Westerbeke 8.0 KW-60Hz SBEG Operator's Manual page 23

ELECTRONIC FUEL INJECTION
FUEL "«'UL'''U''\.
STEPPER MOTOR AND
THROTTLE SHAft
ASSEMBLY
THRonLE BODY
UPPER THROTTLE
LOWER THROTTLE
AIR TEMPERATURE BODY
SENSOR
The above illustration shows tl,e throttle body assembly that
attaches to the intake manifold.
An electronic control unit (ECU) controls the fuel injector
and the stepper motor.
The ECV is supplied with engine operating conditions from
sensors that monitor intake air temperature, engine coolant
temperature, map sensor (intake manifold absolute pressure),
engine rpm and battery voltage.
The ECV interprets this information to determine the
appropriate injector pulse rate and throttle opening position.
A high pressure fuel pump supplies fuel to the area around
the injector and the regulator maintains the fuel pressure in
that area at 35 - 40 PSI maximum.
The injector is a solenoid operated pintle valve that meters
fuel into the intake manifold depending on engine operating
conditions and generator amperage load determined by the
ECV.
Air flow into the intake manifold is controlled by the ECV
operation of the throttle plate via the stepper motor. Throttle
plate positioning for proper air flow mto the engme is
accomplished through the ECV interpretation of engine
operating conditions. The Schrader valve is used to
monitor/check fuel pressure around the fuel injector.
ELECTRONIC CONTROL UNIT (ECU)
The ECV (Electronic Control Vnit) is factory programmed
NOTE:
When changing the generator frequency. turn OFF
the DC 20 amp breaker before moving the dipswich.
The vacant program connector is used by the factory to input
the operating program into the ECV. This connector can be
used with purchased software to monitor the operation of the
Safe CO systems.
The electrical connections from the engine electrical harness
are made to the ECV through two plug connections, one 23
pin and one 35 pin and may therefore vary in number
according to the generator model. For further details. consult
the engine circuit wiring diagram in this manual.
The ECV is normally set for operation at 60Hz unless
specified otherwise, and is internally configured for a 4 pole
generator. If it is necessary to replace the ECV, make sure it
is configured by label for the generator in use.
ECU ADJUSTMENTS
Stability Trim (Gain)
When changing engine speed. or if no engine hunting
condition should occur, the gain pot may require adjustment.
There is no specific set point for this adjustment and it is
normally set to the middle of its range or to a point in its
range which obtains optimal engine speed response without
any tendency of hunting.
Setting Engine Speed
The engine speed can be set for operation at either 50 or 60
Hz. Corresponding engine speeds for a 4 pole generator are
1500 rpm or 1800 rpm.
1. Set up whatever equipment is to be used to measure
engine speed or generator output frequency.
2. Start up and run the generator at the current operating
speed and frequency. .
3. Adjust the GAIN setting between 40 - 60 for best system
reaction to AC amperage load changes.
NOTE: A
higher GAIN adjustment can induce unstable engine
operation. In such cases, lessen the GAIN adjustment.
Replacing the ECU
Remove the control box cover. Before attempting to remove
the ECU, turn OFF the 20 amp DC control panel breaker.
Unplug the two engine harness connections. Then unscrew
the four side screws securing the ECU and remove it from
it's holder. To install a new ECU, reverse the procedure.
ECU
and requires no adjustments by the generator operator. It
PROGRAM
controls all starting, operating and safety shutdown features
on the engine. The Gain Pot is set at #50 midpoint for
optimum system response.
Dipswitch #1 is used to charge the generators frequency.
ON is for 50 hertz and OFF is for 60 hertz operation. The
remaining switches #2, 3#. and #4 service no functions.
-..v-
WESTERBEKE
Engines & Generators
128
ADJUSTMENT POT