Woodward EPG 512 User manual

Product Manual 35162
(Revision -, 11/2019)
Original Instructions
EPG Electrically Powered Governors
with Single Phase Droop
RoHS Compliant
Models 512/524 and 1712/1724
UL Listed E97763
Installation and Operation Manual
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General
Precautions
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.
Revisions
This publication may have been revised or updated since this copy was produced.
To verify that you have the latest revision, check manual 26455, Customer
Publication Cross Reference and Revision Status & Distribution Restrictions, on
the publications page of the Woodward website:
www.woodward.com/publications
The latest version of most publications is available on the publications page. If
your publication is not there, please contact your customer service representative
to get the latest copy.
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.
Translated
Publications
If the cover of this publication states "Translation of the Original Instructions"
please note:
The original source of this publication may have been updated since this
translation was made. Be sure to check manual 26455, Customer Publication
Cross Reference and Revision Status & Distribution Restrictions, to verify whether
this translation is up to date. Out-of-date translations are marked with . Always
compare with the original for technical specifications and for proper and safe
installation and operation procedures.
Revisions—A bold, black line alongside the text identifies changes in this publication since the
last revision.
Woodward reserves the right to update any portion of this publication at any time. Information provided by Woodward is
believed to be correct and reliable. However, no responsibility is assumed by Woodward unless otherwise expressly
undertaken. Manual 35162
Copyright © Woodward, Inc. 2019
All Rights Reserved
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Contents
WARNINGS AND NOTICES............................................................................ 3
ELECTROSTATIC DISCHARGE AWARENESS.................................................. 4
CHAPTER 1. GENERAL INFORMATION .......................................................... 5
Application..............................................................................................................5
Part Number Selection ...........................................................................................5
Reference...............................................................................................................6
CHAPTER 2. INSTALLATION,CHECK,AND CALIBRATION............................... 7
General...................................................................................................................7
Speed Control Mounting.........................................................................................7
Actuator Mounting and Linkage..............................................................................7
Install Magnetic Pickup...........................................................................................8
CHAPTER 3. OPERATION........................................................................... 19
CHAPTER 4. DESCRIPTION ........................................................................ 20
Speed Control Applications..................................................................................20
Paralleled Generator Applications........................................................................23
CHAPTER 5. TROUBLESHOOTING............................................................... 24
CHAPTER 6PRODUCT SUPPORT AND SERVICE OPTIONS............................ 25
Product Support Options......................................................................................25
Product Service Options.......................................................................................25
Returning Equipment for Repair...........................................................................26
Replacement Parts...............................................................................................26
Engineering Services............................................................................................27
Contacting Woodward’s Support Organization ....................................................27
Technical Assistance............................................................................................28
REVISION HISTORY ................................................................................... 29
DECLARATIONS......................................................................................... 30
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Illustrations and Tables
Figure 1-1. Basic EPG System...............................................................................6
Figure 2-1. Typical Installation Kit..........................................................................8
Figure 2-2. Outline Drawing of EPG Speed Control...............................................9
Figure 2-3. Outline Drawing of EPG Actuators.......................................................9
Figure 2-4. Linear Linkage....................................................................................10
Figure 2-5. Carburetor Compensating Linkage at Minimum Fuel........................10
Figure 2-6. Carburetor Compensating Linkage at Maximum Fuel.......................10
Figure 2-7. Typical EPG (with droop) Wiring Diagram.........................................12
Figure 2-8. Droop Definition .................................................................................16
Figure 2-9. Correct and Incorrect Wiring to Battery..............................................17
Figure 2-10. Starting and Transient Response Curves........................................18
Figure 4-1a. EPG Block Schematic Diagram (standard)......................................21
Figure 4-1b. EPG Block Schematic Diagram.......................................................22
Figure 4-2. Actuator Schematic............................................................................23
Table 1-1. Part Number Selection Chart................................................................5
Table 2-1. Maximum Wiring Length Chart............................................................11
Table 2-2. Switch and Fuse Requirements Chart ................................................11
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Warnings and Notices
Important Definitions
This is the safety alert symbol used to alert you to potential personal injury hazards. Obey all
safety messages that follow this symbol to avoid possible injury or death.
DANGER - Indicates a hazardous situation, which if not avoided, will result in death or serious injury.
WARNING - Indicates a hazardous situation, which if not avoided, could result in death or serious
injury.
CAUTION - Indicates a hazardous situation, which if not avoided, could result in minor or moderate
injury.
NOTICE - Indicates a hazard that could result in property damage only (including damage to the
control).
IMPORTANT - Designates an operating tip or maintenance suggestion.
Lockout/Tagout
LOTO
Ensure that personnel are fully trained on LOTO procedures prior to
attempting to replace or service an EPG on a “live” running engine.
All safety protective systems (overspeed, over temperature,
overpressure, etc.) must be in proper operational condition prior to
the start or operation of a running engine. Personnel should be
equipped with appropriate personal protective equipment to
minimize the potential for injury due to release of hot hydraulic
fluids, exposure to hot surfaces and/or moving parts, or any moving
parts that may be activated and are located in the area of control of
the EPG.
Overspeed /
Overtemperature /
Overpressure
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.
Personal Protective
Equipment
The products described in this publication may present risks that
could lead to personal injury, loss of life, or property damage.
Always wear the appropriate personal protective equipment (PPE) for
the job at hand. Equipment that should be considered includes but is
not limited to:
Eye Protection
Hearing Protection
Hard Hat
Gloves
Safety Boots
Respirator
Always read the proper Material Safety Data Sheet (MSDS) for any
working fluid(s) and comply with recommended safety equipment.
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.
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On- and Off-Highway
Mobile Applications:
Unless Woodward's control functions as the supervisory control,
customer should install a system totally independent of the prime
mover control system that monitors for supervisory control of
engine (and takes appropriate action if supervisory control is lost) to
protect against loss of engine control with possible personal injury,
loss of life, or property damage.
Battery Charging
Device
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.
Electrostatic Discharge Awareness
Electrostatic
Precautions
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.
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.
Follow these precautions when working with or near the control.
1. 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.
2. 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.
External wiring connections for reverse-acting controls are identical
to those for direct-acting controls.
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Chapter 1.
General Information
Application
This manual covers only the part numbers of the system
components that are listed in the Part Number Selection Chart.
Contact Woodward or your authorized dealer or distributor for
information about other part numbers or applications.
The Model 1712/1724 and Model 512/524 Electrically Powered Governors (EPGs) are used to control the
speed of diesel, gas, and gasoline engines. They also can control the speed of gas turbines. Installation
of EPG actuators is simple because they require neither mechanical drive nor hydraulic supply.
These controls are intended for prime mover with generator loads. The advantage of these units is that
the DROOP circuitry is in the speed control.
An Electrically Powered Governor is a three-component system. A magnetic pickup, speed control, and
actuator are required.
A battery charger must be used to keep the battery charged. Maximum steady-state-current consumption
is 4 amps for the 12-volt model, and 3 amps for the 24-volt model.
Part Number Selection
Use EPG Model 1712/512 for operation in 12-volt systems. Use the Model 1724/524 for use in 24-volt
systems.
Additionally, speed controls are available for four ranges of magnetic pickup frequencies. These speed
controls are available for diesel engines and gas turbines or for gasoline and gas engines. Actuators have
a double ended output shaft for either clockwise (cw) or counterclockwise (ccw) rotation to increase fuel.
Speed controls and actuators must be compatible. Select compatible EPG controls and actuators from
Table 1-1.
Table 1-1. Part Number Selection Chart
For Use with
Prime Mover Type
System
Battery
Voltage
Single Phase Droop Control
Actuator
Part
Number
Speed Range (Hz) Required
750 to
1500
1500 to
3000
3000 to
6000
6000 to
12 000
Diesel and Gas
Turbine
24
8290-216*
8256-032
(*) These part numbers are EU directive compliant.
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Reference
These publications are available on the Woodward website (www.woodward.com).
Catalog 52122, Woodward Product Line Catalog
Product Specification 04106, EPG Electrically Powered Governors
Manual 25070, Electronic Control Installation Guide
Manual 82510, Magnetic Pickups and Proximity Switches for Electronic Controls
Figure 1-1. Basic EPG System
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Chapter 2.
Installation, Check, and Calibration
General
Custom installation kits, including actuator-mounting hardware, linkage, and actuator wiring harness are
available for some specific engines. Contact Woodward or your authorized dealer or distributor for more
information.
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.
Speed Control Mounting
The speed control is designed to operate within a temperature range of –40 to +75 °C (–40 to +167 °F).
Mount the control in a location with space for adjustment and wiring access. If mounted on the prime
mover, do not expose the speed control to sources of radiant heat, such as exhaust manifolds or
turbochargers. Also choose a protected location so the control won’t be damaged when moving the prime
mover or when equipment is moving nearby. Mount the control close to the actuator and battery to meet
the wire length requirements. Allow for adequate ventilation.
Actuator Mounting and Linkage
Actuator location must allow installation of a suitable linkage. The actuators are designed to operate
within a temperature range of –40 to +82 °C (–40 to +180 °F). Do not expose the actuator to sources of
excessive heat.
Match the actuator’s direction of rotation for increased fuel with the fuel control’s direction of rotation for
increased fuel by choosing a suitable linkage.
If you are using a Woodward-supplied installation kit, follow its instructions and skip over Linkage
Compatibility. Begin again with Installing the Magnetic Pickup.
Sealed bearings should not be pressure-washed. If the actuator is exposed to weather, mount it with the
clockwise end higher, if your installation allows it.
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Figure 2-1. Typical Installation Kit
Linkage Compatibility
Also match linkage to the fuel control. Use a linear linkage as shown in Figure
2-4 unless the prime mover has a carburetor or other nonlinear fuel control. See Figures 2-5 and 2-6 for a
carburetor compensating linkage. Contact Woodward if a linkage different from those shown is required.
Incorrect linearity matching can cause stable operation at some fuel settings but oscillation at other fuel
settings.
Manually stroke the fuel control linkage from stop to stop as if the actuator were moving it. The linkage
must move freely, without friction and without backlash. Lubricate or replace linkage or fuel control parts
as required.
Mount the actuator and install a suitable linkage.
A return spring is included in the actuator. Woodward recommends minimizing the external return force.
(Low-force return springs that may be located in an engine’s valve cover usually don’t affect EPG
performance.)
Make sure the actuator is capable of moving the fuel control to maximum and minimum limits. Let the fuel
control limit actuator travel. Set the linkage so the actuator is just above minimum when the fuel control is
at its minimum stop and, except for Detroit Diesel engines, just below maximum when the fuel control is at
its maximum stop. It is recommended that Woodward installation kits be used.
Use good rod-end connectors. The link connecting the actuator lever to the fuel-control lever must not be
so long that it flexes when the prime mover is running.
Install Magnetic Pickup
Mount the magnetic pickup (MPU) through a housing or rigid bracket. Make sure the sensed gear is
sensitive to magnetic fields The gap between the pickup and the outside diameter of the gear should be
set to approximately 1.02 mm (0.040 inch) at the closest point (radial runout). Using the pickup with small
gears may require spacing as close as 0.25 mm (0.010 inch).
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Figure 2-2. Outline Drawing of EPG Speed Control
(Do not use for construction.)
Figure 2-3. Outline Drawing of EPG Actuators
(EPG Models 1712/1724 left, Models 512/524 right)
(Do not use for construction.)
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Figure 2-4. Linear Linkage
Figure 2-5. Carburetor Compensating Linkage at Minimum Fuel
Figure 2-6. Carburetor Compensating Linkage at Maximum Fuel
If you cannot measure the gap directly, it can be set in this manner: With the prime mover shut down, turn
the pickup in until it touches the outside diameter of a tooth. Then back out the pickup ccw approximately
three-quarter turn. Run the gear slowly through 360 degrees of rotation to check clearance of pickup.
When the gap is set, tighten the jam nut securely against the housing or bracket.
The standard models of pickups require mating connectors, MS 3102R-18-3P. The connectors may be
ordered from Woodward or your authorized dealer or distributor if desired. More information is contained
in Woodward manual 82510, Magnetic Pickups and Proximity Switches for Electronic Controls.
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Wiring Instructions
Use a wiring diagram for the specific part number of your EPG system to make all wiring connections.
Typical wiring is shown in Figure 2-7.
Make all connections using insulated terminals. The wiring from the actuator to the speed control and
from the battery to the speed control must be as short as possible. Maximum wiring lengths are shown in
Table 2-1.:
Table 2-1. Maximum Wiring Length Chart
EPG Model
Maximum Wire Length
14 AWG
(2 mm²)
12 AWG
(4 mm²)
1712/512
10 ft (3 m)
20 ft (6 m)
1724/524
35 ft (11 m)
75 ft (23 m)
The fuse and switch or circuit breaker must be in the non-grounded battery lead. Use a fuse or circuit
breaker as specified in Table 2-2. Do not use a fuse of higher current rating. Starter relays make good
EPG power switches.
Table 2-2. Switch and Fuse Requirements Chart
Model
Voltage
Switch
Rating
Fuse
1712/512
12
10 A
10 A
1724/524
24
10 A
10 A
The battery connection to speed control terminals 1 and 2 must be directly from the terminals, not through
distribution points. See Figure 2-9.
Do not connect any other wire to terminals 1 and 2 except the power for the 2500 ramp generator, if used.
To prevent damage to the control, disconnect the battery charger
from the battery before disconnecting the leads from the control to
the battery.
Connect power wires directly to the battery terminals. The speed
control can be damaged If those wires are connected to distribution
points. See Figure 2-9.
Shields
Connect shields as shown in your wiring diagram. Terminate shields at a chassis mounting screw. Only
one end of each shield, the end nearest the speed control, should be tied to ground. All shields must be
tied to the same point.
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Figure 2-7. Typical EPG (with droop) Wiring Diagram
When passing shields through connectors to terminal blocks, treat each shield as if it were a signal wire.
Each shield must be given its own pin or terminal and be kept insulated from nearby wires and metal
conductors. Do not tin (solder) braided shields.
Connect the speed control chassis to system ground (connect to earth ground).
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Installation Checks
Checks for All Applications
The following steps check only the speed control and actuator. They must work correctly before
paralleling the generator. Since most faults appear when the prime mover is first run, this step by step
approach eliminates most problems before they occur. Also, the main part of Chapter 5, Troubleshooting,
covers these checks.
The generator must not be paralleled during these tests. If a Ramp Generator is used, then temporarily
remove the wire at speed control terminal 8, which goes to the ramp generator. Leave the idle-rated
switch wiring connected. Perform the checks in the order indicated. Terminal numbers in this chapter refer
to the speed control.
1. Make sure all electrical connections are correctly made and terminal screws tightened; the magnetic
pickup is properly installed and jam nut tightened; the actuator and linkage are securely fastened.
2. Do not start the prime mover now. Turn on governor power. If the fuse or breaker opens as soon as
power is applied, the battery polarity (terminals 1 and 2) is probably reversed. The actuator shaft can
jump when power is turned on, but must quickly come back to the minimum-fuel position. Check the
battery voltage at terminal 1 (+) and 2 (–). It must be from 10 to 16 Vdc for EPG Model 1712 control
and from 20 to 32 Vdc for Model 1724.
3. Disconnect any wiring or jumper on terminal 7. Measure voltage from 2 (–) to 7 (+). The voltage must
be 7.2 ±1 volt. If voltage is correct, then re-install the wiring to terminal 7.
4. If idle speed is desired, connect a 50 kpotentiometer or fixed resistor to terminals 7 and 8 as
shown in the typical wiring diagram. To calculate the value of a fixed resistor:
R = 17 k(
Rated Speed
Idle Speed
–1)
5. Put the idle-rated switch in the rated position. Measure the voltage from terminal 7 (+) to 2 (–). Put
the idle-rated switch in the idle position. The voltage must increase. If it does not increase, check the
speed trim pot, if used, and idle-rated switch wiring.
6. If a signal generator with an isolated output is available, the failsafe and actuator travel can be
checked. Rated and idle speeds can be preset. If a signal generator is not available, skip to Step 7.
Turn governor power off. Remove the magnetic pickup wires from terminals 5 and 6. Connect the
signal generator to terminals 5 and 6. Set the output between 2 and 10 Vrms. The waveform can be
sine, square, or triangular. Calculate the MPU frequency for idle and rated speeds. See part number
selection in Chapter 1.
6.1 Check Failsafe and Actuator Travel
Set the signal generator frequency to about half idle speed. Set the idle-rated 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 make sure 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. Make
sure linkage travel is limited by the prime mover’s fuel control, not by the actuator stop.
6.2 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 ccw until the linkage just begins to move to the minimum-fuel
position.
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If the linkage is at the minimum-fuel position:
Slowly turn the rated-speed pot (cw) clockwise until the linkage just begins to move to the
maximum-fuel position.
Continue to very slowly adjust the rated speed pot 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.
6.3 Preset Idle Speed.
Preset idle speed only after presetting rated speed. Set the signal generator for 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 ccw until the linkage just begins to move to the minimum-fuel
position.
If the linkage is at the minimum-fuel position:
Slowly turn the idle speed pot cw until the linkage just begins to move to the maximum-fuel
position.
Continue to very slowly adjust the idle-speed pot 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.
7. If the idle and rated speed pots were not preset with a signal generator, set the rated-speed pot fully
ccw.
8. Remove the MPU wires from speed-control terminals S and 6. Measure the resistance of the MPU at
the wire ends. It should be between 100 and 300 ohms. Reconnect the MPU wires.
9. Set the idle-rated switch for rated speed. Turn governor power on.
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.
10. Gain And Stability
Set the gain and stability pots to mid position. Connect an ac voltmeter to speed-control terminals 5
and 6 to measure the MPU voltage. Start the prime mover following manufacturer’s instructions, and
check the MPU voltage. It must be at least 1.5 Vrms while cranking.
If the prime mover does not start, check the linkage while cranking. If it is at the maximum-fuel
position the EPG is operating correctly. Check the fuel supply, ignition, etc.
If the linkage is not at the maximum-fuel position, cranking speed can be greater than the speed
reference. Measure the resistance from speed control terminal 7 to 8. It must be a short circuit
(0 ohms). If not, the idle-rated switch is in the idle position or the switch or wiring is defective.
Place in rated position or repair. If the resistance is 0 ohms the rated-speed reference can be
lower than cranking speed. Turn the rated-speed pot cw four turns and try to restart. Be
prepared to quickly adjust rated speed ccw to minimize overspeed if the prime mover starts. If it
still doesn’t start, turn the rated speed pot fully ccw to minimize overspeed when it does start.
Refer to Chapter 5, Troubleshooting.
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When the prime mover starts, slowly turn the gain pot back and forth to observe high- and low-
frequency oscillation. Eliminate oscillation by slowly turning the gain pot for the stable region
between high- and low-frequency oscillation. If the oscillation does not stop at the high-low
crossover, turn the stability pot slightly ccw and slowly readjust the gain pot. Continue adjusting
the stability pot slightly ccw followed by readjusting gain until the prime mover runs at a steady
speed.
10.1Set Transient Response
By turning gain slightly cw and stability slightly ccw, or vice versa, it is possible to maintain
stable speed and vary transient response. See response-curve diagram. Its four curves are
examples of a naturally aspirated (not turbocharged) diesel engine. Note that increasing the
gain and decreasing the stability causes shorter settling times at the expense of ringing. The
use of chart recorder makes it easier to observe transient response.
Check response after each adjustment by disturbing the engine off and on, step loading the
engine, manually bumping the linkage, or quickly switching to idle speed and then back to rated.
Repeat the following tuning procedure until the prime mover responds as desired. Note that
“tight settings” gain high as possible with given stability setting, can result in stable operation at
normal temperatures and oscillation when the prime mover is cold.
To decrease settling time, turn the gain pot cw. Turn the stability pot ccw as required to
eliminate oscillation and obtain desired response.
To decrease ringing, turn the stability gain pot cw. Turn the gain pot ccw as required to
eliminate oscillation and obtain desired response.
Check response by step loading the engine, disturbing the engine off and on, manually bumping
the linkage, or quickly switching to idle speed and back to rated.
11. Setting Speed References
The prime mover should not be oscillating. Make sure the idle-rated switch is in the rated-speed
position. Adjust the rated-speed pot for exact rated speed. Set the idle-rated switch for idle speed.
Adjust the idle speed pot for desired idle speed. Set the idle-rated switch back to rated.
Droop Adjustment
Adjustment of the droop potentiometer is necessary when droop mode operation of the control is
required. Droop can be set with either of the following methods.
Droop is usually expressed as a percentage and calculated by:
% Droop =
No Load Speed –Full Load Speed
No Load Speed
X 100
For setting DROOP on an isolated load:
1. Adjust the control for rated speed with no load.
2. Apply load, 100% load if possible.
3. Adjust DROOP potentiometer to give the desired speed. Operating at 60 Hz, 57 Hz at full load
indicates 50/0 droop. If only 500/0 loading is possible, 58.5 Hz would indicate 5% droop. See Figure
2-8, Droop Definition.
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Figure 2-8. Droop Definition
For setting DROOP with a system operating into an infinite bus:
1. With the generator not paralleled, adjust the RATED SPEED POTENTIOMETER to give a speed
setting above 60 Hz by the percent droop required. (For example, 5% droop would require raising
the speed to 63 Hz.) Mark the potentiometer position and return to 60 Hz.
2. Turn the DROOP potentiometer fully cw (for maximum droop).
3. Synchronize the generator to the bus and parallel it to the line.
4. Return RATED SPEED potentiometer to the mark made in Step 1.
5. Adjust the DROOP potentiometer ccw, decreasing droop, until 1000/0 load is achieved.
If load other than 100% is desired, the speed pot will have to be set
accordingly for desired percent droop. For example, at 5% droop, a
50% load-speed setting would be for 61.5 Hz.
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Figure 2-9. Correct and Incorrect Wiring to Battery
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Figure 2-10. Starting and Transient Response Curves
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