The AFRC uses one of seven possible methods to recognize if an engine is running. The available sensors to trigger the run signal are below.
- Auto-Detect (Default)
Scans all other run-signal sources for conditions indicating the engine is running
- AFRC Pre-Catalyst Thermocouple
AFRC Advanced terminals 48 and 49
AFRC Lite terminals 21 and 22
- AFRC Oil Pressure Switch
AFRC Advanced terminals 15 and 16
Oil Pressure Switch must be enabled on Sensor Setup – AI/DI (Pg. 202) screen of the AFRC Advanced
- AFRC RPM
AFRC Advanced terminals 17 and 18
RPM must be enabled and pulses per revolution must be defined on Sensor Setup – RPM (Pg. 205) screen of the AFRC Advanced
- EMD Pre-Catalyst Thermocouple
EMD terminals 24 and 25
- EMD Oil Pressure Switch
EMD terminals 39 and 40
Oil Pressure Switch must be enabled on Sensor Setup – AI/DI (Pg. 104) screen of the EMD
- Ignition State
Uses the current ignition state to determine run signal, if the ignition is in the “Engine Running” or “Engine Running With Warnings” state the run signal is set to running.
“Auto-Detect” will scan the other enabled “Trigger Sensor” inputs of the AFRC Advanced, AFRC Lite, EMD, and Ignition and toggle the engine run signal to “Run” if any of them indicate the engine is running.
If “Auto-Detect”, “AFRC Pre-Cat TC”, or “EMD Pre-Cat TC” is selected, a trigger temperature must also be configured. The trigger temperature defines the temperature at which the run signal will toggle. Any temperatures above the trigger will indicate the engine is running, and any temperatures below the trigger will indicate the engine is off. The default trigger temperature is 450°F.
Regardless of the selection on this screen, the ETS system will use “Auto-Detect” for the “Eng. Run” text on the top of pages, engine runtime hours, and alarm activation. The selection on the Run Signal Trigger page only effects when the AFRC considers the engine running. Note that if the AFRC pre-cat TC is the only sensor available, it will take time for the sensor to warm up enough for the EIM to display “Eng. Run”.