X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 26 May 2009 16:22:00 -0400 Message-ID: X-Original-Return-Path: Received: from rg4.comporium.net ([208.104.2.24] verified) by logan.com (CommuniGate Pro SMTP 5.2.14) with ESMTPS id 3652342 for lml@lancaironline.net; Sun, 24 May 2009 17:13:05 -0400 Received-SPF: pass receiver=logan.com; client-ip=208.104.2.24; envelope-from=snopercod@citcom.net Received: from 194.112.58.67.dsl.brvdnc.dynamic.citcom.Net (EHLO _67.58.112.194_) ([67.58.112.194]) by rg4.comporium.net (MOS 3.8.4-GA FastPath queued) with ESMTP id BPM38545 (AUTH snopercod); Sun, 24 May 2009 17:12:27 -0400 (EDT) X-Original-Message-ID: <4A19B83D.9020003@citcom.net> X-Original-Date: Sun, 24 May 2009 17:12:29 -0400 From: John Cooper User-Agent: Thunderbird 2.0.0.21 (Windows/20090302) MIME-Version: 1.0 X-Original-To: lml@lancaironline.net Subject: Re: Gear Relays are not working Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Junkmail-Status: score=10/70, host=rg4.comporium.net X-Junkmail-SD-Raw: score=unknown, refid=str=0001.0A010207.4A19B83B.00EC,ss=1,fgs=0, ip=67.58.112.194, so=2007-03-13 10:31:19, dmn=5.7.1/2008-09-02 Good comments so far by several responders. My personal additions: 1. A 50A circuit breaker specified in the plans will in no way protect your hydraulic pump from burning up should the rotor lock up, neither will it protect your #10 pump wiring from burning up in the event of a fault. This error by the factory dates back to the very first kit in 1986(?), and AFAIK, Lancair has never corrected it. The Oildyne pump draws maybe ~15 Amps when the gear are in motion, which spikes up to ~30 Amps just before the pressure switch stops the pump. A 50 Amp circuit breaker will take roughly 3 minutes to trip with 100 Amps flowing through it. Think about that. If you insist on using a circuit breaker, 30A would be better, but still won't protect you from smoke in the cockpit should your pump lock up. (A 30A or 40A Maxi-Fuse offers better protection.) 2. Yes, connect the control power circuit breaker downstream of the main circuit breaker for the hydraulic pump. That way, the relays can't stay energized when the main CB (or fuse) is open. 3. I recommend high-reliability 75A Bosch Relays for the hydraulic pump, not the crap that the factory provided. (see details and part numbers posted here sometime during the last year). 4. Yes, use the back-to-back diodes to feed your "gear transition light". (See the schematic I posted here a few months ago). I used a red/green LED which shows red when the hydraulic pump is running in either direction, and green when the nose gear door is closed. 5. Lance was a true genius when it came to aerodynamics, aesthetics, and business, but he didn't know diddly about electricity.