Generac Power Systems 8 kW LP - Manual (Page 111)

CONTROLLER DISPLAY
Cranking Attempt #1
= 12 VDC ALWAYS PRESENT
= AC VOLTAGE
= GROUND FOR CONTROL PURPOSES
= 12 VDC DURING CRANKING ONLY
= 12 VDC DURING ENGINE RUN CONDITION
= DC FIELD EXCITATION
= 5 VDC TO LED
0
4
4
0
BA
6
11
22
6
2
2
REGULATOR
11
2
6
0
4
22
VOLTAGE
4 0
0
13
13
18
SP2
IM2
16
13
SCR
0 0
86 85
HTO LOP
18
0
13
12V
BATTERY
SCR
SM
IM1
SP1
44
11
POWER
WINDING
33
22
WINDING
POWER
STATOR
4
0
56
0
SC
820
817
818
819
819
818
817
820
L2
L1
LED BOARD
4
3
2
1
4
ACTUATOR
GOVERNOR
14
14
90
OUTPUT
GENERATOR
240 VAC
NEUTRAL
INPUT
UTILITY
240 VAC
TRANSFER
+ BATTERY
GROUND
56 0 15B 23
23
0
0
FS
BATTERY WARMER
OPTIONAL
N1
00
22
33
11
44
CB
15B
14
0
0
CS
N2 N1
2 1
N2 N1
18
13
86
85
4
3
2
1
18 17 16 15 14 13 12 10 9 11 8 6 7 4 3 5
CB - CIRCUIT BREAKER, MAIN OUTPUT
HTO - HIGH TEMPERATURE SWITCH
FS - FUEL SOLENOID
LEGEND
SCR - STARTER CONTROL RELAY
SC - STARTER CONTACTOR
CS - CHOKE SOLENOID
LOP - LOW OIL PRESSURE SWITCH
SM - STARTER MOTOR
BA - BRUSH ASSEMBLY
IM_ - IGNITION MODULE
SP_ - SPARK PLUG
0
J3
J1
PRINTED CIRCUIT BOARD
TO
PCB
7.5 AMP FUSE
SELF RESETTING FUSE
CONTROLLER
J2
Page 109
sEctioN 4.2
oPEratioNal aNalYsis
Figure 3. circuit condition - engine cranking
• Printed circuit board action delivers 12 volts DC to the fuel solenoids (FS1 & FS2), via Wire 14. The fuel solenoids
energize open and fuel is available to the engine. Wire 14 supplies power to the choke solenoid (CS). Circuit board
action grounds Wire 90, energizing the choke solenoid cyclically during cranking and continuously while running.
• As the engine cranks, magnets on the engine flywheel induce a high voltage into the engine ignition magnetos
(IM1/IM2). A spark is produced that jumps the spark plug (SP1/SP2) gap.
• During cranking, Wire 4 supplies 3-5 VDC (9-10 VDC isolated) to the rotor for field flash.
• With ignition and fuel flow available the engine can start.
DC CONTROL Part 4