I thought perehileon design had a circuit for doing this, but in looking at
there web site, I couldn't find it. Eric Jones monitors the list -- Eric?
Bill Schertz
----- Original Message -----
From: "Harley" <harley@AgelessWings.com>
To: aeroelectric-list@matronics.com
Sent: Monday, November 16, 2009 11:30:35 AM GMT -06:00 US/Canada Central
Subject: Re: Fuel pump control
Instead of a pressure switch, how about a flow switch on the input side of
the mechanical pump...
Harley
Jeff Page wrote:
I just came across a notation I made quite a while ago, after noticing a ne
at idea, probably on this list.
It utilizes a low pressure switch to provide an "automatic" mode to the ele
ctric fuel boost pump, so that if the engine driven pump failed, the electr
ic one would be powered up.
This seemed like a great idea at the time.=C2- It would likely mean an en
gine hiccup, followed by the fuel pump on LED illuminating - much better th
an the pilot conjecturing the engine failure is due to fuel starvation and
manually turning on the pump (would be a checklist item).
However, looking at the schematic as I drew it, as soon as the electric pum
p provided sufficient pressure, the low pressure switch would open and the
pump would shut off, and then back on, and then off.=C2- Ooops :-(
Is it worth fabricating a little latching circuit to provide this automatic
operation, or better to keep things simple ?
I don't do hard IFR, and manually turning on the fuel pump switch in most c
ircumstances would be sufficient to avoid an unpleasant landing.
Thoughts ?
Jeff Page
Dream Aircraft Tundra #10
