Generac Power Systems 53187 - Manual (Page 109)

PARTS
ENGINE ELECTRICAL SYSTEM
1
SECTION 5.1
INTRODUCTION TO DC CONTROL SYSTEMS
Operating Diagram- Type 2 DC Control System
Operation of the Type 2 DC control system may be
briefly described as follows:
SHUT DOWN:
Battery voltage Is available to the engine control
circuit board via Wire 13, a 10 amp circuit breaker
(CB3), a 14 amp fuse (FI), and Wire 15. However,
circuit board action holds this power circuit open.
CRANKING;
When the start/stop switch is set to “Start", Wire 17
from Terminal 3 of the circuit board is connected to
ground. The circuit board responds by initiating the
following actions:
□ The circuit board delivers battery voltage through the
starter contactor coil and to ground, via Wires 56 and
0. The starter contactor energizes, its contacts close,
and battery voltage is delivered to the starter (S). The
engine cranks.
□ Circuit board action delivers battery voltage to the
Wire 14 circuit, and to the hourmeter (HM), the fuel
pump (FP), and the fuel solenoid (FS). The hour-
meter runs. Fuel is delivered to the diesel fuel system
and the engine can start and run.
□ Battery voltage is delivered to the field boost circuit,
via Wire 9.
RUNNING;
□ When the engine starts, the start/stop switch is re­
leased, to open the Wire 17 circuit.
□ Circuit board action opens the Wire 56 circuit and
cranking ends.
□ Circuit board keeps the Wire 14 circuit open. The fuel
solenoid (FS) and fuel pump (FP) remain energized
and the engine continues to run.
SHUTDOWN;
Setting the start/stop switch to “Stop* connects the
Wire 18 circuit to ground. Circuit board action then
opens the Wire 14 circuit. The fuel pump (FP) and fuel
solenoid (FS) de-energize and engine shuts down.
CBS ■ 10 AMP
CIRCUrr BREAKER
FI > 14 AMP FUSE
FP • FUEL PUMP
FS ■ FUEL SOLENOID
HM ■ HOURMETER
KVYT * HIGH TEMP. SWrrCH
LOS B LOW OIL PRESSURE
SWITCH
8 B STARTER
Figure 3, Operating Diagram- Type 2 DC Control System
PAGE 5.1-3