DC CONTROL
LIQUID COOLED
ENGINE UNITS
SECTION 4.1
DESCRIPTION AND COMPONENTS
PART 4
Page 59
• The board delivers “field boost” current to the gen-
erator rotor via Connector Pin 1 and Wire 4. Also
see Section 2.2, “Field Boost”.
• The circuit board provides automatic engine shut-
down in the event of (a) low engine Oil pressure, (b)
high engine coolant temperature, (c) low coolant
level, (d) overspeed and (e) overcrank. See Section
1.6, “Engine-Generator Protective Devices”. On
occurrence of any one or more of these engine faults,
the circuit board will turn on a fault indicator lamp.
The various functions handled by the control board
are listed in the following chart, along with appropri-
ate circuit board connector pin numbers and wire
numbers.
PIN WIRE FUNCTION (Wiring Dia. #0F5243)
2
4
Field boost to rotor (9-10 volts DC)
3
85
Engine shutdown fault line (low oil pressure,
high coolant temperature)
4
23
Grounded (-) side of transfer relay circuit
5
194
Positive (+) DC side of transfer relay circuit
6
56
+12 volts DC to control contactor for cranking
7
---
Not used
8
14
+12 volts DC to ignition coil and hourmeter
9
---
Not used
10
178
Manual start line to AUTO-OFF-MANUAL switch
11
15A
+12 volts DC with AUTO-OFF-MANUAL switch
at AUTO or MANUAL
12
239
+12 volts DC to AUTO-OFF-MANUAL switch
13
15
+12 volts DC (battery trickle charge)
14
0
Common ground
15
224
14 volts AC from control board sensing transformer
16
225
14 volts AC from control board sensing transformer
17
T2
Line-to-line AC voltage from “Load” terminal
lugs of transfer switch
18
T1
Line-to-line AC voltage from “Load” terminal lugs
of transfer switch
2
S15
Frequency (rpm) sensing from AC power winding
3
S16
Frequency (rpm) sensing from AC power winding
4
150
Engine preheat (only on diesel engine units)
5
229
Negative (-) side of optional alarm relay connec
tion. Circuit board action will complete this circuit
to ground on occurrence of a fault shutdown.
6
176
Negative (-) side of fault indicator lamp circuit.
Circuit board action will complete this circuit to
ground on occurrence of a fault shutdown.
Figure 3. Control Board Connector Terminals
CONTROL CONSOLE COMPONENTS
TERMINAL BOARD TB1:
This 20-position terminal board (Figure 4) provides a
convenient connection point for DC control system
wiring. Terminals, associated wires and their func-
tions are listed in the following chart.
TERM. WIRE
FUNCTION
0
0
Common ground
79
--
Not used on prepackaged units
13
13
Unfused battery volts (12 volts DC)
14
14
12 volts DC with engine running only- used to
turn on ignition, open a fuel solenoid and turn
on an hourmeter.
15
--
No factory connected wires (fused 12 volts
DC)- see Terminal 229.
4
4
Regulated excitation and field boost current
to rotor
229
---
Connection for remote alarm
56
56
12 volts DC when cranking only
68
68
Oil pressure sender to panel gauge
69
69
coolant temperature sender to panel gauge
85
85
Low oil pressure switch connection
86
86
High coolant temperature switch connection
150
---
For preheat on diesel engine units only
218
---
Not used on prepackaged units
219
---
Not used on prepackaged units
NOTE: For additional information on Terminal 229
see “Remote Alarm Connection” in this section.
Figure 4. Terminal Board TB1
REMOTE ALARM CONNECTION:
Terminal 229 on terminal board TB1 is a connection
point for an alarm system (not supplied). The terminal
will support any relay requiring up to a maximum of
100 milli-amps of current draw. A relay coil is con-
nected across terminals 15 and 229. A remote alarm
device is connected across the relay contacts so that,
on contacts closure, a separate power supply will turn
the alarm device on. Terminal 15 is fused battery volt-
age (12 volts DC). On occurrence of any monitored
engine fault, control board action will complete the
terminal 229 circuit to ground, to energize the relay
and turn the alarm on.
0
0
0
79
13
14
14
15A
15A
15
4
229
56
68
69
85
86
150
218
219
2
4
8
5
2
3
194
56
14
17
8
150
S
16
S
15
229
176
15A
2
3
9
15
0
224
225
T2
T1
3
4 5 6 7
8
9 10 11 12 1
3
14 15 16 17 1
8
2
3
4
5
6
Summary of Contents for 4721
Page 60: ...PART 3 Page 56 V TYPE PREPACKAGED TRANSFER SWITCHES SECTION 3 4 DIAGNOSTIC TESTS...
Page 98: ...PART 4 Page 94 DC CONTROL LIQUID COOLED ENGINE UNITS SECTION 4 4 DIAGNOSTIC TESTS...
Page 112: ...PART 9 Page 108 ELECTRICAL DATA WIRING DIAGRAM 1 5 LITER LIQUID COOLED ENGINE DRAWING 0E0343 B...
Page 115: ......
