Jos,
The principal reason why there is no switch for the fuel pump supplied
directly from the alternator is so that it cannot be inadvertently turned
off -- this would require the breaker to be pulled (or fuse removed).
Issue 4 of the circuit diagram was developed following an incident
experienced by Andy Draper when giving a demonstration flight in a
914-powered Europa. During the pre-landing checks the handling pilot
switched OFF the number one pump, instead of switching ON the number two
pump, with a result that Andy did not wish anyone else to experience...
Mike
-----Original Message-----
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Jos Okhuijsen
Sent: 26 July 2006 19:37
And i would like to repeat myself:
The chance that the (too?) small capacity generator on the rotax would
"run away" and fry something is less then an OV protection killing a
healthy system.
OV protection on the rotax setup is only introducing more failure prone
components.
In the Europa supplied circuit diagram, one pump is switched from the main
bus, so will keep working if the alternator switch is off, and the master
switch on. The other pump is fed directly from the regulator output, and
will keep running as long as the engine runs, whether or not the master
and or the alternator switches are on or off. In my humble opinion this
seems to be reasonably redundant, because i can't think of a single
component that would kick both pumps out of operation.
The only addition that i would like to have here is a switch or pullable
breaker for the directly connected pump, because in case of an engine fire
while flying, it would not be possible otherwise to kill both pumps to
stop the fuel flow.
The only thing i would leave out is the master relay. The master switch is
easily rugged enough to switch the full load of this low capacity system.
Is there somebody under us who could redraw the Europa supplied diagram to
something easier readable? It is a beast to understand the way it is
presented.
--
Kind Regards,
Jos Okhuijsen
workshopcam http://www.okhuijsen.org/plane
http:www.europaowners.org/kit600
mono xs, top on, gear in, tail wheel in, wings set, flapdrive in, tail
closed, tailwheel in, tail top in, blue stuff filled, sanded and primed,
fuel system in, doors done, windows in, sanding and filling the fuse and
wings.
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