Diagnostic tool

Lamp Limiter Short Diagnosis Tool

Use this WelderData tool to organize a safe first diagnosis when a suspect inverter welder is powered through a series bulb or lamp limiter. The output is a repair-check direction, not a final component verdict.

Enter the observed test condition

Result will appear here

Select the observed condition and generate a structured next-check list.

How WelderData interprets lamp-limiter behavior

Observed behaviorRepair meaning
Bright and stays brightDo not continue full-power testing. Isolate input bridge, DC bus, IGBT / MOSFET devices, output rectifier path and auxiliary supply shorts.
Flash then dimThe bulk capacitors likely charged without a heavy continuous short. Continue staged low-voltage and rail checks.
No lamp and no responseCheck input wiring, switch, fuse, NTC, relay path and auxiliary supply startup.
PulsingPossible relay cycling, auxiliary supply restart, protection cycling or intermittent short. Record the pattern and isolate sections.

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