8290-189-EPG-installation-manual 8290-044
Installation and Operation Manual
This manual covers Electrically Power Governor (EPG) models 512/524 and
1712/1724. Refer to the appropriate manual or contact Woodward for information
about other versions of the EPG.

Application
The EPG is used to control the speed of diesel, gas, and gasoline engines. It can
also control the speed of gas turbines. Installation of EPG actuators is simple
because they require neither mechanical drive nor hydraulic supply.
The EPG handles prime movers with mechanical loads and generator loads
equally well. Generator sets which will be paralleled, however, require additional
appropriate switch gear, current and potential transformers, and the Woodward
Generator Load Sensor.
An EPG is a three-component system, requiring a magnetic pickup, speed
control, and actuator.
A battery charger must be used to keep the battery charged. Maximum steady
state current consumption is 4 A for the 12-volt models (512/1712), and 3 A for
the 24-volt models (524/1724).
Part Number Selection
Use EPG Model 512/1712 for operation in 12-volt systems. Use Model 524/1724
for operation in 24-volt systems.
Additionally, speed controls are available for four ranges of magnetic pickup
frequencies, for diesel engines and gas turbines, or for gasoline and gas
engines. Actuators have a double-ended output shaft for either clockwise or
counterclockwise rotation to increase fuel.
Speed controls and actuators must be compatible. Use the Part Number
Selection Table below (Table 1-1) to choose compatible EPG speed controls and
actuators.
The optional Start Fuel Limit feature allows setting a maximum actuator position
during start-up. The maximum position remains in effect until the engine reaches
the selected idle or rated speed. The limit may be adjusted out of the way by
turning the adjustment potentiometer fully clockwise.
The Dual Dynamics feature allows tailoring a special set of responses for
unloaded and loaded operating conditions. This type of control is often needed
for gas engines and other systems with non-linear fuel systems. A switch is used
to change between slow and fast dynamics.
Accessories
This manual includes some information about accessories frequently used with
EPGs.
To Parallel Generators
Add the Generator Load Sensor to the EPG in paralleled generator applications.
Woodward makes many accessories for paralleled generator applications.
To Decrease Acceleration and Deceleration
The Ramp Generator or an optional, external capacitor can be used to increase
the time to go from idle to rated speeds and vice versa. The Ramp Generator
provides a linear ramp with times adjustable to 25 seconds in a typical case. It is
useful in smoke-limiting applications. Use the 8271-909 with 24 V batteries and
the 8271-910 for 12 V batteries. The capacitor provides an exponential ramp with
times up to four seconds. Exponential means it changes (speed in this case)
rapidly at first but slows as it approaches its final value. See the typical wiring
diagram for capacitor requirements.
References
These publications can be obtained from your Woodward authorized Distributor
or AISF (Authorized Independent Service Facility). All are also available on the
Woodward website (www.woodward.com).
Catalog
52122
Product
Specification
04106
Manual
25070
82510
Title
Woodward Industrial Control Product Line Catalog
Title
Model 512/1712 & 524/1724 Electrically Powered Governors
Title
Electric Governor Installation Guide
Magnetic Pickups for Electric Governors
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.
Linkage Compatibility
Also match linkage linearity to the fuel control. Use a linear linkage as shown in
Figure 2-2 unless the prime mover has a carburetor or other non-linear fuel
control. See Figures 2-3 and 2-4 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.
A return spring is included in the actuator. Do not use an additional return spring.
(Low force return springs that may be located in an engine’s valve cover usually
don’t affect EPG performance.)
Make sure that the actuator is capable of moving the fuel control to the maximum
and minimum limits. Let the fuel control limit actuator travel. Set the linkage so
that the actuator is just above minimum when the fuel control is at its minimum
stop and (except for Detroit Diesel engines) so that the actuator is just below
maximum when the fuel control is at its maximum stop. We recommend that
Woodward installation kits be used for Detroit Diesel engines.
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.
Installing the Magnetic Pickup
Mount the magnetic pickup through a housing or rigid bracket. Make sure that
the sensed gear is of magnetic material. The gap between the pickup and the