Message-Id: <3.0.3.32.19981012094947.00af0fd4@olsusa.com>
Date: Mon, 12 Oct 1998 09:49:47 -0400
To: lancair.list@olsusa.com
From: Sven.Jerlhagen@ecs.ericsson.se (by way of Marvin Kaye <marvkaye@olsusa.com>)
Subject: 320 fuel system reply
Mime-Version: 1.0

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>>
Any automatic system has to be designed such that no single failure will
create a catastrophe. Failure of a relay is handled fine by your warning
light. But when the lower float switch fails (it will happen eventually)
you will not notice. Since you will be used to your fuel system handling
itself,
the first thing you will notice is when the engine stops. Failure of the
circuit
breaker or wiring means the same. The system should have two circuit breakers,
one for driving pumps and automatics, and one for a completely separate
monitoring system. The simplest mod to your system would be to add a
cb/fuse, and 
 third float, or drive the relays from the upper float only.

If you can't do a safe redundant automatic system (i.e. fails gracefully), I
prefer the standard system.

SE-XOP Sven