TABLE OF CONTENTS
0740 800 205 © ESAB AB 2016
15AP7 Soft start board ........................................................................... 56
15AP7:1 Soft start circuit........................................................................ 56
15AP7:2 Power supply for over-/ under-voltage monitoring................... 56
15AP7 Component positions.................................................................. 57
18AP1 AC control board ..........................................................................
58
18AP1:1 Output voltage monitoring ....................................................... 58
18AP1:2 Auxiliary switch commutation .................................................. 59
18AP1:3 Reset ....................................................................................... 60
18AP1:4 Fault......................................................................................... 60
18AP1:5 Temp monitoring ...................................................................... 61
18AP1:6 +24V ........................................................................................ 62
18AP1:7 Commutation switch gate control ............................................ 62
18AP1:8 Capacitor voltage monitoring................................................... 63
18AP1:9 Current block ........................................................................... 63
18AP1 Component positions.................................................................. 64
20AP1 Control board................................................................................
65
20AP1:1 Power supply ........................................................................... 66
20AP1:2 CAN 1 ...................................................................................... 68
20AP1:3 CAN 2 ...................................................................................... 69
20AP1:4 Connection to the Internal power supply board ....................... 69
20AP1:5 Over-/under voltage monitoring ............................................... 70
20AP1:6 Idle voltage .............................................................................. 70
20AP1:7 Secondary current ................................................................... 71
20AP1:8 Temp monitoring power module .............................................. 72
20AP1:9 Secondary voltage................................................................... 73
20AP1:10 Primary gate drives................................................................ 74
20AP1:11 Primary current ...................................................................... 76
20AP1:12 Temp monitoring: power board .............................................. 77
20AP1:13 Temp monitoring: primary heatsink and main transformer .... 78
20AP1:14 Output voltage monitoring AC unit......................................... 79
20AP1:15 Current block AC unit ............................................................ 80
20AP1:16 Reset signal AC unit .............................................................. 80
20AP1:17 Fault signal AC unit ............................................................... 80
20AP1:18 Temp monitoring AC unit ....................................................... 81
20AP1:19 +24V AC unit ......................................................................... 81
20AP1:20 Commutation switch gate control AC unit.............................. 81
20AP1:21 Capacitor voltage monitoring AC unit .................................... 82
20AP1:22 Arc voltage monitoring........................................................... 82
20AP1:23 Processor and miscellaneous circuits ................................... 83
20AP1 Component positions.................................................................. 85
FAULT CODES .........................................................................................
86
Fault log.....................................................................................................
86
Fault code description .............................................................................
86
SERVICE INSTRUCTIONS.......................................................................
94
What is ESD? ............................................................................................
94
Service aid ................................................................................................
94
Special tools .............................................................................................
95
Cleaning the heatsinks ............................................................................
96
Mounting components on the heat sink.................................................
96
Checking the primary rectifier bridge ....................................................
98