Check Failsafe and Actuator Travel:
Set the signal-generator frequency to about half of idle speed. Set the idlerated switch to rated. Turn the signal generator and governor power on. The
linkage must be at the maximum-fuel position. Except for Detroit Diesel
engines, verify that linkage travel is limited by the prime-mover fuel control,
not by the actuator stop. Turn the signal generator off and remove the
connections at terminals 5 and 6. The linkage should move to the minimum
fuel position. Verify that linkage travel is limited by the prime mover’s fuel
control, not by the actuator stop.
Preset Rated Speed:
Set the signal generator for MPU frequency at rated speed and connect it to
terminals 5 and 6. Put the idle-rated switch in the rated position. Set the
speed trim pot, if connected, to mid-position. Observe the linkage position.
If the linkage Is at the maximum fuel position:
Slowly turn the rated speed pot counterclockwise until the linkage just
begins to move to the minimum fuel position. Start Fuel (if present) must be
adjusted to the maximum clockwise position or the actuator will not move to
maximum.
If the linkage Is at the minimum fuel position:
Slowly turn the rated speed pot clockwise until the linkage just begins to
move to the maximum fuel position.
Continue to adjust the rated speed pot very slowly in the appropriate
direction, trying to stop the linkage between the minimum and maximum fuel
stops. Because it is not possible to stop the motion, cease adjusting when
the linkage moves slowly. The rated speed reference is now set very close
to desired speed. A slight adjustment when the engine is running will
achieve the exact speed.
Preset Idle Speed:
Preset idle speed only after presetting rated speed. Set the signal generator
for the MPU frequency at idle speed. Put the idle-rated switch in the idle
position. Observe the linkage position.
If the linkage is at the maximum fuel position:
Slowly turn the idle speed pot counterclockwise until the linkage just begins
to move to the minimum fuel position. Start Fuel (if present) must be
adjusted to the maximum clockwise position or the actuator will not move to
maximum.
If the linkage is at the minimum fuel position:
Slowly turn the idle speed pot clockwise until the linkage just begins to move
to the maximum fuel position.
Continue to adjust the idle speed pot very slowly in the appropriate direction,
trying to stop the linkage between the minimum and maximum fuel stops.
Because it is not possible to stop the motion, cease adjusting when the
linkage moves slowly. The idle speed reference is now set very close to
desired speed. A slight adjustment when the engine is running will achieve
the exact speed.
