X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Tue, 26 Nov 2013 13:27:59 -0500 Message-ID: X-Original-Return-Path: Received: from rc1-smtp.comporium.net ([208.104.2.18] verified) by logan.com (CommuniGate Pro SMTP 6.0.7) with ESMTP id 6615185 for lml@lancaironline.net; Tue, 26 Nov 2013 11:51:59 -0500 Received-SPF: pass receiver=logan.com; client-ip=208.104.2.18; envelope-from=snopercod@comporium.net Received: from rg20.comporium.net ([208.104.244.60]) by rc1-smtp.comporium.net ({6ef86d1c-fcb7-4b71-ab61-5707d6041926}) via TCP (outbound) with ESMTP id 20131126165125233; Tue, 26 Nov 2013 16:51:25 +0000 X-RC-FROM: Received: from 33.225.235.68.dsl.brvdnc.dynamic.citcom.Net (EHLO _127.0.0.1_) ([68.235.225.33]) by rg20.comporium.net (MOS 4.3.4-GA FastPath queued) with ESMTP id CFN48744 (AUTH snopercod); Tue, 26 Nov 2013 11:51:24 -0500 (EST) X-Original-Message-ID: <5294D189.6010105@comporium.net> X-Original-Date: Tue, 26 Nov 2013 11:51:21 -0500 From: John Cooper User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.1.1 MIME-Version: 1.0 X-Original-To: lml@lancaironline.net, Colyn Case Subject: Re: A couple Tyco papers on emf reduction in relays Content-Type: multipart/alternative; boundary="------------020502070705040208050700" X-MAG-OUTBOUND: comporium.redcondor.net@208.104.244.48/28 This is a multi-part message in MIME format. --------------020502070705040208050700 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Colyn-- Those Tyco links were excellent, thanks. Let's keep in mind, though, that Tyco was discussing the possible adverse effects of surge protection across the relay _coils_, not the _contacts_. Based upon the information in those articles I'm going to remove the small ZNRs I installed across my hydraulic relay coils to protect the landing gear switch contacts. Perhaps I'll replace them with those Snapjacks (Thanks for that link as well.) I plan to leave the large ZNRs in placed across the hydraulic relay_contacts_. Those Tyco articles may be of special interest to Adam since his Bosch 0 332 002 156 hydraulic relays have the built-in diode protection across the coils. Also, the second article discussed how excessive inrush can cause relay failure. FWIW, I ordered a 60A shunt which will (hopefully) allow me to measure the inrush current on the Oildyne pump motor. I'll report back if I learn anything. --------------020502070705040208050700 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Colyn--

Those Tyco links were excellent, thanks. Let's keep in mind, though, that Tyco was discussing the possible adverse effects of surge protection across the relay coils, not the contacts. Based upon the information in those articles I'm going to remove the small ZNRs I installed across my hydraulic relay coils to protect the landing gear switch contacts. Perhaps I'll replace them with those Snapjacks (Thanks for that link as well.) I plan to leave the large ZNRs in placed across the hydraulic relay contacts.

Those Tyco articles may be of special interest to Adam since his Bosch 0 332 002 156 hydraulic relays have the built-in diode protection across the coils. Also, the second article discussed how excessive inrush can cause relay failure.

FWIW, I ordered a 60A shunt which will (hopefully) allow me to measure the inrush current on the Oildyne pump motor. I'll report back if I learn anything.
--------------020502070705040208050700--