Message-Id: <3.0.3.32.19981018190940.00ca778c@olsusa.com>
Date: Sun, 18 Oct 1998 19:09:40 -0400
To: lancair.list@olsusa.com
From: Lynda Frantz <LFrantz@compuserve.com> (by way of Marvin Kaye <marvkaye@olsusa.com>)
Subject: Optical fluid level sensor
Mime-Version: 1.0

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The float switch from A/C Spruce  which gave me all the problems are made
by Compac Engineering.  A/C Spruce sent the a model which I found  by
testing was not resistant to gas. It turned out to be made from
Polypropylene.   I ordered another model direct from Compac ($35 each) made
from  KYNAR PVDF and although it was resistant to gas I had problems with
tripping fuel transfers in turbulance and turns even when the fuel tank was
full.  Note that there is no delay built into the float switches.

To solve the problems I swaped the float sensors for optical sensors made
by Kinematics & Controls Corporation (sorry I don't have their address or
telephone).  You can find them through the Thomas Register.  The custom
sensor drawing reference is 5253-GC-0002 to my specifications and were a
four wire output +14, Ground, open collector and open emitter.  The output
transistor sinks when dry after a 5 second delay.  The electronics are
encapusulated in epoxy in a polysulfone fitting which screws into a 3/8"
NPT on the side of the tank.  The cost was $90 each.

Jim@angle-of-attack.com