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Fault route · WSM-315 TIG

WSM-315 no HF / no arc fault routing

Use this workflow when a WSM-315 TIG welder powers on but fails to start correctly: no gas, gas but no HF, HF but no welding current, foot pedal does not start, or current control behaves incorrectly. Diagnose by the first missing action in the start sequence.

Main control-board role

This page is for the main WSM-315 control board

Use this page when the repair question involves the board that coordinates torch input, gas timing, HF command, current command, feedback and protection. It is not the same as the front control panel or the panel PCB.

Which WSM-315 panel/control page should you use?

These pages are intentionally split. The control-panel page explains front-panel behavior and settings; the panel-board page covers PCB/connectors; the control-board page covers the main signal router between torch, gas, HF, current command, feedback and protection.

Control panel behaviorUse for knobs, mode behavior, upslope/down-slope, crater/end current, timing settings and service-code interpretation. Panel board PCBUse for panel PCB, front-panel connector, potentiometer/switch signals, indicators and board-level evidence. Main control boardUse for torch input, gas timing, HF command, current command, feedback and protection routing. No HF / no arc routeUse when starting from a field symptom such as gas-only, no HF, no main current or pedal no response.

Start from the first missing action

First missing actionStart hereThen check
No gas, no HF, no outputTorch/pedal input, 24V/control rail, mode selectionPanel board connector, control-board start input and gas relay output.
Gas works, no HFHF enable signal and HF board relay pathHF relay coil/contact, transformer, discharge path and HF cable.
HF works, no main arcMain output enable and current-feedback pathDrive enable, inverter output, secondary rectifier, work clamp and torch path.
Foot pedal no responseRemote contactor and remote current linesPedal pot, remote switch, panel connector and control-board remote input.
Protection light onThermal, feedback and output-stage protectionThermal switch, current feedback, power-stage short and auxiliary rails.
Post-flow wrongPanel setting and gas timing logicGas solenoid output, timing network and control-board release path.

Diagnostic route

1. Mode and triggerConfirm TIG mode, 2T/4T, local/remote and torch/pedal switch input.
2. Gas outputCheck solenoid command and actual gas flow.
3. HF enableCheck whether HF board receives a timed command.
4. Main outputCheck drive enable and output path after HF starts.
5. Feedback/cutoffCheck current feedback and HF cutoff after arc transfer.
6. Panel settingsCheck current, pulse, post-flow, down-slope and remote command.

Most useful bench note

Write down exactly what happens after torch press: gas click, gas flow, HF sound, output voltage/current, protection lamp and post-flow. That sequence usually points to the correct board faster than random component replacement.

Related WSM-315 TIG control repair references

Use these links to move between symptom diagnosis, board-level evidence, circuit paths and component or chip checks for the same repair family.

Diagnostic routes

Boards and circuit paths

Components and chips

  • No dedicated page yet.