---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Fri 09/18/20: 2 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:20 PM - Rotax 912 Eating Ignition Modules (Guy Buchanan) 2. 07:27 PM - Re: Rotax 912 Eating Ignition Modules (william sullivan) ________________________________ Message 1 _____________________________________ Time: 07:20:05 PM PST US Subject: RotaxEngines-List: Rotax 912 Eating Ignition Modules From: "Guy Buchanan" A friend has a 912uls in a Kitfox that seems to be eating ignition modules. He's gone through three. Yes they were all old. Yes new ones work, but we're worried that maybe his plane is producing electrical noise detrimental to the modules. We did some testing using an oscilloscope looking for voltage spikes in the ground wire during start up and shutoff. For various reasons we weren't able to capture any voltage spikes during start and stop, but did capture some very messy noise signatures while running. Picture 1 shows one module's ground wire while "open". Note +/- 30V peaks and a regular 30hz sawtooth. Picture 2 shows the same ground "grounded". We did some further testing of the input and output to the voltage regulator and those voltages appeared relatively clean. Question: is it possible the ignition module is being damaged by the voltage noise, regardless of source? Should we apply some caps to the ground wires to kill the noise? Thanks, -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=498422#498422 Attachments: http://forums.matronics.com//files/labnation_screenshot2_112.png http://forums.matronics.com//files/labnation_screenshot0_140.png ________________________________ Message 2 _____________________________________ Time: 07:27:33 PM PST US From: william sullivan Subject: Re: RotaxEngines-List: Rotax 912 Eating Ignition Modules My gut instinct says clean and tighten all grounds. If a component grounds through it's base, take off the unit and clean and ground the contact area . Good luck! Bill Sullivan On Friday, September 18, 2020, 10:21:35 PM EDT, Guy Buchanan wrote: t> A friend has a 912uls in a Kitfox that seems to be eating ignition modules. He's gone through three. Yes they were all old. Yes new ones work, but we' re worried that maybe his plane is producing electrical noise detrimental t o the modules. We did some testing using an oscilloscope looking for voltag e spikes in the ground wire during start up and shutoff. For various reason s we weren't able to capture any voltage spikes during start and stop, but did capture some very messy noise signatures while running. Picture 1 shows one module's ground wire while "open". Note +/- 30V peaks and a regular 30 hz sawtooth. Picture 2 shows the same ground "grounded". We did some furthe r testing of the input and output to the voltage regulator and those voltag es appeared relatively clean. Question: is it possible the ignition module is being damaged by the voltage noise, regardless of source? Should we appl y some caps to the ground wires to kill the noise? Thanks, -------- Guy Buchanan K-IV 1200 / 912Uls / Warp / 500 hours and flying again. Now a glider pilot too. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=498422#498422 Attachments: http://forums.matronics.com//files/labnation_screenshot2_112.png http://forums.matronics.com//files/labnation_screenshot0_140.png - S - WIKI - - =C2- =C2- =C2- =C2- =C2- -Matt Dralle, List Admin. ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.