X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 08 May 2012 07:51:23 -0400 Message-ID: X-Original-Return-Path: Received: from elasmtp-galgo.atl.sa.earthlink.net ([209.86.89.61] verified) by logan.com (CommuniGate Pro SMTP 5.4.5) with ESMTP id 5526818 for lml@lancaironline.net; Mon, 07 May 2012 21:13:14 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.61; envelope-from=colyncase@earthlink.net DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=dk20050327; d=earthlink.net; b=MQWCnsNqPe/ZYAyeEGnxXnxr/wUdwS6MvOXJ7ezomHMD2o0Q0WQWBlGOQk7ZsL56; h=Received:From:Mime-Version:Content-Type:Subject:Date:In-Reply-To:To:References:Message-Id:X-Mailer:X-ELNK-Trace:X-Originating-IP; Received: from [70.16.68.225] (helo=[192.168.1.24]) by elasmtp-galgo.atl.sa.earthlink.net with esmtpa (Exim 4.67) (envelope-from ) id 1SRYym-00033P-6M for lml@lancaironline.net; Mon, 07 May 2012 21:12:40 -0400 From: Colyn Case Mime-Version: 1.0 (Apple Message framework v1084) Content-Type: multipart/alternative; boundary=Apple-Mail-120--497409433 Subject: Re: [LML] Contactor test X-Original-Date: Mon, 7 May 2012 21:12:39 -0400 In-Reply-To: X-Original-To: "Lancair Mailing List" References: X-Original-Message-Id: X-Mailer: Apple Mail (2.1084) X-ELNK-Trace: 63d5d3452847f8b1d6dd28457998182d7e972de0d01da9408bad16906e87f2bf60c27319657ca950350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 70.16.68.225 --Apple-Mail-120--497409433 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=windows-1252 My issues with the stock contactors: 1) mechanically not very impressive. The can is held on by some little = legs that are bent into place. One of mine fell apart because of an = installation error that put mechanical stress on the package. =20 2) hold current of the coil is high 3) I don't know what their rated max break current is (maybe just my = fault for not being a better sleuth). One of my concerns was being = able to interrupt a high current circuit before something melted (e.g. = starter or master or hydraulic pump) On May 7, 2012, at 7:51 AM, Bill Wade wrote: I took Paul Miller=92s suggestion and tested the windings on the 50A = Leach and the Lancair- supplied contactors. =20 I connected a 24V power supply to the coil terminals without any load = across the points and after 36 hours continuous the Leach case was = slightly warm to the touch. All of the terminals checked out- = electrically isolated from the case, low resistance across the points. =20 The Lancair contactor was very different. Within about 15 minutes the = case was too hot to hold comfortably. The winding and contact terminals = grounded to the case in an apparently random fashion with changing = values of resistance and voltage. When the unit cooled down the = terminals were electrically isolated and coil resistance was as new so = the coil wasn=92t shorted internally and the unit seemed to be fine. As = power was reapplied and the coil began to warm the process repeated. =20 I haven=92t heard of any problems on the LML so these contactors seem = to be adequate for the job. Oildyne says the pump is intermittent duty = (no percentage given) so it might be toasted before any problem with the = contactor showed up. OTOH the contactor is relatively heavy and seems = marginal- people using them might consider something different. =96Bill Wade --Apple-Mail-120--497409433 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=windows-1252 My = issues with the stock contactors:
1) mechanically not very = impressive.  The can is held on by some little legs that are bent = into place.  One of mine fell apart because of an installation = error that put mechanical stress on the package. =   
2) hold current of the coil is high
3) = I don't know what their rated max break current is (maybe just my fault = for not being a better sleuth).   One of my concerns was being able = to interrupt a high current circuit before something melted (e.g. = starter or master or hydraulic pump)

On May 7, = 2012, at 7:51 AM, Bill Wade wrote:

  I took Paul Miller=92s suggestion and tested the windings on = the 50A=20 Leach and the Lancair- supplied contactors.
 
  I connected a 24V power supply to the coil terminals without = any=20 load across the points and after 36 hours continuous the Leach case was = slightly=20 warm to the touch. All of the terminals checked out- electrically = isolated from=20 the case, low resistance across the points.
 
  The Lancair contactor was very different. Within about 15 = minutes=20 the case was too hot to hold comfortably. The winding and contact = terminals=20 grounded to the case in an apparently random fashion with changing = values of=20 resistance and voltage. When the unit cooled down the terminals were=20 electrically isolated and coil resistance was as new so the coil wasn=92t = shorted=20 internally and the unit seemed to be fine. As power was reapplied and = the coil=20 began to warm the process repeated.
 
  I haven=92t heard of any problems on the LML so these = contactors seem=20 to be adequate for the job. Oildyne says the pump is intermittent duty = (no=20 percentage given) so it might be toasted before any problem with the = contactor=20 showed up. OTOH the contactor is relatively heavy and seems marginal- = people=20 using them might consider something different.
    =96Bill Wade

= --Apple-Mail-120--497409433--