Component reference
SSR-10DA-H Welder Fan Control Faults
SSR faults can make smart fans run constantly, never run, or fail to switch auxiliary loads.
Component role
Digital welders may control the fan with an SSR instead of a simple switch. Separate command signal, SSR output, fan supply and fan capacitor before replacing the main board.
Repair evidence table
| Symptom | Likely direction | First check |
|---|---|---|
| Fan never stops | SSR shorted ON or control output stuck | Measure SSR output and control input state. |
| Fan never starts | SSR open, no command, no fan supply or bad fan capacitor | Confirm whether the machine expects delayed smart-fan behavior. |
| HF stuck or no HF | SSR output path depending on model | Separate SSR load from HF board and control logic. |