TABLE OF CONTENTS
0463 395 001 © ESAB AB 2018
15AP1 Component positions............................................................. 39
20 Control module .................................................................................. 40
20AP1 Control board............................................................................ 40
20AP1 Block diagram........................................................................ 41
20AP1:1 Power supply ...................................................................... 42
20AP1:2 Fan control.......................................................................... 42
20AP1:3 CAN bus ............................................................................. 43
20AP1:4 Temperature monitoring...................................................... 45
20AP1:5 Overvoltage and undervoltage protection........................... 45
20AP1:6 Rectifier board interface ..................................................... 45
20AP1:7 Gate pulses ........................................................................ 45
20AP1:8 Output current sensors ....................................................... 46
20AP1:9 Arc voltage feedback .......................................................... 47
20AP1:10 Primary current sensor ..................................................... 49
20AP1:11 LED board interface.......................................................... 49
20AP1:12 Cooling unit interface........................................................ 49
20AP1:10 External shutdown ............................................................ 50
20AP1 Component positions............................................................. 51
20AP2 LED board ................................................................................ 51
REMOTE CONTROLS .............................................................................. 53
FAULT CODES ......................................................................................... 54
SERVICE INSTRUCTIONS....................................................................... 58
What is ESD? .......................................................................................... 58
Service aid .............................................................................................. 58
Service traps........................................................................................... 59
Disassembling and reassembling the power source.......................... 61
Checking the input rectifier ................................................................... 61
Checking the rectifier module ............................................................... 62
Checking the IGBT transistors.............................................................. 64
Checking the transistor module............................................................ 66
Checking the output diodes .................................................................. 67
Mounting components on the heat sinks............................................. 70
Soft starting ............................................................................................ 71
Checking the gate pulses from circuit board 20AP1 .......................... 72
Checking the gate pulses from circuit board 15AP1 .......................... 75
Measurements (DC-bus, output voltage and diodes) ......................... 77
Checking temperature monitoring........................................................ 78
Checking the overvoltage and undervoltage threshold values ......... 81
Calibrating the current sensor signal................................................... 82
MIG power source, calibration of the arc voltage feedback............... 83
MMA power sources, calibration of the arc voltage feedback ........... 85