OK, resurrecting and back to the original topic, "birds eye view" of overall system design, and specifically an appropriate setup for manual and automatic switches. Sorry it's a bit long and no diagram, all I got's my phone here.
I'm purposefully ignoring details like existing setup, device/bank physical locations, wire sizes, fusing, what wires go where exactly, specific devices other than the manual switches, etc.
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My house bank is Primary, carries ALL Loads, including cranking usually.
The much smaller Backup (starter) bank/battery normally has NO Loads on it whatsoever, except for cranking the engine during Primary (house) bank failures, or when I've run it down too much to crank the engine - hopefully rare to never for either. I acknowledge the idea of having a Backup large enough to run a subset of House Loads for a while, but won't discuss that now, KISS.
I'm pretty close to the Three ON/OFF Switch Configuration
http://www.pbase.com/mainecruising/image/154153780.jpg
but I want to keep the "Primary/normally-unused Backup" principle, rather than the more traditional House/Starter design.
Backup starter is kept floated via Echo or ACR off Primary (actually my Alt is dual output, but I think that's also OT for now).
All non-Alternator charging Sources are on the Primary bank. For now that's just the Shore charger; I may in future add solar or wind, magic Unity free power from water, etc
See Switch A below for Alternator-based sources.
And links to the right Blue Sea switch for each would be most appreciated.
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Switch A: big red 1/2 key, switches *all* Loads & Sources together
1 labeled "Isolate backup bank" (normal, Primary is connected) vs 2 "use Backup" (rare exceptions, Primary disconnected). Note ACR/EC bypasses this isolation for charging the Backup (starter).
I don't see any reason I'd ever need to Combine banks here, can have a personal power jumpstart pod for belt & suspenders, could even use jumper cables in a pinch I s'pose.
And I don't see the use of a global "ALL Banks Off", in fact it would be dangerous if someone did that while Alt was HO'ing right?
Speaking of Alts, and I am very unsure about this: Alt-based Sources (in future maybe also a smaller dedicated genset, off-topic for me here) are tied in, along with "All Loads", to a Common point on this Switch A.
Other than this requirement for a Common for the Alt(s), this would just be a very robust 1/2 switch, make before break correct? Please let me know (link?) if a suitable switch type like this exists.
And if I've lost the plot here, please tell me why this is not a good idea. If it's just $$, I think I'd be willing to spend a bit more (relay, solenoid?) to ensure I never take a running $$ Alt off Battery Load.
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Switch B: ON/OFF for all House Loads, like a Master breaker, but only for ALL loads not essential for running the engine, safety, comms, navigation etc, AKA no Boat Loads. This switch could in fact be a circuit breaker, right?
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Switch C: Same sort, but for all Boat Loads which are safe to turn off when not going anywhere long-term.
Only exceptions would be an "always on" circuit for 24x7x365 security/safety systems (no need to discuss that list here). These to be hardwired to same Switch A Common point as the Alt(s)?
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Switch X: one ON/OFF for each charging Source's circuit, to isolate in case of that Source's drastic failure, including one for the combining ACR/EC. Suggestion please for doing a manual "combine charge" if the ACR/EC fails?
For Alternators, this just turns off Field current? Or should it be set up in conjunction with an ON/OFF for AO to isolate the Alt completely; if so, do I need some sort of a delay in there?
For Shore power, both before and after the charger. Dunno about wind & solar?
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Switch ?: *really* not sure on this, but I think would like to be able to selectively isolate expensive and potentially sensitive electronics from the starter's cranking noise /spikes /brownout, and maybe from other even bigger "noisy" loads, e.g. washer/drier, big microwave or induction cooker?
Is it possible to filter/isolate these noisy Loads there?
If not, then one solution, rather than going back to House/Starter, might be to take these devices off the two main House and Boat Load circuits and move them to the "always on" group circuit.
Give them a smaller, dedicated "Sensitive Secondary" battery/bank, maybe auto-isolated from Primary by something like a switched relay triggered by starter ignition ON, or the oil pressure switch, if that's a prereq for cranking.
Obviously just noob spitballin' here. . .
All comments and suggestions would be most appreciated!