Guy Buchanan
Joined: 16 Jul 2006 Posts: 1204 Location: Ramona, CA
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Posted: Wed Sep 16, 2020 8:48 pm Post subject: Rotax 912 Eating Ignition Modules |
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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
gebuchanan(at)cox.net
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Description: |
Rotax Ignition Module Ground Wire, Ground "grounded". |
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197.99 KB |
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1085 Time(s) |
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Description: |
Rotax Ignition Module Ground Wire, Ground "open". |
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Filesize: |
213.21 KB |
Viewed: |
1085 Time(s) |
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_________________ Guy Buchanan
Deceased K-IV 1200
A glider pilot too. |
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