As the title states, there was a 100 amp disconnect at the exterior, which fed a 200 amp sub panel inside (which fed a 60 amp sub panel). The 200 sub panel was fed with #1 copper SE wires. 2,100 sf house with electric water heater, stove, oven, AC condenser etc. Now technically the set up is “o.k.”, as the wires are sized properly for the 100 amp main, correct? But, in theory, the “loads”/distribution of the 200 amp panel (along with the 60 amp sub panel) would likely be “excessive” for the 100 amp main wires/disconnect, but an electrician would have to determine that, correct? The subs weren’t wired up properly, which warrants repair by an electrician, and I want to include something along the lines of what I just iterated. Would you just say something like that or what do you say? TIA.
It looks like a lot of stuff is electrical: water heater, stove, oven, dryer? 100amp for 2k sqft is pushing it in 2020. Any ACs? You could trip the main if you are not careful. You could write it up and advise the client that the main service may be undersized for the electrical appliances installed and or at the capacity and any additional heavy appliance may require service upgrade. 100amp is the bare minimum, today. BTW, the service should be based on load calculation and with some room for future upgrades.
Possibly, recommend that the qualified electrician do a load calculation on the electrical system to ensure that there is adequate service for the home while there making other corrections.
Thank you both for your help, I appreciate it!
There are many issues with this installation. Here’s just a few, there is no GEC landed at the service disconnect, the neutral in the disconnect is not bonded, the SEC’s are all white, the panel neutral is bonded and shouldn’t be, the panel feeder neutral is bare, etc.
Yes, I know, I was just inquiring about the topic at hand 
Thank you though. One question on your response though. The meter base was grounded with the GEC. As long as the service disconnect gets the bonding screw installed, that should be fine/compliant, no?
That’s correct, the GEC can terminate at any point between the service drop and the service disconnect. If the utility allows it in the meter enclosure then that’s a good place to land it. Answering your initial question I agree that the 100 amp service seems a bit small but as mentioned a load calculation would be needed to make that determination.
Thanks again, appreciate the help & advice.