Westerbeke SBEG Series Operator's Manual page 19

SAFETY SHUTDOWN SENSORS AND SWITCHES
SAFETY SHUTDDWN SWITCH/SENSDRS
The engine is protected by four automatic shutdown circuits.
Should a shutdown occur, do not attempt to restart without
finding and correcting the cause. Refer to the heading
Engine stans, runs and then shuts down in the ENGINE
TROUBLESHOOTING section of this manual.
The following is a description of these automatic shutdown
circuits:
High Exhaust Temperature Switch
An exhaust temperature switch is located on the water
injected exhaust elbow. Nonnally closed, this switch will
open and the ECU will interpret this as a high exhaust
temperature and open the K2 run relay, stopping the
generator. The exhaust temperature LED on the panel will
illuminate. The switch opens at 260-270F (127-132C). This
switch resets (contacts close) at approximately 225F (I07C).
• HIGH EXHAUST
. TEMPERATURE SWITCH
Water Temperature Sensor
II
!I
MOUNTED ATTHE
EXHAUST ELBOW
A water temperature sensor is located at the thermostat
housing. This sensor sends a DC voltage to the ECU that it
interprets as engine antifreeze coolant temperature. Should
this voltage reach a set value, the ECU will interpret this as
high antifreeze coolant temperature and open the K2 run
relay, stopping the generator. The overheat LED on the panel
will then illuminate.
WATER TEMPERATURE SENSOR
Oil Pressure Sensor
An oil pressure sensor is located off the engines oil gallery.
Oil pressure on the sensor affects the DC voltage through the
sensor to the ECU. Should the voltage reach a preset value,
the ECU will interpret this as a low oil pressure issue and
open the K2 run relay, stopping the generator. The oil
pressure LED on the panel will illuminate.
Engine DC Circuit Breaker
OIL PRESSURE
SENSOR
The generator's engine DC circuit is protected by a rocker
type DC 20 amp breaker mounted on the control box. This
also serves as an Emergency Stop Switch. Excessive DC
current draw or DC electrical overload anywhere in the
instrument panel wiring or engine wiring will cause the
breaker to trip to the OFF position. In this event, the DC
power to the ECU will be interrupted, stopping the generator.
No panel LED will illuminate. Check and repair the source
of the problem. After repairing the fault, reset the breaker and
restart the generator.
High/low RPM Shutdown
Should the generator's RPM go above 20% of the specified
1800 rpm
@
60 Hzl1500 rpm
@
50
Hz,
the ECU will shut
the engine down on an over speed fault and illuminate the
over speed LED on the control panel and remote starUstop
panel when installed
Should the generator's RPM fall below 20% of the specified
1800 rpm
@
60 Hzl1500 rpm
@
50 Hz, the ECU will shut
the
enJllil~dQwn
on
JIll
under speed fault and !hi. will cau.e
the over speed LED to flash.
The OBD (On Board Diagnostic) will also show these faults.
~ WESTERBEKE
Engines & Generators
9