Icebound wrote:

3. How does pulling the BAT half of the master during engine-running,
reconcile with the caution about pulling battery power on a boat/automobile?
( There ...boats/cars..., isolating the battery from the alternator while
running, is said to cause the alternator to blow diodes and fail. )

You should not do it, unless in an emergency situation.

The battery buffers the voltage spikes originating
in different electro-magnetic equipment on board. The
avionics are in danger if the spikes are not discharged
into the battery.

Pretty often the master switch halves are interlocked
so that it's not possible to keep the alternator on
without the battery.

The alternator diodes are not the only endangered
semiconductor components. There are many other
diodes, transistors and integrated circuits feeding
from the power bus.

HTH

--

Tauno Voipio (CFII, avionics engineer)
tauno voipio (at) iki fi