9905-003 WOODWARD

Low speed is not 

regulated by LOW 

IDLE SPEED 

potentiometer. 

NOTE 

On carbureted prime movers, the 

minimum fuel stop rpm setting will 

vary with prime mover 

temperature. An improper cold 

setting may interfere with the Low 

Idle Speed Setting when the prime 

mover is hot. 

The Low Idle Speed setting may be below the minfuel position of the actuator or prime-mover fuel 

stop. In this case, the output voltage to the actuator 

will be zero (maximum for reverse acting controls). 

The engine will be maintained at the min-fuel 

position by the actuator or the prime mover min-fuel 

stop. The conditions indicate that the min-fuel 

position should be decreased by linkage 

adjustment (diesel) or low-idle set screw (gas 

engine), or the LOW IDLE SPEED setting should 

be raised. If this does not correct the problem, the 

2301A control may be faulty. 

LOW IDLE SPEED potentiometer. If adjustment of the LOW IDLE SPEED 

potentiometer causes erratic behavior, replace the 

control. 

Prime mover does 

not decelerate when 

Close for Rated 

contact is open. 

Faulty Close for Rated contact or 

wiring. 

The voltage from terminal 5 (–) to 2 (+) on low 

voltage controls or 5 (–) to 6 (+) on high voltage 

controls must be less than 2 volts. Replace the 

contact or wiring as necessary. 

LOW IDLE SPEED set fully cw 

(be careful not to overtorque 

the pot). 

Turn LOW IDLE SPEED setting ccw with terminal 5 

open. 

2301A ramp circuitry. 

WARNING 

The speed-setting controls 

have sufficient range to 

override the ramp and bring the 

prime-mover speed up to rated 

while still in the low-idle mode 

(because of control or 

switching defect). A Close for 

Rated contact that is 

intermittent may cause the 

prime mover to overspeed if the 

RATED SPEED setting is 

adjusted for rated speed with 

terminal 5 open.

A faulty Close for Rated contact may remain in the 

accelerate position with the contact open. 

If the Close for Rated contact is operative, loss of 

idle control may be due to a faulty circuit. 

In general, adjustment of LOW IDLE SPEED will 

vary the speed of the prime mover with the Close 

for Rated contact in the decelerate (open) position. 

Adjustment of LOW IDLE SPEED should not affect 

prime mover speed when the Close of Rated 

contact is closed. 

Prime mover will not 

stabilize at rated noload speed. The 

instability may occur 

at no load or it may 

vary with load. 

Control may be 

erratic. 

2301A Speed Control. Adjust GAIN, RESET, and ACTUATOR 

COMPENSATION as described in "Adjust for 

Stable Operation" and "Dynamic Adjustment" in 

Chapter 3. 

Speed setting controls. If adjustment of external speed trim causes 

instability, check potentiometer with ohmmeter for 

erratic behavior. (Turn power off). Use nonlubricating electrical cleaner if necessary. If internal 

potentiometer is faulty, replace control. 

Improper linkage adjustment. Make sure the actuator moves about 2/3 of its 

travel from no load to full load. Be sure linkage 

provides a proportional change in power for every 

change in actuator terminal-shaft position. Refer to 

the actuator manual for more detailed linkage 

instructions. 

Necessary wires not properly 

shielded. 

Electrical noise, caused by wiring carrying an ac 

voltage or stray magnetic fields, can be picked up 

by improperly shielded wire. 

Noise will cause instability. See "Shielding" in 

Chapter 3.