Search

RELATIONSHIP DATABASE

Repair Map

Start with the symptom, then move through the diagnostic workflow, circuit, board or chip, model and verified repair case.

Auxiliary power / no power

Fault

Auxiliary power supply no 24V

Workflow

Welding Machine Repair Methodology for Board-Level Diagnosis

Circuit

Auxiliary power supply

Board / chip

KA3845 / UC3845 Welder Auxiliary Power Pinout and No-Start DiagnosisKA3843 / KA3845 auxiliary power boards

Model / case

ZX7-250 Welder Repair Hub: Boards, Voltages and Fault WorkflowsKA3843 Auxiliary Power: No 24V Rail

PWM / gate drive / IGBT

Fault

Welder IGBT Keeps Blowing: Six-Layer Root-Cause WorkflowControl board shutdown / no PWM

Workflow

ZX7-250 Complete H7B Repair Sequence

Circuit

ZX7-250 Gate-Drive Transformer and 3846 Driver Primary Checks

Board / chip

UC3846 Welder PWM Controller: Pin Checks and No-PWM DiagnosisSG3525A Welder PWM Controller: Pin Checks and No-PWM DiagnosisM57962AL IGBT Driver: Fault Output, Gate Voltage and Welder Repair

Model / case

ZX7-250 Welder Repair Hub: Boards, Voltages and Fault WorkflowsUC3846 Shutdown Pin Active: No PWM Output

Plasma pilot arc

Fault

Plasma Cutter No Pilot Arc: Air, HF, Pilot DC and Transfer Diagnosis

Workflow

LGK Plasma Cutter Common Fault Table: Air, HF, Pilot Arc and Cutting Output Checks

Circuit

TIG and plasma high-frequency start circuit

Board / chip

HF arc-start boards

Model / case

LGK plasma cuttersPlasma Cutter No Pilot Arc

MIG wire feed

Fault

MIG wire feed not working

Workflow

MIG / MAG Common Fault Routing

Circuit

MIG / MAG Wire-Feed and Voltage Control Logic

Board / chip

Wire feeder boardsTL494

Model / case

MIG / MAG / CO2 WeldersMIG Wire Feeder Does Not Run

TIG HF / AC-DC

Fault

TIG no high frequency

Workflow

TIG Welder Fault Index

Circuit

TIG HF Start Control: 40V Arc-Voltage Detection and 4-Second Cutoff Logic

Board / chip

HF arc-start boards

Model / case

TIG / AC-DC TIG WeldersTIG No High-Frequency Start