wrote: Ed and Joe, The diode in the EC2 allows the current from the collapse of the injector magnetic field to flow to the positive supply rail (~14V); it doesn't oppose this. A resistor allowing this current to flow would also result in a close delay since the current flowing is what = maintains the magnetic field during this delay. What is needed is a way to decrease the rate of voltage rise just after the EC2 pulse ends so arcing in the A/B selection relay is suppressed. After the relay contacts open enough that an arc is no longer possible (which = shouldn't take long) an open circuit condition now would allow the injector to close quickly. The arcing may or may not be a problem any given tim Ed =20 -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html ------=_NextPart_000_0006_01C764C9.A77BA1D0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

My original thoughts regarding a = dropping resistor=20 were the result of being bored while lying in bed with a 102 degree = fever,=20 otherwise I would have likely been working on my airplane. In the = end, I=20 believe Tracy is likely the best person to devise the ultimate = solution. =20 But in fairness to Tracy, he seems to be a rather busy person juggling = his=20 manufacturing, airplane building, technical support, and product = development may=20 not leave much time to work on this particular issue. So I threw = my 2=20 cents into the ring. My first though was an RC circuit, but = thought it may=20 not be a reasonable solution due to its Time/Decay rates.

Last point I would like to make is = anyone=20 considering using a MOV "Please read the=20 following info:"

http= ://www.iaei.org/subscriber/magazine/04_b/04_b_brown.htm

Like any solid state device an MOV is = subject to=20 degradation (quickly if the power through it is greater than its heat=20 dissipation capacity). Further, unlike many other solid state = devices that=20 fail in the off state when they loose their internal smoke - a MOV = can=20 fail in the ON state.

Sincerely,

Joe (Hoping I have not offended anyone, = or be=20 banned from FlyRotary like so many others have been from the other=20 list.)

----- Original Message -----
From:=20 marv@lancair.net=20
To: Rotary motors in = aircraft

Sent: Sunday, March 11, 2007 = 2:30=20 PM

Subject: [FlyRotary] Re: A = solution? was=20 : The truth??? / Injector flow rate mystery solved

What about = MOV's? Typical=20 transient response time measured in nanoseconds...

= <Marv>

"Steven Boese" <sboese@uwyo.edu> = wrote:

Ed and=20 Joe,

The diode in the EC2 allows the current from the collapse = of=20 the
injector magnetic field to flow to the positive supply rail = (~14V);=20 it
doesn't oppose this. A resistor allowing this current to flow=20 would
also result in a close delay since the current flowing is = what=20 maintains
the magnetic field during this delay. What is needed is a = way=20 to
decrease the rate of voltage rise just after the EC2 pulse ends=20 so
arcing in the A/B selection relay is suppressed. After the=20 relay
contacts open enough that an arc is no longer possible (which = shouldn't
take long) an open circuit condition now would allow the = injector=20 to
close quickly. The arcing may or may not be a problem any given = tim=20 Ed

-- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html
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