Circuito
MIG avance de alambre speed control
Trigger entrada, 2T/4T lógica, motor control, gas valve, braking y speed regulation.
Separate mechanical y electrical causes
MIG avance de alambre fallas often look like a placa de control problem, but many are mechanical: tight spool tension, worn drive rolls, a blocked liner o a damaged contact tip. A proper page must separate these from a nivel de placa problems such as trigger entrada, 2T/4T lógica, motor driver o brake circuit failure.
Wire-feed diagnóstico flow
Torch trigger pressed
↓
Señal de gatillo reaches placa
↓
2T/4T lógica changes state
↓
Gas valve / contactor habilitaciónd
↓
Wire-speed commy read
↓
Motor driver salida appears
↓
Motor turns
↓
Avance de alambres smoothly
a nivel de placa comprobacións
| Comprobación | Normal / valor esperado | Significado si es anormal |
|---|---|---|
| Trigger entrada | Changes when trigger pressed | Torch switch o harness issue |
| Wire-speed commy | Variable voltage o control signal | Potentiometer o reference issue |
| Motor salida | Variable DC/PWM | Driver transistor/MOSFET o relé falla |
| Brake path | Released during feed | Brake shorting motor salida |
| Gas valve salida | Enabled con trigger | Logic o supply falla |
Common causes
- Torch trigger switch o cable open.
- Wire-feed motor brushes o winding failure.
- TL494/CD4013/LM324 style control lógica falla.
- Motor driver transistor o MOSFET short/open.
- Brake circuit remains active.
- Mechanical drag in liner, spool o drive roller.