Return-Path: Sender: To: lml@lancaironline.net Date: Fri, 04 Nov 2005 13:24:17 -0500 Message-ID: X-Original-Return-Path: Received: from [24.93.47.42] (HELO ms-smtp-03-eri0.texas.rr.com) by logan.com (CommuniGate Pro SMTP 5.0) with ESMTP id 814228 for lml@lancaironline.net; Thu, 03 Nov 2005 21:10:12 -0500 Received-SPF: pass receiver=logan.com; client-ip=24.93.47.42; envelope-from=dryan@gt.rr.com Received: from [127.0.0.1] (cpe-70-115-0-30.gt.res.rr.com [70.115.0.30]) by ms-smtp-03-eri0.texas.rr.com (8.12.10/8.12.7) with ESMTP id jA429NRZ006917 for ; Thu, 3 Nov 2005 20:09:26 -0600 (CST) X-Original-Message-ID: <436AC2D6.9030206@gt.rr.com> X-Original-Date: Thu, 03 Nov 2005 20:09:26 -0600 From: Don Ryan User-Agent: Mozilla Thunderbird 1.0 (Windows/20041206) X-Accept-Language: en-us, en MIME-Version: 1.0 X-Original-To: Lancair Mailing List Subject: Re: [LML] Re: Lancair 320 gear problem -- help wanted References: In-Reply-To: Content-Type: multipart/alternative; boundary="------------090304070608050105000002" X-Virus-Scanned: Symantec AntiVirus Scan Engine This is a multi-part message in MIME format. --------------090304070608050105000002 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Scott: I think the main breaker only pulls power off of the relays through to the motor? I better check. I'm not sure that your pump tests emulate the sequence I probably experienced. First the down press switch would have opened, the gear down long enough for the press to build to open the switch. I would think that this is the more common state, unless there is a leak somewhere? Second the HP switch is activated, (the down circuit is not powered) and the up circuit is powered. What happens then when the down switch tries to reverse direction? Did your tests follow such a sequence? Sky2high@aol.com wrote: > In a message dated 11/2/2005 9:04:44 P.M. Central Standard Time, > marv@lancaironline.net writes: > Don, > > Do you mean the 50 amp motor CB? Was the relay power circuit (power > to the gear switch) source wired after the motor breaker? > I.E. Pulling the Motor power breaker also removes power from the relay > coil circuit? If so, what other changes from the Lancair wiring > diagram existed? > > BTW, I am asking these questions so that if we can find the cause, we > can hopefully prevent an event like this from ever occurring again. > > You asked about the bubbles - my test system is open and when it stops > running, air enters the clear tubing. when the pump starts I can see > which way the bubbles start going. After running a bit, the tube > representing the selected direction is completely full of flowing fluid. > > You must re-think the pressure switches again. If the pressure is > less than the desired end system pressure (up or down), then the > switch is closed to allow current,if present, to pass to the > associated relay coil. The only time any pressure switch is open is > when the final desired pressure is reached thus ensuring that relay > coil power is removed so that the pump stops running when the relay > opens. Of course there is a pressure band of perhaps 100-200 psi > below the target that the pressure switch remains open. So, once > again, if the pump is running, both pressure switches are CLOSED > because neither has reached the desired pressure. When the desired > pressure is reached, then the correct switch can OPEN to then open the > proper relay (remove coil power) and stop the motor from running. > > Scott Krueger AKA Grayhawk > Lancair N92EX IO320 SB 89/96 > Aurora, IL (KARR) > > > --------------090304070608050105000002 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Scott:
I think the main breaker only pulls power off of the relays through to the motor? I better check.
I'm not sure that your pump tests emulate the sequence I probably experienced.

First the down press switch would have opened, the gear down long enough for the press to build to open the switch. I would think that this is the more common state, unless there is a leak somewhere?

Second the HP switch is activated, (the down circuit is not powered) and the up circuit is powered.
What happens then when the down switch tries to reverse direction?

Did your tests follow such a sequence?

Sky2high@aol.com wrote:

In a message dated 11/2/2005 9:04:44 P.M. Central Standard Time, marv@lancaironline.net writes:

Don,

Do you mean the 50 amp motor CB? Was the relay power circuit (power to the gear switch) source wired after the motor breaker? I.E. Pulling the Motor power breaker also removes power from the relay coil circuit? If so, what other changes from the Lancair wiring diagram existed?

BTW, I am asking these questions so that if we can find the cause, we can hopefully prevent an event like this from ever occurring again.

You asked about the bubbles - my test system is open and when it stops running, air enters the clear tubing. when the pump starts I can see which way the bubbles start going. After running a bit, the tube representing the selected direction is completely full of flowing fluid.

You must re-think the pressure switches again. If the pressure is less than the desired end system pressure (up or down), then the switch is closed to allow current,if present, to pass to the associated relay coil. The only time any pressure switch is open is when the final desired pressure is reached thus ensuring that relay coil power is removed so that the pump stops running when the relay opens. Of course there is a pressure band of perhaps 100-200 psi below the target that the pressure switch remains open. So, once again, if the pump is running, both pressure switches are CLOSED because neither has reached the desired pressure. When the desired pressure is reached, then the correct switch can OPEN to then open the proper relay (remove coil power) and stop the motor from running.

Scott Krueger AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL (KARR)

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