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Mark Spickard
07-24-2018, 05:35 AM
On a very long cross country the Hobbs time didn't seem to agree with my watch or GNS430 timer. While in cruise flight, the elapsed time (about two hours) of the AF-2500 is off by about 12-13%.....it shows less time than actual. It also seems to be a bit variable.....about 12% for one test, about 13% for another test on another day. Does AFS know what would cause this, if it could be variable, if it likely existed since the unit was new? I have used this timer for all log book entries (flight and maintenance) over the last 1100 hours or so......not good.

Shawn McGinnis
07-30-2018, 03:12 PM
Are you getting stable RPM readings? For the AF-2500, tach time is hours on engine above 1250 RPM. Hobbs Time is hours on engine above 0 RPM.

Mark Spickard
07-31-2018, 08:52 AM
Are you getting stable RPM readings? For the AF-2500, tach time is hours on engine above 1250 RPM. Hobbs Time is hours on engine above 0 RPM.

RPM is stable. While in continuous cruise flight, the elapsed tach and hobbs time are the same....and both in error. The clock is always correct. I have dual lightspeed ignition and I have the electronic adapter box you guys provide to get rpm signal from the lightspeed to the analog unit.

Shawn McGinnis
08-01-2018, 09:40 AM
I'm not seeing any notes with time accumulation issues. Can you check which version of software your AF-2500 is running using the TIME button?

Mark Spickard
08-08-2018, 09:44 AM
Version 3.2.2 A04

Shawn McGinnis
08-16-2018, 11:28 AM
I don't see any software updates that make changes to this portion of the AF-2500 code. You probably have a hardware issue in the display. Call Tricia at 503-263-0037 x 2 and she can set up an RMA for diagnosis.