Chapter 5.
System Troubleshooting Charts
Problem Cause Remedy
Prime mover will not start. Actuator not moving to start fuel position.
Supply voltage polarity reversed, or no supply voltage.
Check for supply voltage from terminals 24 (+) to 25 (–). Reverse leads if polarity is incorrect.
If the actuator moves to start position, a problem with the prime mover fuel supply is indicated.
Actuator not responding to input
signal from control.
If there is a voltage output at control terminals 1 (+)
and 2 (–), but the actuator does not move, check
the wiring to the actuator for opens or shorts.
Check the polarity of the actuator and feedback.
Check actuator and linkage for proper installation
and operation. Problems may be direction of
rotation, linkage, worn components, or improper
adjustment.
Start fuel limit set too low. Increase start fuel limit until prime mover starts.
Increase Start Ramp.
Speed setting too low on initial
start.
Speed setting may be lower than cranking speed.
Control should be set for rated speed. Increase
Rated Speed setting.
If adjusting Rated Speed does not produce the
correct output, return Rated Speed setting to
normal start position.
Idle Speed setting may be set
too low.
Adjust idle speed.
Run/Stop contact open. Check terminal 23. Run/Stop contact must be
closed for normal operation. Check monitor menu
for switch position.
Manual 04121 ProAct I/II
Woodward 53
Problem Cause Remedy
Prime mover will not
start. Actuator not
moving to start fuel
position. (cont.)
Speed sensor signal not
clearing failed speed signal
circuit.
Check wiring for proper connection. Check shields
for proper installation.
Speed sensor not spaced properly. Check for at
least 1.0 Vac at terminals 10 and 11 during
cranking. If less than 1.0 Vac, magnetic pickup may
be spaced too far from gear. Make sure there are
no metal chips on end of pickup.
Check the number of teeth seen by the MPU per
engine revolution against the number entered in
step 2 of Menu 6.
If no voltage is present, magnetic pickup may be
open-circuited or shorted. Make resistance check
with the leads disconnected from control. Should be
100 to 300 .
Check Error Menu 0 for faults.
The Failed Speed Signal must be enabled for
routine operation of the engine to ensure
shutdown and prevent possible life threatening
overspeed should the MPU signal be lost at
some future time.
Check Monitor Menu for Speed When Cranking.
Be prepared to make an emergency shutdown
when starting the engine, turbine, or other type
of prime mover, to protect against runaway or
overspeed with possible personal injury, loss of
life, or property damage.
Faulty ProAct control. Replace control.
ProAct I/II Manual 04121
54 Woodward
Problem Cause Remedy
Prime mover
overspeeds only on
starts.
Control adjustment. Control may be adjusted for sluggish operation
causing overspeed on start. Slowly adjust GAIN for
fastest stable response. Stability may be adjusted
too low. Increase Stability setting.
Start Fuel Limit may be too high.
Start Ramp may be too high.
Start speed may be too low.
Wrong set of dynamics may have been selected.
Linkage/Coupling. On diesel installations verify that fuel rack is not
binding and linkage is properly adjusted. It may be
necessary to determine if the fuel rack is quickly
following the actuator.
On carburetor installations check that the butterfly is
not binding.
Check linkage or coupling adjustment.
Overspeed Device. Verify proper operation of overspeed protection
devices to determine if a shutdown is occurring
without an overspeed condition.
ProAct control. If the control does not cut back the actuator output
(Menu 5), the ProAct control may be faulty. If the
signal is cut back, look for a problem in the linkage
or actuator.
Prime mover
overspeeds after
operating at rated
speed for some time.
Prime mover. Check for proper operation of prime mover fuel
system. If actuator moves toward minimum fuel
during overspeed, problem may not be connected
with the governor.
Speed not regulated
(hunting).
Incorrect dynamics
programmed in control or
incorrect dynamics program
selected.
Improve dynamics settings or select correct
dynamics program.
Los speed is not
regulated at idle
speed.
Actuator and linkage. The Idle Speed setting may be below the minimumfuel
position of the actuator or prime mover fuel
stop. In this case, the output voltage to the actuator
will be zero.
The engine will be maintained at the minimum-fuel
position by the actuator or the prime mover
minimum-fuel stop. These conditions indicate that
the prime mover minimum-fuel position should be
decreased by linkage adjustment (diesel engine) or
low-idle set screw (gas engine), or the Idle Speed
setting should be raised. If this action does not
correct the problem, the control may be faulty.
Prime mover does not
decelerate when
Rated contact is open.
Faulty Rated contact. Check Idle/Rated contact. Remove wire from
terminal 17. Prime mover should decelerate.
ProAct control ramp circuitry. A faulty Rated contact may remain in the accelerate
position with the contact open.
If the Rated contact is operative, loss of idle control
may be due to a faulty circuit.
Manual 04121 ProAct I/II
Woodward 55
Problem Cause Remedy
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.
ProAct control. Adjust GAIN, Stability, and ACTUATOR
COMPENSATION in Menu 1 or 2. Check Gain
Breakpoint for the lower speeds.
Necessary external wires not
properly shielded. (Electrical
noise, caused by wiring carrying
an ac voltage, stray magnetic
fields from transformers, etc.,
can be picked up by improperly
shielded wire. Noise will cause
instability if picked up by
magnetic pickup, position
feedback, auxiliary input, or
remote reference lines.)
The following tests will isolate noise and
interference.
Verify that the switchgear frame, governor chassis,
and prime mover have a common ground
connection. Temporarily remove the battery-charger
cables from the control battery system.
If the prime-mover operation is significantly
improved by these modifications, replace the wires
one at a time to locate the source of the trouble.
External wiring may require additional shielding or
rerouting from high-current lines or components.
If the problem cannot be solved by these checks, it
will be necessary to remove the control from the
switchgear. Temporarily mount the control next to
the prime mover and connect only a battery,
magnetic pickup, and actuator to the control (use a
separate battery placed next to the prime mover).
After starting the prime mover, if necessary, apply
load to check stability.
If stability occurs when the control is mounted next
to the prime mover, return the control to the
switchgear. Run new magnetic pickup, actuator
feedback, and battery power lines. Shield all wires
to the control. Route all wires through conduit or an
outer shield. Tie the outer shield to system ground
at the end opposite to the control.
Prime mover may not be
receiving fuel as called for by
the actuator voltage.
Check actuator linkage to fuel-controlling
mechanism for any lost motion, binding, or
excessive loading. Verify a steady fuel pressure of
proper value.
Prime mover not operating
properly.
Prime mover may be causing speed variations.
Control engine manually to determine if instability is
in prime mover or governor control. Verify proper
adjustment of fuel control linkage.
Input voltage low. Check supply voltage. It should be at least 18 Vdc,
not more than 32 Vdc.
Prime mover will not
accept full load.
Prime mover. If droop occurs near the full-load point only, it is
possible the prime mover is not producing the
power called for by the fuel control, or is being
overloaded. Either is indicated if the fuel control is at
maximum position.
ProAct control. Check Max Fuel Limit setting. Increase if required.
Check Torque Limiter settings. Increase if required.
Check droop setting. Set to 0 if required.
Check Aux Input terminals to see if the auxiliaries
are out of range. Maximum voltage is 2.5 Vdc.
Check linkage from actuator to fuel rack.