SHUTOFF AND ALARM SYSTEMS
SYSTEMS OPERATION
open and break the circuit to fuel shutoff solenoid (9)
causing engine shutdown. However, if engine oil
pressure closes the N.O. switch in oil pressure switch
(6), current will flow through water temperature switch
(5), overspeed switch (3) and terminal five of time delay
relay to the shutoff solenoid. Current also flows to
terminal one of the time delay relay. This will immediately
open N.C. switch (8).
If the speed of the engine gets more than the setting
of the overspeed switch, N.C. switch (3) opens. This
stops current flow to the fuel shutoff solenoid and will
cause the engine to shutdown.
When the engine speed gets less than the cranking
speed setting, switch (4) opens. This stops the flow of
current to terminal two of the time delay relay. When the
engine stops, engine oil pressure will become less than
the setting of the oil pressure switch. The N.O. switch will
open and stop the flow of current to terminal one of the
time delay relay. This will start the time delay relay timer.
After 70 seconds, switch (8) will close and again let
current flow to the fuel shutoff solenoid.
NOTICE
To help prevent damage to the engine, find and
correct the problem that caused the engine to
overspeed before the engine is restarted.
After an overspeed shutdown, the overspeed switch
must be reset.
When the engine has been started and is running,
the time delay relay will open switch (8). If the engine
coolant temperature goes above the setting of water
temperature switch (5), the N.C. contacts will open. This
stops current flow through the water temperature switch
and through overspeed switch (3) to the fuel shutoff
solenoid causing engine shutdown.
When the engine speed gets less than the cranking
speed setting, switch (4) opens. This stops the flow of
current to terminal two of the time delay relay. When the
engine stops, engine oil pressure will become less than
the setting of the oil pressure switch. The N.O. switch
will open and stop the flow of current to terminal one of
the time delay relay. This will start the time delay relay
timer. After 70 seconds, switch (8) will close and again
let current flow to the fuel shutoff solenoid.
NOTICE
To help prevent damage to the engine, find and
correct the problem that caused the engine to get
too hot before the engine is restarted.
When the engine has been started and is running,
the time delay relay will close switch (8). If the engine oil
pressure gets less than the setting of oil pressure switch
(6), the N.O. switch will open. This will stop current flow
through switch (3) to the fuel shutoff solenoid causing
engine shutdown. The current flow will also stop to
terminal one of the time delay relay. When the engine
speed gets less than the cranking speed setting, switch
(4) opens. This stops the flow of current to terminal two
of the time delay relay and starts the time delay relay
timer. After 70 seconds, switch (8) will close and again
let current flow to the fuel shutoff solenoid.
NOTICE
To help prevent damage to the engine, find and
correct the cause for low engine oil pressure before
the engine is restarted.
NOTE : To help prevent discharge of the batteries when
the engine is shut off, a switch can be installed to turn off
the current to the shutoff solenoid.
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