CIGWELD 250i Transmig, Service Manual

Page: 5 / 128

TABLE OF CONTENTS
SECTION 4:
BASIC WELDING GUIDE ................................................................................ 4-1
4.01 MIG (GMAW/FCAW) Basic Welding Technique ....................................................... 4-1
4.02 MIG (GMAW/FCAW) Welding Troubleshooting ....................................................... 4-4
4.03 Stick (MMAW) Basic Welding Technique ................................................................ 4-7
4.04 Stick (MMAW) Welding Troubleshooting .............................................................. 4-16
4.05 TIG (GTAW) Basic Welding Technique .................................................................. 4-18
4.06 TIG (GTAW) Welding Problems ............................................................................ 4-21
SECTION 5: theory of operation .............................................................................. 5-1
5.01 Theory of Operation Flow Chart .............................................................................. 5-1
SECTION 6: Trouble shooting ................................................................................ 6-1
6.01 Power Source Problems ......................................................................................... 6-1
6.02 Tools Needed for Troubleshooting and Servicing .................................................... 6-3
6.03 Checking Unit Before Applying Power .................................................................... 6-3
6.04 Routine Service and Calibration Requirements ....................................................... 6-4
6.05 Dip Switch Settings for Calibration ......................................................................... 6-7
6.06 Output Current / Amperage Calibration ................................................................... 6-8
6.07 Output Voltage Calibration .................................................................................... 6-10
6.08 Wire Speed Calibration ......................................................................................... 6-11
6.09 Case Removal ....................................................................................................... 6-14
6.10 Visually Inspect .................................................................................................... 6-14
6.11 Preliminary check of the main inverter board ....................................................... 6-15
6.12 PCB Pin Out Connections ..................................................................................... 6-18
6:13 Waveforms ........................................................................................................... 6-20
6.14
Circuit Diagram ..................................................................................................... 6-24
6.15 Cleaning the Welding Power Source ..................................................................... 6-25
6.16 Cleaning the Feed Rolls ........................................................................................ 6-26
SECTION 7:
DISASSEMBLY PROCEDURE ........................................................................... 7-1
7.01 Safety Precautions for Disassembly ....................................................................... 7-1
7.02 Front Panel (Operator Interface) Circuit Board PCB Removal ................................. 7-1
7.03 Input Power Cord and Power Switch / Circuit Breaker Removal ............................. 7-3
7.04 EMI PCB Removal................................................................................................... 7-4
7.05 MOV PCB Removal ................................................................................................. 7-4
7.06 High Speed (HS) Fan Shroud Removal .................................................................. 7-5
7.07 HS and LS Fan Removal ......................................................................................... 7-6
7.08 Drive Motor Removal .............................................................................................. 7-7
7.09 Main PCB Removal ................................................................................................. 7-8
SECTION 8: Replacement PARTS ............................................................................ 8-1
8.01 Tweco Fusion 250 Mig Torch .................................................................................. 8-1
8.02 Transmig 250
i
Power Source .................................................................................. 8-2