engine will shut off.
Release the TEST button. After the engine stops, press the
RESET button or remove battery power. Restart the engine
and it will return to the original speed setting. The overspeed
function is now set to approximately 10% above the request-
ed speed.
If a different value of overspeed setting is required, raise the
engine speed to the desired overspeed value, i.e. 115%. Ro-
tate the OVERSPEED adjustment CCW until the red OVER-
SPEED LED lights and the relay energizes
.
⚠
WARNING
Always use the relay contacts provided to shut down the
system by a means other than the governor or actuator. It
is recom-mended that an overspeed protection sys-tem be
routinely tested and verified during the scheduled service
of equipment.
Governor Speed Setting
The governed speed set point is increased by a CW rotation
of the SPEED adjustment control. Remote speed adjust-
ment can be obtained with an optional 5K Speed Trim Con-
trol. (See Diagram 1.)
Governor Performance
Once the engine is at operating speed and at no load, the
following governor performance adjustment can be made.
A.
Rotate the GAIN adjustment CW until instability devel-
ops. Gradually move the adjustment CCW until stability
returns. Move the adjustment one division further CCW
to insure stable performance.
B.
Rotate the STABILITY adjustment clockwise until insta-
bility develops. Gradually move the adjustment coun-
terclockwise until stability returns. Move the adjustment
one division further to insure stable performance (270°
pot).
C.
GAIN and STABILITY adjustments may require minor
changes after engine load is applied. Normally, ad-
justments made at no load achieve satisfactory perfor-
mance. A strip chart recorder can be used to further
optimize the adjustments.
If instability cannot be corrected or further performance
improvements are required, refer below to the SYSTEM
TROUBLESHOOTING section.
Starting Fuel Adjustment
The engine’s exhaust smoke at start-up can be minimized
by completing the following adjustments:
A.
Place the engine in idle by connecting Terminals M & G.
B.
Adjust the IDLE speed for as low a speed setting as the
application allows.
C.
Adjust the STARTING FUEL CCW until the engine speed
begins to fall. Increase the STARTING FUEL slightly so
that the idle speed is returned to the desired level.
D. Stop the engine.
One of two methods of operation for the ESD5550/5570
may now selected. (See Table 2.)
Table 2 Starting Method
Method 1
Method 2
Start the engine and accelerate
Start the engine and control
directly to the operating speed
at an idle speed for a period of
(Gen Sets, etc.).
time prior to accelerating to the
operating speed. This method
separates the starting process
so that each may be optimized
for the lowest smoke emissions.
Remove the connection between
Replace the connection be-
Terminals M & G. Start the en-
OR
tween Terminals M & G with a
gine and adjust the SPEED
switch, usually an oil pressure
RAMPING for the least smoke
switch. Start the engine. If the
on acceleration from idle to rated
starting smoke is excessive,
speed. If the starting smoke is
the STARTING FUEL may need
excessive, the STARTING FUEL
to be adjusted slightly CCW. If
may need to be adjusted slightly
the starting time is too long, the
CCW. If the starting time is too
STARTING FUEL may need to
long, the STARTING FUEL may
be adjusted slightly CW.
need to be adjusted slightly CW.
When the switch opens, adjust
the SPEED RAMPING for the
least amount of smoke when
accelerating from idle speed to
rated speed.
Idle Speed Setting
If the IDLE speed setting was not adjusted as detailed in
‘Starting Fuel Adjustment’ section, then place the optional
external selector switch in the IDLE position. A CW adjust-
ment to the IDLE adjustment control will increase the idle
speed set point. When the engine is at idle speed, the speed
control unit applies droop to the governor system to insure
stable operation.
Speed Droop Operation
Droop is typically used for the paralleling of engine driven
generators.
Place the optional external selector switch in the DROOP po-
sition. DROOP is increased by CW rotation of the DROOP
adjustment control. When in droop operation, the engine
speed will decrease as engine load increases. The percent-
age of droop is based on the actuator current change from
engine no load to full load. A wide range droop is available
with the internal control. Droop level requirements above
10% are unusual.
If droop levels experienced are higher or lower then these
required, contact GAC for assistance.
After the droop level has been adjusted, the rated engine
speed setting may need to be reset. Check the engines
speed and adjust that speed setting accordingly.
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