X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from smtp2go.com ([207.58.142.213] verified) by logan.com (CommuniGate Pro SMTP 5.4.1) with ESMTPS id 5124506 for flyrotary@lancaironline.net; Wed, 14 Sep 2011 13:54:01 -0400 Received-SPF: none receiver=logan.com; client-ip=207.58.142.213; envelope-from=crobinson@medialantern.com Message-ID: <4E70EA14.3090602@medialantern.com> Date: Wed, 14 Sep 2011 13:53:24 -0400 From: Chad Robinson User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.1) Gecko/20110830 Thunderbird/6.0.1 MIME-Version: 1.0 To: Rotary motors in aircraft CC: Al Wick Subject: Re: [FlyRotary] Re: The good news and the bad news...... References: In-Reply-To: Content-Type: multipart/alternative; boundary="------------090604070607070600010302" This is a multi-part message in MIME format. --------------090604070607070600010302 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit On 9/14/2011 1:48 PM, Al Wick wrote: > If memory serves, it's 0 to 5vdc square wave. > Yes, but I'm not sure where you are going. You thinking normally > closed contacts to OEM CAS, norm open to backup CAS? You still have to > manage angle offset. Would be unfortunate to have moisture in relay or > turbulence disrupt CAS. Likely not going to end up with safety > improvement. Good creative idea though. The rotary engine CAS is set up on a bracket near the front pulley. I was envisioning a system where you had a sensor in exactly the same spot on the other side of the toothed wheel. You might need an offset alternator pulley to make room for it - but then you don't have to worry about angles/offsets. It's just a second sensor, ready to go - flip a switch and try an engine restart. If relay reliability was a concern there are always SSRs or even just good switching transistors... --------------090604070607070600010302 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit On 9/14/2011 1:48 PM, Al Wick wrote:
<What kind of signal is on the CAS line
If memory serves, it's 0 to 5vdc square wave.
 
<Could it go through a relay safely?
Yes, but I'm not sure where you are going. You thinking normally closed contacts to OEM CAS, norm open to backup CAS? You still have to manage angle offset. Would be unfortunate to have moisture in relay or turbulence disrupt CAS. Likely not going to end up with safety improvement. Good creative idea though.
The rotary engine CAS is set up on a bracket near the front pulley. I was envisioning a system where you had a sensor in exactly the same spot on the other side of the toothed wheel. You might need an offset alternator pulley to make room for it - but then you don't have to worry about angles/offsets. It's just a second sensor, ready to go - flip a switch and try an engine restart. If relay reliability was a concern there are always SSRs or even just good switching transistors...

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