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