Dynon Avionics EMS-D120 Pilots Users Guide - Manual (Page 30)

EMS Monitoring Functions
6-2 EMS-D120 Pilot’s User Guide
To exit the Lean mode, reactivate the main menu and press the LEAN button; the EGT/CHT display then returns to its
normal state.
For best results, lean carefully by making small adjustments and allowing some time for temperatures to stabilize before
leaning further. In addition to the EGT temperatures, you can also watch the fuel flow rate and CHT temperatures.
Carefully read and follow your engine manufacturer’s leaning recommendations for best performance.
On some engines, when given the proper set of inputs, the EMS can also calculate percent power and lean-of-peak or
rich-of-peak operation in real time. To do this, the EMS needs access to OAT, MAP, RPM, Altitude (from EFIS or GPS)
and fuel flow, and be used on a normally aspirated engine that is close in performance to a “stock”
Lycoming/Continental engine. This information is based on Lycoming and Continental power charts, is updated in real
time, and is displayed near the manifold pressure gauge. The leaning information has three states, LOP, ROP, and PK
(Peak). This information can be used to determine when it is safe to lean the engine, and if the current operating state is
near peak or not. While this information is based on published charts, you should independently verify via manual
leaning that this data matches your install and engine.
Data Logging
While many observations can be made via the various indicators on the EMS Main Page, some patterns are too subtle to
be noticed during routine flight. Automatically recording (“logging”) engine monitor data over longer periods of
operation allows you to spot potential problems before they cause costly damage or result in a flight emergency. The
EMS-D120 provides two options for logging data. You may configure the EMS-D120 to log data to its internal memory
for later retrieval or you may record streaming data serial output to an external device (such as a laptop computer) in
real-time from the serial port. The former option is has the advantage that it does not require a laptop or other data
logging device in the aircraft while recording. Additionally, the internal storage logs alarm events, while the real-time
output does not. When data logging is activated, two logs are recorded - “all data” and “MIN/MAX”. Both logs can be
downloaded using the “Retrieve Logged Data” option of the Dynon Support Program. On certain Dynon Avionics EFIS