[prairieschooner]

Tuga,
I would rather see the Battery Switch Disconnect the Batteries from ALL Systems. Actually on a boat it is an ABYC Recommended Standard in Yachts, although does allow an exception for Charging Equipment. This way you can disconnect the Batteries from the System. I realize that the Fuse should interrupt the System but I have made that change on our '82 and feel better knowing that I can Disconnect the Batteries.

Item #2;
11.6.1.2 Battery Switch

11.6.1.2.1

A battery switch shall be installed in the positive conductor(s) from each battery or battery bank with a CCA rating greater than 800 amperes.
EXCEPTION:
Trolling motor conductors connected to dedicated trolling motor batteries provided with overcurrent protection at the battery and a manual means of electrical disconnect separate from the trolling motor controls.
NOTE: Conductors supplying the following may be connected to the battery side of the switch (See FIGURE 11 ):
a. Electronic equipment with continuously powered memory;
b. Safety equipment such as bilge pumps, alarms, CO detectors and bilge blowers; c. Battery charging equipment.