I should point out that I worked as a control electrician and was good enough that other electricians would ask for my help with control wiring challenges. I've done controls for pharmaceutical laboratories that handle dangerous pathogens. I passed the field Underwriters Laboratory Inspection on both of those. I also worked for 2 years as a fire alarm installation and repair electrician which involved a lot of control work to integrate the fire detection with elevator, kitchen hood system, fire sprinkler controls, and central station signalling systems.
I share all that to say to anyone reading the control schemes above that I AM, IN FACT, A PROFESSIONAL CONTROL ELECTRICIAN! Even another electrician who has not done extensive control work should not try to devise a power transfer assembly because it is literally a devastating injury and death prevention task. I'm not being arrogant in taking this task on. Life and death control systems, such as elevator control and fire alarm systems were my bread and butter for years. I know how to make and read ladder diagrams and control schematics. Attempting to design a one off power transfer control assembly would not be something most electricians would know how to do and, more importantly, know how to test. I'm not going to describe how transfer assembly testing is done less I tempt unqualified people to attempt it. It requires tools and equipment that most electricians do not have access to, let alone most AROs.
As too why I left solar power for my home to last, it is because of it's cost and the amount of work required. My order of back up power improvements, to my home, is based on short term effectiveness followed by long term effectiveness but only from a continuity of emergency radio operations point of view. Making the changes in the transfer equipment would go gradually from strictly manual; which is what I have now; to remote manual. Then from remote manual to partial automatic. And from partial automatic to fully automatic transfer.
Now that you made me look at this again I'm thinking that I will bypass the middle step and go to fully automatic with load shedding. That will save a lot of work and maybe lower the total costs. What may push me right back to a laboratory listed 200 ampere Automatic Transfer Switch (ATS) is the possibly prohibitive cost of 200 ampere and 30 Ampere solenoid trip breakers needed to open the Service Disconnecting Means breaker, which would disconnect the entire building from utility power; and shed the Air Conditioner load which, at least for now, would not be within the power budget of the present generator. I have not priced them yet but I seem to remember, from my working electrician days, the cost of solenoid trip breakers being quite high.
I don't know if I ever told you that I've done radio equipment shelter builds from Tierra del Fuego to Alaska and from Uganda to French Frigate Shoals. Almost all of those involved a solar power array, charging controls, and battery bank. Some of the other power sources that we used were wind generation, thermal electric, and even water power on one site. Water power is a maintenance hog so we had to have a dammed good reason to resort to that. Many of the sights had some sort of Engine Alternator Set (generator) for back up power. LP gas was the fuel of choice for those. It will store without deteriorating almost forever or at least until the container corrodes through from the outside. It is also gentler on the engine itself than most other fuels and yet still has fairly high power density in Volt Amperes per pound.
In the deployment arena I would prefer to add in solar as soon as possible but as I'm sure you know that is fairly pricey to do. Improving on what I already have would be more cost effective in the sort term. I have an entire box of used folding solar panels here that I obtained from the left overs of a development project. I've just never taken the time to pull them all out, test each one for function, and begin to acquire the other parts of a transportable solar charging system for batteries.
Perhaps you would be willing to help me get to work on that after the pandemic crisis has abated. One of my hesitancies is a complete lack of experience with transportable systems.
Tom Horne W3TDH