Hello All,

I have a dumb ass question for those of you with am EMS system (GRT, Dynon, JPI)

What is the benefit of a "Span Alarm"?  I mean I understand the theory of what it monitors- the temperature difference of either EGT or CHT between cylinders.  But what is the application of this information in a "real word" setting?

Knowing that jug #3 is 25 degrees hotter than jug #2 would indicate that I take what action? Or is it more of an informational tidbit that would be the harbinger of a jug that's about to depart the aircraft or some other combustion catastrophe?

I understand the shock cooling feature-if there is a change in temp that exceeds 50 degrees F/minute, I can add power, I can slow my descent, etc

Your Thoughts?

Brad Cohen

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It might be useful to detect detonation which would cause a rapid temperature increase in the effected cylinder(s). 




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