcmahon]

New construction (two years old). A ranch style duplex Adult care home (manufactured)

Two inline meters feeding two disconnect boxes on the exterior with one 100amp breaker in each box.
Basement service panels (one in each basement) have a 200 amp panel with a 200amp main in each panel. Service wires feeding these panels are 1/0 AL
Obviously, it's maximum rating based on the outside disconnect and service feeder is only 100amps.

Question is, why the 200amp main breaker? I inspected 4 duplexes for the same client and two had this setup (next door to eachother).

[Marc D. Shunk]

That 200 amp breaker in the indoor panels is only serving as a convenient disconnect means, and not any sort of overcurrent device. The real overcurrent device is the 100 amp breaker in the weatherproof enclosure outdoors. I would be willing to bet they used 200 amp rated panels indoors so that they could get a big generous panel with lots of "slots". There's no violation, but it does sorta make you pause when you're looking at it. Most 100 amp rated panels are only 20 spaces, with 30 sometimes being available. You can get up to a 40 or 42 slot 200 amp panel. Sometimes, the 200 amp panels are available for so cheap as a "builder pack", that the price is hard to pass up.

This indoor panel is functionally a subpanel now, so hopefully you double checked to make sure they have the grounds and neutrals seperated, and that panel is fed with 4-wire.

[kmcmahon]

That's what I thought....that the outdoor disconnect would serve as the main breaker and the 200amp main really would'nt be the overcurrent protection...and yes, it did make me pause and scratch my head. Just couldn't figure out why...but your reasoning makes sense. ($$).
Yes, the separated ground/neutral also caught my eye, then of course the lightbulb went on that the exterior disconnect was the main and these were now subpanels.

Thanks for letting me bounce it off of you!

[Paul W. Abernathy]

I agree as many times they need the additional space and compared to the price at the supply house it is cost effective to get the builders packs for less and include breakers with the purchase.

Just make sure all the grounding and so on has been done correctly at the outside disconnect enclosures as well.