Preset rated speed.
If a signal generator is not used, set the RATED SPEED potentiometer at
minimum (fully counterclockwise).
If a signal generator is used set the signal for the frequency of the speed
sensor at rated speed, and connect it to terminals 7 and 8. (The rated speed
frequency in Hz equals the rated engine speed in RPM times the number of
teeth on the speed sensing gear, times the ratio of engine speed to speedsensing-gear speed, divided by 60.) Put the Close For Rated contact in
rated (closed) position. Set the speed trim potentiometer (if used) to midposition. Connect a dc analog voltmeter to terminals 9 (+) and 10 (–) to read
actuator voltage.
If the actuator voltage is at minimum (about 0 volts) slowly turn the RATED
SPEED potentiometer clockwise (counterclockwise for reverse acting
controls) until the voltage just begins to move toward maximum.
If the actuator voltage is at maximum, slowly turn the RATED SPEED
potentiometer counterclockwise (clockwise for reverse-acting controls) until
the voltage just begins to move toward minimum.
Continue to very slowly adjust the RATED SPEED potentiometer in the
appropriate direction, trying to stop the actuator voltage between the
minimum and maximum voltages. Because it is not possible to stop the
motion, cease adjusting when the voltage changes very slowly. The RATED
SPEED potentiometer is now set very close to the desired speed. A slight
adjustment when the engine is running will achieve the exact speed.
