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Fault route · WSE AC/DC TIG

WSE AC/DC TIG secondary inverter fault routing

Use this workflow when a WSE AC/DC TIG welder welds in DC but fails in AC mode, outputs only one polarity, ignores balance control, trips in AC, or repeatedly damages secondary inverter devices. The route separates panel command, secondary driver, secondary inverter and output feedback evidence.

Relationship map

This page is not the same as the dedicated driver-board page

This page explains the relationship between the secondary inverter stage, secondary driver board, AC/DC command, auxiliary supply, rectifier/output path and feedback. For board-level gate-drive checks, use the dedicated secondary driver board page. For polarity-switching power devices, use the secondary inverter board page.

Which WSE AC/DC TIG page should you use?

These pages are intentionally separate. Use the relationship map for system-level orientation, the driver-board page for gate-drive evidence, the inverter-board page for AC polarity power switching, and the diagnostic route when starting from a field symptom.

Relationship mapExplains how AC/DC command, auxiliary supply, secondary driver, secondary inverter and feedback work together. Secondary driver boardUse for isolated driver supply, gate-pair outputs, dead-time, interlock and one-sided gate-drive faults. Secondary inverter boardUse for AC polarity switching devices, balance behavior, AC-only failure and secondary power-stage checks. AC/DC fault routeUse when DC mode works but AC fails, AC output is one-sided, or secondary devices fail repeatedly.

Start from mode comparison

Mode resultMeaningFirst area
DC mode welds normally, AC mode failsMain inverter likely works; AC secondary path is suspect.AC/DC panel command, secondary driver, secondary inverter board.
Both DC and AC failNot only a secondary inverter issue.Main inverter, DC bus, output path, protection, feedback.
AC output only one directionOne side of secondary inverter/driver may be missing.Gate-pair drive and secondary power devices.
AC balance has no effectBalance command or waveform timing path may be missing.Panel balance pot, control-board signal, secondary driver timing.
AC trips breaker or blows devicesShoot-through, failed driver, shorted devices or wrong dead-time.Secondary driver before replacing output devices.

Diagnostic sequence

1. Verify DC modeConfirm main inverter can weld in DC before isolating AC secondary path.
2. Check AC commandAC/DC switch and panel command must reach control/driver path.
3. Check driver supplySecondary driver needs stable auxiliary/isolated supply.
4. Check gate pairsComplementary gate signals should exist without overlap.
5. Check power devicesInspect secondary inverter devices, snubbers and output connections.
6. Check feedbackOutput feedback/cutoff may stop AC if waveform is abnormal.

Do not replace secondary devices before driver checks

Repeated secondary inverter failure usually means the driver, dead-time, snubber or command path is still abnormal. Replacing output devices without checking drive symmetry can repeat the failure.

Related WSE AC/DC TIG secondary inverter 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.