Guardian 4389 Repair Manual page 83

DC CONTROL
contactor (SC). When the SC energizes, its contacts close and battery power is delivered to the starter motor
(SM).The engine cranks.
• When the circuit board's run relay (K2) energizes, 12 volts DC is delivered to a fuel solenoid (FS), via Wire 14.
The fuel solenoid (FS) energizes open and fuel is available to the engine. Wire 14 also energizes the hourme-
ter for operation (if so equipped) . Wire 14 energizes the battery charge relay (BCR), which will allow the BCR
to power the battery charger.
• As the engine cranks, magnets on the engine flywheel induce a high voltage into the engine ignition modules
(IM1/IM2). A spark is produced that jumps the spark plug (SP1/SP2) gap.
• During cranking, Wire 4 supplies 2-3 VDC (8-9 VDC isolated) to the rotor for field flash.
• With ignition and fuel flow available the engine can start.
11
22
TX
225A N2
56VA
224A
225
1VA
224 N1
+
-
0 0 12VDC ACCESSORY SOCKET
15B
13
13
0 0
F2
15B
0
15A
17
23
194
13
0
239
14
0
15
17 15 SCR
56
18
0
0 0
17
15
0 0
18
C1-5
PART 4
C2-6
C2-5
N2
N1
17
F1
15
15
15 15A
15 15
15
23
194
239
14
15
13
C2-1
16 16
14
C1-1
SC FS
0 0
0
G
IM1
D
SP1
18
IM2
D
SP2
194 23 11 22
22
SW1
239
N
11
RED
SC
BATTERY
SM
12V
BLACK
CUSTOMER
SUPPLIED
G G
Figure 3. Circuit Condition - Engine Cranking
SECTION 4.2
OPERATIONAL ANALYSIS
240VAC
N1
UTILITY
N2 INPUT
12Vdc
23
TRANSFER
RELAY
194
COIL
22
N
33
120V
POWER
120V
WINDING
(STATOR)
44
CB1
11
11
N N
240V
CB3
L
N L
G G
EXTERNAL
GFCI
OUTLET
23
TR
194
CUSTOMER
CONNECTIONS
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