Vega EMS-1 Operating Manual
Page 7
3.2 EGT/CHT Trend Graph display
This display can be accessed by rotating the rotary control during the normal display mode. The trend graph displays the
last 160 seconds of EGT/CHT temperature readings.
3.3 Maximum Values display
This display can be accessed by rotating the rotary control during the normal display
mode. Press the F1/Up button when the max values display is showing to reset the
maximum values.
3.4 Engine leaning mode
EGT information is also very useful for fuel mixture control. As the fuel mixture is leaned,
so the exhaust gasses get hotter. This rise in temperature is a sign of increased
combustion efficiency as the optimum mixture setting is approached. If the leaning
progresses past a certain point however, the temperature will begin to drop. This
temperature drop is the result of reduced energy output from the diminished fuel flow.
The best operating mixture for aircraft engines is in the vicinity of this peak EGT reading.
The EMS-1 has a special Leaning mode, which easily identifies the peak EGT condition
allowing you to adjust your fuel mixture for best performance.
Fuel mixture should be adjusted once you have decided on a suitable cruise power
setting (typically 70%). Press the F1/Up button on the main display to enable the engine
leaning mode. The "LEAN" label is displayed at the top of the main display to clearly
differentiate it from the normal operating mode.
As the fuel mixture is slowly leaned past the point at which the temperature begins to
drop (by more than 10°C/15°F), the absolute EGT temperatures will change to show the
EGT reading relative to this peak. The sequential order as each cylinder peaks is also
shown.
Leaning mode can be canceled by pressing the F1/Up button again.
Note: The maximum values are stored in non-volatile
memory and are recalled on power-up.
