CONTROL PANEL (TYPE 3)
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 (I), 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 1, 2 and 6 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 (2) is open and
contact (3) 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
(3) is closed.
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