Westerbeke 12.5 BTDA - Safety Shutdown Switches and Sensors; Automatic Shutdown Switches Explained; DC Circuit Breaker Function and Reset

SAFETY SHUTDOWN SWITCHES AND SENSORS
SAFETY SHUTDOWN SWITCHES
The engine is protected by three automatic shutdown
switches. Should shutdown
occur, do not attempt to restart
without finding and correcting the cause. Refer to the
heading "Engine Stops" in the TROUBLESHOOTING
section of this manual.
The following is a description of these automatic shutdown
switches:
High Exhaust Temperature Switch
An exhaust temperature switchis located on the water
injected exhaust
elbow. Its contacts are normally closed.
If the contacts open due to a high coolant temperature, the
DCruncircuitisinterrupted and
the unit shuts down.
The switch's contact open at 260° "270°F(l27° -127°C).
The switch's contacts:elose when the temperature lowersto
approximately
225°F (l07°C).
EXHAU$1 (HIGH)
TEMPERAfURE SWITCH
Engine Coolant Temperature SWitch
A high engine coolant temperature switch located on the
thermostat housing. Its contacts are norma1ly closed. If the
contacts open
due to a high coolant temperature, the DC run
circuit is interrupted and the unit shuts down. The switch's
contact
open at approximately 210°F (99°C). The switch's
contacts close when the coolant
tem.perature.lowers to
195°F (107°C).
THERMOSTAT
ASSEMBLY
Low Oil Pressure Switch
A low oil pressure switch is located off the engine's oil
gallery adjacent to the oil filter. Its contacts are normally
open when
the engine is in a static state, this switch's sensor
monitors the engine's oil pressure. Oil pressure closes
the
contacts. Should the engine's oil pressure fall to 5-l 0 psi, the
contacts open interrupting the
DC run circuit shutting the unit
down.
OIL PRESSURE SENDOR
Engine DC Circuit Breaker
The engine's DC circuitis protected b}'~'l engine mounted
230 amp DC breaker. Should amperage in excess of 20 amps
by draw through the breaker caused by an issue with the
engine's DC circuit, it will open and shut the unit down.
Investigate the issue and then manually reset the breaker.
This is· done by pushing the red b1.1tton in.
ENGINE DC CIRCUIT .
BREAKER
The· wiring connections to ·these components are
shown in the WIRING DIAGRAMS in this manual.
/"W'JWESTERBEICE
. · E'ngfnes & Generators
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