In two airplanes that I own(ed), (Piper Seneca and Piper Cherokee) the hobbs
is poswered directly from the battery, through an inline fuse, and through
an oil pressure switch on an engine. Turning off the master would have no
effect.
"Jose" wrote in message
.com...
One trick an instructor showed me... cut the master switch off. The
engine keeps running... and no time logged.

Doesn't the hobbs usually bypass the master, like the clock?

I rented from one outfit that connected the hobbs to the master, and
nothing else (no oil pressure sensor). I clicked off a few tenths doing
my preflight, setting up radios, etc, before I caught on.

Jose
--
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