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From: "Steven W. Boese" <SBoese@uwyo.edu>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Date: Sat, 21 Nov 2009 11:40:44 -0700
Subject: RE: [FlyRotary] Re: No start
Thread-Topic: [FlyRotary] Re: No start
Thread-Index: AcpqzxGiNQcY5FmTSASbVoSnBv4uSAAB6O/w
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Steve,

I was able to produce symptoms similar to what you describe by inserting a =
1.5 V flashlight battery into the CAS return wire such that the CAS end of =
the wire was 1.5 V more negative than the CAS return wire going to the EC2:=
 =20
CAS ----- battery ++++ EC2

The opposite polarity didn't cause problems.  With the battery installed, t=
here are one or two sparks when starting to turn the CAS and then no more s=
parks until the CAS sensor is turning significantly faster than would be th=
e case when turning the engine with the starter.

It seems that you may have the CAS return grounded in addition to the conne=
ction to the EC2.  If this is the case, then the voltage drop from the star=
ter current may shift the CAS return voltage similar to what I did with the=
 test setup.  If I disconnect the CAS from the EC2 at the EC2 connector, al=
l the CAS wires show infinite resistance to ground.  It might be useful to =
see if your wiring is similar.

Steve Boese
 =20