8290-189-EPG-installation-manual 8290-044

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

outside diameter of the gear should be set to approximately 1.0 mm (0.04”) at the

closest point (radial runout). Using the pickup with small gears may require

spacing as close as 0.25 mm (0.010”).

If you cannot measure the gap directly, it can be set in this manner: with the

prime mover shut down, turn the pickup in (clockwise) until it touches the outside

diameter of a tooth. Then back out the pickup (counterclockwise) approximately

three-quarters of a turn. Run the gear slowly through 360 degree rotation to

check the clearance of the pickup. When the gap is set, tighten the jam nut

securely against the housing or bracket.

The standard pickup models require mating connectors, MS 3102R-18-3P. The

connectors are not furnished with the pickup, but may be ordered from

Woodward if desired. See manual 82510. Magnetic Pickups and Proximity

Switches for Electronic Controls, for more information

Wiring Instructions

Use a wiring diagram for the specific part number of your EPG system to make

all wiring connections. The wiring diagram is available from Woodward. Typical

wiring is shown in Figure 2-5.

Make all connections using insulated terminals. The wiring from actuator to

speed control and from the battery to the speed control must be as short as

possible. Maximum wiring lengths are:

Maximum Wiring Length Chart

EPG Model

14 AWG

(2 mm²)

Maximum Wire Length

12 AWG

(3 mm²)

512/1712

10 ft (3 m)

524/1724

20 ft (6 m)

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 the Switch and Fuse Requirements

Chart. Do not use a fuse of higher current rating. Starter relays make good EPG

power switches.

Installation Checks

Checks for all Applications

The following steps check only the speed control and actuator, which 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. The main part of Chapter 5 (Troubleshooting) is doing these

checks.

If a Load Sensor is used, temporarily remove the wires at speed control terminals

11 and 12 and temporarily jumper terminals 11 to 12. The generator must not be

paralleled during these tests. If a Ramp Generator is used, temporarily remove

the wire at speed control terminal 10. If a capacitor is connected to terminal 10 to

provide a ramp between unloaded and loaded, it must be removed during this

test or calibration. Leave the idle-rated switch wiring connected. Do the checks in

the order indicated. Terminal numbers in this section refer to the speed control.

Check that all electrical connections are correctly made and terminal screws

are tight; the magnetic pickup is properly installed and the jam nut is tight;

the actuator and linkage are securely fastened. If start-fuel limit is present,

turn the adjustment fully clockwise during these tests. If dual dynamics are

present, set the switch closed for slow dynamics.

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

14 and 15) 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 512/1712 controls, and from 20 to 32 Vdc for 524/1724 controls.

Disconnect any wiring or jumper on terminal 7. Measure 7.2 ±1.0 V from

terminal 2 (–) to 7 (+) [terminals 2 (–) to 9 (+) for dual-dynamics control].

Reinstall the wiring to terminal 7 if voltage is correct. Do not use the control

if voltage is incorrect.

If idle speed is desired, connect a 50 kΩ potentiometer or fixed resistor to

terminals 9 and 10 as shown in the typical wiring diagram. To calculate the

value of a fixed resistor:

R = 17 kΩ

( Rated Speed

Idle Speed – 1 )

Put the idle-rated switch in the rated position or jumper terminals 9 and 10.

Measure the voltage from terminal 7 (+) to 2 (–). Put the idle-rated switch in

the idle position or remove the jumper. The voltage must increase. If it does

not increase, check the speed trim pot, if used, and the idle-rated switch

wiring.

If a signal generator with an isolated output is available, the failsafe and

actuator travel can be checked, Rated and idle speed can be preset. If a

signal generator is not available, skip to step 7.

Turn off governor power. 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 wave form can be sine, square, or triangular.

Calculate the MPU frequency for idle and rated speeds (see part number

selection in Chapter 1).

Check Failsafe and Actuator Travel:

Set the signal-generator frequency to about half of 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, verify that 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. Verify that linkage travel is limited by the prime mover’s fuel

control, not by the actuator stop.

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 counterclockwise until the linkage just

begins to move to the minimum fuel position. Start Fuel (if present) must be

adjusted to the maximum clockwise position or the actuator will not move to

maximum.

If the linkage Is at the minimum fuel position:

Slowly turn the rated speed pot clockwise until the linkage just begins to

move to the maximum fuel position.

Continue to adjust the rated speed pot very slowly 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.

Preset Idle Speed:

Preset idle speed only after presetting rated speed. Set the signal generator

for the MPU frequency at idle speed. Put the idle-rated switch in the idle

pos