G-4
ELECTRICAL DIAGRAMS
SQUARE WAVE TIG 275
Control Board Schematic (G3358-1)
X6
10
8
9
221K
R209
50V
820p
C89
22.1K
R212
3.92K
R213
10.0K
R206
X8
3
2
1
X8
4
5
6
X5
13
12
1N4936
D45
1N4936
D46
1N4936
D44
18.2K
R190
39.2K
R189
4.75K
R208
X6
11
12
13
50V
.0047
C96
D43
50V
0.1
C93
D53
Q22
2N4401
50V
.0047
C105
10.0K
R217
1W
3.3V
DZ13
LINE_SYNC
PHASE_B
PHASE_FIRE
PHASE_A
OUTPUT_ENABLE
SW_GND
SW_GND
+15V
50KHz 75% DUTY CYCLE
50 KHz OSCILATOR
LINE SYNC
(ALL CONNECTIONS ARE SINGLE POINT)
GATE SCR 4
GATE SCR 2
PHASE FIRE OR
850uS PULSE WIDTH LIMIT
PHASE FIRE
MIN PHASE
SCR DRIVING CIRCUIT
475
R320
X6
3
2
1
+15V
3.32K
R203
50V
0.1
C233
50V
0.1
C240
MC68HC705
X12
28
14
50V
0.1
C92
50V
2700p
C231
1/4W
UNLESS OTHERWISE SPECIFIED)
+15V
(
UNLESS OTHERWISE SPECIFIED)
ELECTRICAL SYMBOLS PER E1537
MFD
4093B
X6
7
14
50V
0.1
C230
4.7
35V
C229
50V
0.1
C275
4066B
X17
14
7
4066B
X16
14
7
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
GENERAL INFORMATION
4066B
X14
14
7
CAPACITORS =
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
NOTES :
.022/50V
L_5V
L_GND
SW_15V
SW_GND
G3358_2BA
SHEET 1
NUMBER.
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
(UNLESS OTHERWISE SPECIFIED)
RESISTORS = Ohms (
DIODES =
1A, 400V
GND
IN
OUT
X7
D47
1000
35V
C77
50V
0.1
C16
J8
1
X8
10
8
9
600V
.05
C83
10.0K
R202
D52
1N5402
D48
1N5402
1400V
.0047
C99
10.0K
R210
J8
9
+
t
.25
R598
1N4936
D55
50V
C102
2.00K
R192
2.00K
R193
D51
1N5402
D49
1N5402
10.0K
R218
1.00K
R589
1W
5.1V
DZ14
1.00K
R34
1.00K
R452
C60
D42
100
50V
C82
D50
1N5402
+15V
50V
.0047
C94
X8
11
12
13
33.2K
R204
22.1K
R207
PT_Vsp
SW_15V
+15V
SW_GND
18VAC
(CLEANNING)
PHASE DETECTOR
PHASE A
PHASE B
(PENETRATION)
OFF SHEET CONNECTIONS
REFER TO SHEET 2
LM224
X11
4
11
4093B
X8
7
14
50V
0.1
C97
50V
0.1
C232
LM224
X13
4
11
50V
0.1
C185
LM224
X9
4
11
50V
0.1
C187
4066B
X10
14
7
50V
0.1
C186
X5
14
7
50V
0.1
C87
LT1014
X1
4
11
5W
2.7
R194
Q21
2N4401
J1
5
10.0
R169
10.0
R160
10.0
R161
100
R174
100V
100p
C86
Q16
2N4401
D
G
S
15A
60V
Q9
3
1
2
1W
15V
DZ9
50V
.0047
C81
100V
330p
C73
47.5
R184
10.0K
R183
10.0
R170
4.75K
R201
10.0K
R200
T2
0.2mH
5
6
SCR 1, 3
J1
2
SW_GND
SW_GND
SW_GND
47.5
R108
J1
1
50V
.0047
C47
47.5
R106
47.5
R105
47.5
R110
47.5
R107
1N4936
D22
X6
4
5
6
Q13
2N4403
47.5
R104
GATE SCR 3
GATE SCR 1
41
SUPPLY
J8: 16 PIN
J5: 14 PIN
J7A: 8 PIN
J7: 8 PIN
J4: 10 PIN
Q-
J2: 4 PIN
J1: 8 PIN
J3: 4 PIN
J6: 4 PIN
VOLTAGE NET
FRAME CONNECTION
POWER SUPPLY SOURCE POINT
EARTH GROUND CONNECTION
COMMON CONNECTION
637
99
39
17
4
OCI-
TRI-
DZ-
C-
LABELS
X-
6
LAST NO. USED
D-
R-
818
Q17
2N4403
D
G
S
15A
60V
Q8
3
1
2
10.0K
R191
10.0
R158
10.0
R168
47.5
R96
J1
4
J1
6
47.5
R97
47.5
R100
1N4936
D14
PT_Vsp
PENETRATION
SCR 2, 4
CLEANNING
SW_GND
LINE SYNC.
C17
4.7
35V
C12
33.2K
R327
X2
TL431
REF
8
1
6
1.50K
R14
+5V
L_GND
L_5V
1N4936
D54
RESISTORS MAY NOT PRESENT
33.2K
R214
50V
.0047
C98
X5
1
2
Q20
2N4401
50V
.0047
C101
1.50K
R15
20.0K
R401
162K
R404
82.5K
R403
39.2K
R402
D454
SOME OR ALL OF THESE
400V
.1
C8
68.1
R55
68.1
R84
90J
130V
TP3
68.1
R88
68.1
R86
68.1
R69
68.1
R51
68.1
R44
90J
130V
TP2
68.1
R53
68.1
R76
68.1
R81
68.1
R74
68.1
R50
68.1
R77
68.1
R85
68.1
R45
68.1
R41
68.1
R42
68.1
R52
68.1
R40
68.1
R82
400V
.1
C10
68.1
R75
68.1
R54
90J
130V
TP1
68.1
R79
68.1
R80
68.1
R83
68.1
R47
68.1
R49
68.1
R46
400V
.1
C9
68.1
R48
90J
130V
TP4
68.1
R36
68.1
R87
68.1
R43
68.1
R72
SCR SNUBBER CIRCUIT
68.1
R78
68.1
R73
68.1
R70
68.1
R71
80J
150V
TP6
68.1
R37
68.1
R39
400V
.1
C7
68.1
R38
SW_15V
SW_GND
SW_GND
SW_15V
SW_15V
10.0K
R198
100V
100p
C85
10.0
R136
Q12
2N4401
1W
15V
DZ11
10.0
R145
10.0
R159
Q15
2N4401
T2
0.2mH
1
2
1N4936
D21
T2
0.2mH
3
4
T1
0.2mH
5
6
47.5
R102
47.5
R103
47.5
R109
47.5
R101
47.5
R111
J1
3
50V
.0047
C46
50V
.0047
C45
J1
7
X5
11
10
J3
5
J3
4
J3
6
J2
3
J6
2
J2
4
J3
3
J6
1
1N4936
D35
50V
.0047
C76
10.0
R146
100
R147
100V
330p
C67
1N4936
D36
4.75K
R199
47.5
R180
T1
0.2mH
1
2
SW_15V
Q19
2N4401
T1
0.2mH
3
4
47.5
R98
50V
.0047
C44
J1
8
1N4936
D20
47.5
R99
.1
G-4
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G3358-1
7-24-98
NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.