Woodward 2301A User manual

Installation and Operation Manual
2301A
Load Sharing and Speed Control
9900-430, 9900-431, 9900-432, 9900-433
Manual 02303

WARNING—DANGER OF DEATH OR PERSONAL INJURY
WARNING—FOLLOW INSTRUCTIONS
Read this entire manual and all other publications pertaining to the work to be performed
before installing, operating, or servicing this equipment. Practice all plant and safety
instructions and precautions. Failure to follow instructions can cause personal injury and/or
property damage.
WARNING—OUT-OF-DATE PUBLICATION
This publication may have been revised or updated since this copy was produced. To verify
that you have the latest revision, be sure to check the Woodward website:
www.woodward.com/pubs/current.pdf
The revision level is shown at the bottom of the front cover after the publication number. The
latest version of most publications is available at:
www.woodward.com/publications
If your publication is not there, please contact your customer service representative to get
the latest copy.
WARNING—OVERSPEED PROTECTION
The engine, turbine, or other type of prime mover should be equipped with an overspeed
shutdown device to protect against runaway or damage to the prime mover with possible
personal injury, loss of life, or property damage.
The overspeed shutdown device must be totally independent of the prime mover control
system. An overtemperature or overpressure shutdown device may also be needed for
safety, as appropriate.
WARNING—PROPER USE
Any unauthorized modifications to or use of this equipment outside its specified
mechanical, electrical, or other operating limits may cause personal injury and/or property
damage, including damage to the equipment. Any such unauthorized modifications: (i)
constitute "misuse" and/or "negligence" within the meaning of the product warranty
thereby excluding warranty coverage for any resulting damage, and (ii) invalidate product
certifications or listings.
CAUTION—POSSIBLE DAMAGE TO EQUIPMENT OR PROPERTY
CAUTION—BATTERY CHARGING
To prevent damage to a control system that uses an alternator or battery-charging device, make
sure the charging device is turned off before disconnecting the battery from the system.
CAUTION—ELECTROSTATIC DISCHARGE
Electronic controls contain static-sensitive parts. Observe the following precautions to
prevent damage to these parts.
• Discharge body static before handling the control (with power to the control turned off,
contact a grounded surface and maintain contact while handling the control).
• Avoid all plastic, vinyl, and Styrofoam (except antistatic versions) around printed circuit
boards.
• Do not touch the components or conductors on a printed circuit board with your hands
or with conductive devices.
IMPORTANT DEFINITIONS
• A WARNING indicates a potentially hazardous situation which, if not avoided, could result in
death or serious injury.
• A CAUTION indicates a potentially hazardous situation which, if not avoided, could result in
damage to equipment or property.
• A NOTE provides other helpful information that does not fall under the warning or caution
categories.
Woodward Governor Company reserves the right to update any portion of this publication at any time. Information
provided by Woodward Governor Company is believed to be correct and reliable. However, no responsibility is
assumed by Woodward Governor Company unless otherwise expressly undertaken.
© Woodward 1992
All Rights Reserved

Manual 02303 2301A Load Sharing & Speed Control
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Contents
ELECTROSTATIC DISCHARGE AWARENESS .................................................. II
CHAPTER 1. GENERAL INFORMATION...........................................................1
Description..............................................................................................................1
Applications ............................................................................................................2
CHAPTER 2. INSTALLATION..........................................................................8
Unpacking...............................................................................................................8
Power Requirements..............................................................................................8
Location Considerations.........................................................................................8
Electrical Connections............................................................................................8
Setting Speed Range .............................................................................................9
Potential Transformer Connections........................................................................9
Current Transformer Connections........................................................................10
Droop Contact (Isoch/Droop) and Load Sharing Lines ........................................10
Power Supply .......................................................................................................10
Minimum Fuel Contact..........................................................................................11
Failed Speed Signal Override ..............................................................................11
Idle/Rated Ramp Contact .....................................................................................11
Actuator Output ....................................................................................................11
External Speed Trim.............................................................................................12
Speed and Phase Matching (SPM) Synchronizer................................................12
Speed Sensor.......................................................................................................12
Installation Checkout Procedure ..........................................................................12
CHAPTER 3. OPERATION AND ADJUSTMENT...............................................14
Initial Pre-Start Settings........................................................................................14
Start-up Adjustments ............................................................................................14
Adjust for Stable Operation ..................................................................................15
Speed Sensor Check ...........................................................................................19
Current Transformer (CT) Phasing Check ...........................................................19
Load Gain Adjustment..........................................................................................23
Droop Adjustment.................................................................................................23
CHAPTER 4. DESCRIPTION OF OPERATION.................................................26
General.................................................................................................................26
Terminals for External Devices ............................................................................27
Paralleling.............................................................................................................28
CHAPTER 5. TROUBLESHOOTING...............................................................30
Troubleshooting Procedure ..................................................................................30
CHAPTER 6. SERVICE OPTIONS .................................................................36
Product Service Options.......................................................................................36
Returning Equipment for Repair...........................................................................37
Replacement Parts ...............................................................................................38
How to Contact Woodward...................................................................................38
Engineering Services ...........................................................................................39
Technical Assistance............................................................................................40
2301A CONTROL SPECIFICATIONS ............................................................43

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Illustrations and Tables
Figure 1-1. 2301A Load Sharing and Speed Control .............................................3
Figure 1-2. Plant Wiring Diagram (9900-430) ........................................................4
Figure 1-3. Plant Wiring Diagram (9900-431) ........................................................5
Figure 1-4. Plant Wiring Diagram (9900-432) ........................................................6
Figure 1-5. Plant Wiring Diagram (9900-433) ........................................................7
Figure 3-1. Diesel Engine Performance Curves...................................................17
Figure 3-2. Temporary Wiring for Transformer Phase Correction .......................21
Figure 3-3. Droop Adjustment ..............................................................................24
Figure 4-1. Speed Control System .......................................................................26
Figure 4-2. Terminal Connections ........................................................................28
Figure 4-3. Paralleling System .............................................................................29
Table 5-1. Troubleshooting ..................................................................................31
Electrostatic Discharge Awareness
All electronic equipment is static-sensitive, some components more than others.
To protect these components from static damage, you must take special
precautions to minimize or eliminate electrostatic discharges.
Follow these precautions when working with or near the control.
1. Before doing maintenance on the electronic control, discharge the static
electricity on your body to ground by touching and holding a grounded metal
object (pipes, cabinets, equipment, etc.).
2. Avoid the build-up of static electricity on your body by not wearing clothing
made of synthetic materials. Wear cotton or cotton-blend materials as much
as possible because these do not store static electric charges as much as
synthetics.
3. Keep plastic, vinyl, and Styrofoam materials (such as plastic or Styrofoam
cups, cup holders, cigarette packages, cellophane wrappers, vinyl books or
folders, plastic bottles, and plastic ash trays) away from the control, the
modules, and the work area as much as possible.
4. Do not remove the printed circuit board (PCB) from the control cabinet
unless absolutely necessary. If you must remove the PCB from the control
cabinet, follow these precautions:
•Do not touch any part of the PCB except the edges.
•Do not touch the electrical conductors, the connectors, or the
components with conductive devices or with your hands.
•When replacing a PCB, keep the new PCB in the plastic antistatic
protective bag it comes in until you are ready to install it. Immediately
after removing the old PCB from the control cabinet, place it in the
antistatic protective bag.
CAUTION—ELECTROSTATIC DISCHARGE
To prevent damage to electronic components caused by improper handling, read
and observe the precautions in Woodward manual 82715, Guide for Handling and
Protection of Electronic Controls, Printed Circuit Boards, and Modules.

Manual 02303 2301A Load Sharing & Speed Control
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Chapter 1.
General Information
Description
The Woodward 2301A load sharing and speed control operates the load sharing
and speed of generators driven by diesel or gasoline engines (it can also control
generators driven by steam or gas turbines).
This manual covers 2301A controls, part numbers:
• 9900-430 24 V power, forward-acting
• 9900-431 24 V power, reverse-acting
• 9900-432 110 V power, forward-acting
• 9900-433 110 V power, reverse-acting
The 2301A control is housed in a sheet-metal chassis and consists of a single
printed circuit board. All potentiometers are accessible from the front of the
chassis.
The 2301A provides control in either isochronous or droop mode.
The isochronous mode is used for constant engine speed with:
• Single-engine operation
• Two or more engines controlled by Woodward load sharing control systems
on an isolated bus
• Base loading against an infinite bus with the load controlled by an Automatic
Power Transfer and Load (APTL) Control, an Import/Export Control, a
Generator Loading Control, a Process Control, or another load-controlling
accessory
The droop mode is used for speed control as a function of load with:
• Single-engine operation on an infinite bus
• Parallel operation of two or more engines
The 2301A system for a single-engine generator includes:
• A 2301A electronic control
• An external 90 to 150 Vdc or 88 to 132 Vac 50/60 Hz high voltage power
source
• A speed-sensing device
• A proportional actuator to position the fuel- or steam-metering device
• Current and potential transformers for measuring the load carried by the
generator

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Applications
The 2301A electronic control has a switch-selectable speed range. The control
can be set to operate within one of the following rated speed ranges:
• 500 to 1 500 Hz
• 1000 to 3000 Hz
• 2000 to 6000 Hz
• 4000 to 12 000 Hz
WARNING—OVERSPEED
Speed range is factory set for 2000 Hz to 6000 Hz. Refer to inside cover to
change speed range and prevent possible overspeed. Using the wrong
speed range could cause an overspeed with resulting damage to equipment
and/or personal injury or death.
In forward-acting controls, the actuator calls for more fuel as the actuator voltage
increases. Loss of voltage to the actuator will drive the actuator to minimum fuel.
In reverse-acting controls, the actuator calls for more fuel as the actuator voltage
decreases. Loss of voltage to the actuator will drive the actuator to full fuel. This
allows a backup mechanical ballhead governor to take control rather than shut
down the engine as would a forward-acting system (reverse-acting controls with
mechanical ballhead backup governors are common on shipboard applications).
An optional deceleration ramp is also offered. When this option is present, the
time to ramp from rated speed to idle speed is approximately 20 seconds. If this
option is not present, this happens instantly.
NOTE
External wiring connections for reverse-acting controls are identical to
those for direct-acting controls.
The relationship between engine speed and sensor output frequency is
expressed in this formula: sensor frequency in Hz equals the number of teeth on
the speed sensing gear times the rated engine speed in revolutions per minute
divided by 60.
Frequency (Hz) = (No. of teeth) x (engine speed [rpm])
60

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Figure 1-1. 2301A Load Sharing and Speed Control

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Figure 1-2. Plant Wiring Diagram (9900-430)

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Figure 1-3. Plant Wiring Diagram (9900-431)

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Figure 1-4. Plant Wiring Diagram (9900-432)

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Figure 1-5. Plant Wiring Diagram (9900-433)

2301A Load Sharing & Speed Control Manual 02303
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Chapter 2.
Installation
Unpacking
Before handling the control, read the "Electrostatic Discharge Awareness"
section on page ii. Be careful when unpacking the electronic control. Check the
control for signs of damage such as bent or dented panels, scratches, and loose
or broken parts. If any damage is found, immediately notify the shipper.
Power Requirements
The high-voltage versions of the 2301A control requires a voltage source of 90 to
150 Vdc or 88 to 132 Vac 50/60 Hz for operating power. The low-voltage
versions require a voltage source of 20-40 Vdc. If a battery is used for operating
power, an alternator or other battery charging device is necessary to maintain a
stable supply voltage.
CAUTION—BATTERY
To prevent damage to the control, make sure that the alternator or other
battery-charging device is turned off or disconnected before disconnecting
the battery from the control.
Location Considerations
Consider these requirements when selecting the mounting location:
• Adequate ventilation for cooling
• Space for servicing and repair
• Protection from direct exposure to water or to a condensation-prone
environment
• Protection from high-voltage or high-current devices, or devices which
produce electromagnetic interference
• Avoidance of vibration
• Selection of a location that will provide an operating temperature range of -40
to +85 °C (–40 to +185 °F)
The control must NOT be mounted on the engine.
Electrical Connections
External wiring connections and shielding requirements for a typical control
installation are shown in the plant wiring diagram, Figure 1-2. These wiring
connections and shielding requirements are explained in the rest of this section.

Manual 02303 2301A Load Sharing & Speed Control
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Shielded Wiring
All shielded cable must be twisted conductor pairs. Do not attempt to tin the
braided shield. All signal lines should be shielded to prevent picking up stray
signals from adjacent equipment. Connect the shields to the control terminals as
shown in the plant wiring diagram, Figure 1-2. Wire exposed beyond the shield
should be as short as possible, not exceeding two inches. The other end of the
shields must be left open and insulated from any other conductor. Do not run
shielded signal wires with other wires carrying large currents. See Woodward
application note 50532, EMI Control for Electronic Governing Systems, for more
information.
Where shielded cable is required, cut the cable to the desired length and prepare
the cable as instructed below.
1. Strip outer insulation from BOTH ENDS exposing the braided or spiral
wrapped shield. DO NOT CUT THE SHIELD.
2. Using a sharp, pointed tool, carefully spread the strands of the shield.
3. Pull inner conductor(s) out of the shield. If shield is the braided type, twist to
prevent fraying.
4. Remove 6 mm (1/4 inch) of insulation from the inner conductor(s), and
connect the wiring and shield.
In installations with severe electromagnetic interference (EMI), shielded wire run
in conduit, double shielded wire, or other precautions may be required. Contact
Woodward for more information.
Setting Speed Range
The speed range to be selected is determined by the maximum desired engine
speed. Calculate the frequency of the speed sensor signal at the maximum
engine speed by multiplying the speed in revolutions per minute times the
number of teeth on the speed sensing gear and dividing by 60. Select the lowest
speed range which contains this maximum speed sensor frequency.
If the speed range must be changed, remove the cover. Carefully follow the
electrostatic procedures at the beginning of this chapter. Set the four rocker
switches on switch S1 (found on top of the printed circuit board on the far right
side near the top) as follows:
• 500–1500 Hz rocker switch 1 on, the other three switches off
• 1000–3000 Hz rocker switch 2 on, the other three switches off
• 2000–6000 Hz rocker switch 3 on, the other three switches off
• 4000–12 000 Hz rocker switch 4 on, the other three switches off
Potential Transformer Connections
Connect the potential transformer secondary leads to the following terminals:
• Phase A to terminal 1
• Phase B to terminal 2
• Phase C to terminal 3
The potential transformer secondary line-to-line voltage must be in the 90 to 240
Vrms range. Refer to the plant wiring diagram, Figure 1-2.

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Current Transformer Connections
The standard method of connecting the current transformers is shown in the
plant wiring diagram, Figure 1-2.
Droop Contact (Isoch/Droop) and Load Sharing Lines
Because the load-sharing-line relay is contained in the control, no relay is
required between the control and the load-sharing-line bus. Use shielded cable
and connect the load-sharing lines directly to terminals 10(+) and 11(–). Connect
the shield to terminal 12. When all controls in the system are of the 2301A type,
the shields may be connected continuously between controls. When load sharing
with different controls, do not connect the shields at the point where connections
are made to the load-sharing-line bus.
The droop contact for selecting droop or isochronous operation is wired in series
with the circuit-breaker auxiliary contact between terminals 14 and 16. When
both the droop contact and circuit-breaker auxiliary contact are closed, the
control is in the isochronous load-sharing mode. In this mode the internal load-
sharing-line relay is energized, the droop signal is disabled permitting
isochronous load sharing, and the load-matching circuit is connected to the load-
sharing lines.
The control is in the droop mode when EITHER the droop contact or the circuit-
breaker auxiliary contact is open. If the droop contact is open, the control
remains in the droop mode even when the circuit-breaker auxiliary contact is
closed.
NOTE
The control is in the droop mode whenever the circuit-breaker auxiliary
contact is open. If a single engine is required to run isochronously with an
isolated load, turn the DROOP potentiometer fully counterclockwise.
Droop operation is required when the generator is paralleled with an infinite bus
without a Generator Loading Control, Process Control, Automatic Power Transfer
and Load Control, Import/Export Control, or other load controlling accessory, or
when paralleled with incompatible governors. (All Woodward electric load-sharing
systems are compatible.) When running a single unit on an infinite bus with a
Generator Loading Control or Import/Export Control, terminal 14 must be
connected to terminal 16 to connect the Load Matching Circuit to the load-sharing
lines. The load-sharing lines must be wired to the Generator Loading Control or
Import/Export Control. The circuit-breaker auxiliary contact will then be connected
to the Generator Loading Control or Import/Export Control and not to the 2301A.
Power Supply
Run the power leads directly from the power source to the control, connecting
the negative lead to terminal 15, and the positive lead to terminal 16. If the power
source is a battery, be sure the system includes an alternator or other battery-
charging device.
CAUTION—DO NOT APPLY POWER
DO NOT apply power to the control at this time. Applying power before a
control is completely connected may damage the control.

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Minimum Fuel Contact
The minimum-fuel contact (terminal 17) is intended as an optional means for a
normal shutdown of the engine. It is connected in series with terminal 16 on low-
voltage models OR with terminal 0 on high-voltage models (see the plant wiring
diagram, Figure 1-2). If the minimum-fuel contact is not used, be sure there is a
jumper from terminal 17 to terminal 16 (low-voltage models) OR from terminal 17
to terminal 0 (high-voltage models). The control will not operate without 24 Vdc
applied to terminal 17.
When the contact is closed, the voltage applied to terminal 17 allows the control
to move the actuator to any position required for operating conditions.
WARNING—EMERGENCY STOP
To protect against possible serious injury or death resulting from engine
overspeed, DO NOT use the minimum-fuel contact as part of any emergency
stop sequence.
Failed Speed Signal Override
A contact to override the failed-speed-signal circuit can be installed in series with
terminal 18 and the dc power to the control (terminal 16 in low-voltage models
OR terminal 0 in high-voltage models). When the contact is open, the control
operates normally, turning the control output off in the event of a loss of speed
signal. Closing the contact overrides the failed-speed-signal circuit as may be
required for start-up.
Prior to start-up of the engine, the speed signal is non-existent. On engines with
cranking motors, the cranking speed is usually sufficient to provide a speed
signal, so an override contact on terminal 18 is not needed for starting. On some
steam turbine systems, the Close to Override Failed Speed Signal contact must
be closed in order to allow the actuator to open and provide steam for starting.
If a failed-speed-signal-override contact is used, it should be of the momentary
type to ensure that the failed-speed-sensor shutdown circuit is enabled after
start-up.
Idle/Rated Ramp Contact
The Close for Rated/Open for Idle terminal is terminal 19. Connect a single-pole,
single-throw contact from terminal 19 to terminal 16 in low-voltage models OR
from terminal 19 to terminal 0 in high-voltage models. Oil pressure is often used
to close this contact. When closed, 24 Vdc is applied to terminal 19, and the
engine can be operated at a speed higher than idle. When the contact is open,
the voltage is removed from terminal 19, and the engine's speed immediately
decelerates to idle.
Actuator Output
The actuator wires connect to terminals 20(+) and 21(–). Use shielded wires with
the shield connected to terminal 22. Do not connect the shield to the actuator or
any other point. The shield must have continuity the entire distance to the
actuator, and it must be insulated from all other conducting surfaces.

2301A Load Sharing & Speed Control Manual 02303
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External Speed Trim
A jumper must be connected to terminals 23 and 24 unless an optional remote
Speed Trim potentiometer is used. If a Speed Trim pot is used, connect it as
shown in the plant wiring diagram, Figure 1-2, using shielded wire. Connect the
shield to terminal 22. Make sure the shield has continuity the entire distance to
the pot, and that the shield is insulated from all other conducting surfaces. A 100
Ωpot will provide ±5% speed adjustment. If less adjustment is desired, pots of
smaller values may be used. Pots of the multiturn type are recommended.
Speed and Phase Matching (SPM) Synchronizer
Connect the SPM Synchronizer (optional equipment) wires to terminals 25(+)
and 26(–). Use shielded wire, and connect the shield to terminal 27. Make sure
the shield has continuity the entire distance to the SPM Synchronizer, but do not
connect the shield to the synchronizer. The shield must be insulated from all
other conducting surfaces.
Speed Sensor
Connect a speed-sensing device, such as a magnetic pickup, to terminals 28 and
29 using shielded wire. Connect the shield to terminal 27, making sure the shield
has continuity the entire distance to the speed sensor, and that the shield is
insulated from all other conducting surfaces.
Installation Checkout Procedure
With the installation completed as described in this chapter, perform the following
checkout procedures before beginning the start-up adjustments in Chapter 3.
1. Visual Inspection
A. Check the linkage between the actuator and the engine for looseness
or binding. Refer to the appropriate actuator manual and to manual
25070, Electronic Control Installation Guide, for additional information
on linkage.
WARNING—MINIMUM FUEL POSITION
To prevent possible serious injury or death, or damage to equipment, the
actuator lever must be near but not at its minimum position when the fuel or
steam rack is at its minimum position. If the actuator lever gets to its
minimum position before completely shutting off fuel or steam, the control
may not be able to shut down the turbine.
B. Check for correct wiring, using the plant wiring diagram, Figure 1-2.
C. Check for broken terminals and loose terminal screws.
D. Check the speed sensor for visible damage. If the sensor is a magnetic
pickup, check the clearance between the gear and the sensor, and
adjust if necessary. Clearance should be between 0.010 and 0.040
inch (0.25 and 1.0 millimeter) at the closest point. Make sure the gear
has less than 0.020 inch (0.5 mm) diametric runout. See manual
82510, Magnetic Pickups and Proximity Switches for Electronic
Controls.

Manual 02303 2301A Load Sharing & Speed Control
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2. Check for Grounds
Make sure power is off. Check for grounds by measuring the resistance
from terminal 11 to chassis, and from terminals 15 to 11. The resistance
should be infinite. If a resistance other than infinite is obtained, remove the
connections from each terminal one at a time until the resistance is infinite.
Check the line that was removed last to locate the fault.

2301A Load Sharing & Speed Control Manual 02303
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Chapter 3.
Operation and Adjustment
Initial Pre-Start Settings
WARNING—START-UP
To prevent possible serious injury or death from engine overspeed, or
damage to equipment from improper operation, carefully read and
understand this entire procedure before starting the engine.
1. RATED SPEED
A. Set the RATED SPEED potentiometer to minimum (fully
counterclockwise).
B. Set the external Speed Trim, if used, to mid-position.
2. RESET — Set at mid-position.
3. GAIN — Set at mid-position.
4. RAMP TIME — Set at maximum (fully clockwise).
5. LOW IDLE SPEED — Set at maximum (fully clockwise).
6. LOAD GAIN — Set at mid-position.
7. DROOP — Set at minimum (fully counterclockwise).
8. ACTUATOR COMPENSATION
A. Set the ACTUATOR COMPENSATION potentiometer at 2 on the 0 to
10 potentiometer scale for diesel, gas turbine, or fuel-injected gasoline
engines.
B. Set the ACTUATOR COMPENSATION potentiometer at 6 on the 0 to
10 potentiometer scale for carbureted-gas or gasoline engines, and
steam turbines.
9. START FUEL LIMIT — Set at maximum (fully clockwise).
10. Be sure the actuator is connected to terminals 20 and 21.
Start-up Adjustments
1. Complete the installation checkout procedure in Chapter 2, and the initial
pre-start settings above.
CAUTION—SPEED RANGE SWITCH
To prevent possible damage to the engine, be sure the speed range switch
is set on the right speed range for your application as described in Chapter
2.
2. Close the Close For Rated contact. Set the control for isochronous
operation by closing the droop contact.

Manual 02303 2301A Load Sharing & Speed Control
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NOTE
This is for initial engine start-up only. For normal start-up, the Close For
Rated contact should be open if the engine is to start at idle.
3. Apply input power to the control.
4. Preset rated speed.
If a signal generator is not used, set the RATED SPEED potentiometer at
minimum (fully counterclockwise).
When using a signal generator to set rated speed, set the signal generator
for the frequency of the speed sensor at rated speed, and connect it to
terminals 28 and 29. (The rated speed frequency in Hz equals the rated
engine speed in rpm times the number of teeth on the speed sensing gear
divided by 60.) Put the Close For Rated contact in the rated (closed)
position. Set the speed trim potentiometer, if used, to mid-position. Connect
a dc analog voltmeter to terminals 20(+) and 21(–) to read actuator voltage.
If the actuator voltage is at minimum (minimum will be approximately 0 V),
slowly turn the RATED SPEED potentiometer counterclockwise until the
voltage just begins to move to maximum.
If the actuator voltage is at maximum, slowly turn the RATED SPEED
potentiometer clockwise until the voltage just begins to move to minimum.
Continue to adjust the RATED SPEED potentiometer very slowly 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 slowly. The RATED
SPEED potentiometer is now set very close to desired speed. A slight
adjustment when the engine is running will achieve the exact speed.
5. Check the speed sensor.
Minimum voltage required from the speed sensor to operate the electronic
control is 1.0 Vrms, measured at cranking speed or the lowest controlling
speed. For this test, measure the voltage while cranking, with the speed
sensor connected to the control. Before cranking, be sure to prevent the
engine from starting. At 5% of the lower value of the control's speed range,
the failed speed sensing circuit is cleared. For example, 100 Hz is required
on the 2 000 to 6 000 Hz speed range (2 000 Hz x 0.05 = 100 Hz).
WARNING—START-UP
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.
6. Start the engine.
Adjust for Stable Operation
If engine operation is stable, go to the Speed Setting Adjustment procedure.

2301A Load Sharing & Speed Control Manual 02303
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If the engine is hunting at a rapid rate, slowly decrease the GAIN (turn the
potentiometer counterclockwise) until performance is stable. Adjusting the GAIN
may cause a momentary speed change which can be minimized by turning the
GAIN potentiometer slowly.
If the engine is hunting at a slow rate, increase the RESET (turn the
potentiometer clockwise) until the engine stabilizes. If increasing the RESET
potentiometer does not stabilize the engine, it also may be necessary to either:
• Slowly decrease the GAIN (turn the potentiometer counterclockwise) or
• Slowly decrease the GAIN and increase the ACTUATOR COMPENSATION.
Speed Setting Adjustment
With the engine operating stably, and the external speed trim potentiometer (if
used) set at mid-position, adjust the RATED SPEED potentiometer to bring the
engine to the desired operating speed.
Dynamic Adjustment
The object of the GAIN and RESET potentiometer adjustment is to obtain the
optimum stable engine-speed response.
Connect a dc analog voltmeter to terminals 20(+) and 21(–) to monitor the
actuator voltage.
NOTE
Adjusting the GAIN may cause momentary changes in speed which can be
minimized by turning the GAIN potentiometer slowly.
Increasing the setting of the GAIN potentiometer provides faster transient
response (decreases the magnitude of the speed change from a sudden change
in load). To achieve optimum response, slowly increase the GAIN (turn the
potentiometer clockwise) until the voltage on the voltmeter becomes slightly
unstable, then slowly turn the GAIN back counterclockwise as necessary to
stabilize the meter reading. Step load the generator, or bump the actuator
terminal shaft, to make sure that the engine returns to the proper speed with little
overshoot or undershoot of the speed setting. To reduce overshoot, increase the
RESET (turn the potentiometer clockwise).
When the RESET potentiometer is in the lower part of its adjustment (0 to 3 on
the potentiometer scale), increasing the RESET clockwise may require
decreasing the GAIN (turning the GAIN potentiometer counterclockwise) to
maintain stable operation.
If the engine is slow in returning to the proper speed, decrease the RESET by
turning the potentiometer counterclockwise.
Figure 3-1 illustrates engine starts with the RAMP TIME potentiometer fully
counterclockwise (no ramp), step loadings at four different RESET potentiometer
settings, and stable, steady-state running conditions. These are typical
performance curves on a naturally aspirated (non-turbocharged) diesel engine.
NOTE
Optimum performance is not necessarily obtained with the GAIN potentiometer
at the maximum stable clockwise position. In some cases, the gain must be
reduced slightly to ensure stability under widely varying conditions.