Repair workflow
Welder Common Fault Routing Table: SMAW, TIG, MIG and Plasma Cutter Checks
A cross-process WelderData routing page for technician-level triage before board-level testing.
Database summary
This WelderData routing table connects common symptoms across SMAW inverter welders, single-board DC stick welders, TIG machines, SCR CO2 / MIG welders and LGK plasma cutters. It is designed as a first routing layer: identify the symptom group, separate external wiring and setup faults from internal board faults, then continue into a model-specific or circuit-specific page.
The purpose is not to replace measurement. It prevents premature board replacement by grouping visible symptoms such as no power, no output, no gas, no high-frequency start, wire-feed failure, fan fault, protection light and plasma arc-transfer failure.
Cross-process fault routing table
| Machine type | Symptom group | First routing checks |
|---|---|---|
| DC SMAW / stick inverter | No power, no fan, no output, unstable current, current not adjustable | Input power, switch, fuse, auxiliary supply, control board, output rectifier, current potentiometer and feedback path. |
| Single-board DC stick welder | Power light on but no welding output, abnormal display, protection state | Confirm the actual output voltage, check control-board power rails, output diode stage, driver section and current feedback before replacing the full board. |
| TIG welder | No HF, HF spark but no arc, gas valve does not work, gas always flows, tungsten burns | Separate torch switch, gas solenoid, HF ignition, polarity, argon supply, post-flow circuit and mode-selection faults. |
| SCR CO2 / MIG welder | No gas, no wire feed, motor runs but current not adjustable, jog not working | Check feeder cable line pattern, torch switch, solenoid, motor drive, setpoint wiring and SCR control board. |
| LGK plasma cutter | Trigger no response, air present but no HF, HF present but no cutting arc, weak cutting, fast nozzle burn | Route through torch switch, air pressure, solenoid valve, HF ignition, pilot arc, ground clamp, consumables and output-current path. |
Symptom-first checklist
No reaction at trigger
Start with trigger switch, cable, plug, auxiliary supply and protection state. Do not move to output power parts until the control input path is confirmed.
Control works but output absent
Confirm whether output is truly missing. A display or panel fault can imitate no-output if the real terminals are not measured.
Gas or air fault
For TIG and plasma machines, separate mechanical gas flow, solenoid coil, relay drive, pressure switch, regulator and timing circuit faults.
Protection light on
Check fan, heatsink, thermal switch, overcurrent feedback, duty-cycle overload and shorted power devices. Do not bypass protection to continue testing.