CONTROL PANEL (TYPE 4)
SYSTEMS OPERATION
AUTOMATIC START/STOP SYSTEM
Introduction
The automatic start stop system is normally used for
standby operation. That is. without an operator. The
generator set must start, pick up the load. operate the
load, and stop after the load is removed. An automatic
transfer switch controls the transfer of load to and from
the generator set. When normal (commercial) power
has a failure. initiating contactor (1). part of the
automatic transfer switch. closes. This will begin the
automatic start sequence. When the engine starts, the
control panel instruments will show voltage and
frequency. The automatic transfer switch will transfer
the load to the generator set when voltage and
frequency reach approximately rated value. When
normal power returns. the automatic transfer switch will
transfer the load back to normal power. Initiating
contactor (I) will open. This will begin the automatic stop
sequence. The generator set will also stop automatically
if the engine has a failure.
NOTE: For specifications on components
located on the engine, make reference to the
ENGINE SERVICE MANUAL.
Automatic Start
With engine control switch (ACS) in the AUTO
position. contacts (10) and (9) are closed. When
commercial (normal) power has a failure. remote start
initiating contact (I) closes. This makes a complete
circuit from battery (BATT) to energize run relay (RR)
and magnetic switch (MS).
When run relay (RR) is energized, contacts RR2) open
and contacts (RR1) close. (RR2) open prevents current
flow to shutoff solenoid (SS) through pressure switch
(PSW). (RR1) closed energizes dual speed switch
(DSS) and overcrank timer (OCT).
When dual speed switch (DSS) is energized, a
magnetic pickup relays engine rpm to the switch. The
dual speed switch has a crank terminate (CTS) circuit
and an overspeed (OSS) circuit.
When overcrank timer(OCT) is energized. a timer will
start. After the engine cranks for approximately 30
seconds the timer will stop. (OCT) contacts will close.
Make reference to ENGINE DOES NOT START.
When magnetic switch (MS) is energized. (MS)
contacts close and pinion solenoid (PS) is energized.
This causes (PS) contacts to close. starting motor (SM)
will crank the engine. (PSW) will close. This energizes
water temperature gauge (\WTG) and oil pressure gauge
(OPG).
Manual Start
The current flow for manual start is similar to automatic
start except engine control switch (ACS) is turned to the
MAN position. Contact (10) is open and contact (11) is
closed. It is not necessary for remote start indicating
contact (I) to close. Run relay (RR) and magnetic switch
(MS) will energize as soon as contact (11) is closed.
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