WOODWARD PSG GOVERNOR
TESTING AND ADJUSTING
1. Synchronizing motor. 2. Knurled knob. 3.
Locknut 4. Stop screw.
CHECK SPEED DROOP
The speed droop can be adjusted between zero and
seven percent. The desired speed droop will be different
for different applications. Percent of speed droop is the
percent difference between the engine speed at no load
and full load. To calculate speed droop use the formula:
No load speed-Full load speed X 100 =speed
Full load speed
Get the desired speed droop for the application.
Multiply the full load speed by the desired speed
droop. Add the number from this multiplication
to the full load speed to get the no load speed.
Start the engine and let it run until the
temperature of the coolant is normal.
Adjust the engine speed to get the no load speed
from Step 2.
Connect a known load to the engine. The load
must be less than the full capacity of the engine.
Make a record of the decrease in engine speed.
Make a ratio between the load on the engine and
the full load capacity of the engine. This ratio
must be the same as the ratio between the
decrease in engine speed from Step 5 and the
number from the multiplication in Step 2, For
50 HP (known load)
100 HP (full load capacity)
45 rpm (decrease in engine speed from step 5)
90 rpm (number from multiplication in step 2)
If the ratios are not the same, an adjustment of the
speed droop is necessary. Remove the load and
stop the engine. If the engine speed decreased too
much according to the ratio decrease, the amount
of speed droop. If the decrease in engine speed is
not enough, increase the amount of speed droop.
See SPEED DROOP ADJUSTMENT.
SPEED DROOP ADJUSTMENT
Make a mark on cover (1) to show the original
position of bracket (3). This will show how much a
change in bracket position changes the speed
Loosen knob (2) that holds bracket (3) and speed
droop lever (4) in position.
1. Cover. 2. Knob. 3. Bracket 4. Speed droop
lever. 5. Stop screw.
To increase the speed droop turn lever (4)
counterclockwise. To decrease the speed droop
turn lever (4) clockwise.
NOTE: If the lever is turned clockwise beyond the point
where the speed droop is zero the engine will hunt a
large amount and will not get stability.