caso de reparación
MIG alimentador de alambre Does Not Run
Use this caso page when a MIG/NBC soldadora enciende pero the avance de alambre motor does not move after the gatillo de antorcha is pressed.
síntoma pattern
The máquina may potencia up normally, the fan may run, y the salida de soldadura section may be healthy, but the feeder motor does not rotate. In some máquinas the gas valve also fails to open; in others the gas valve clicks but the motor remains dead. That difference helps separate trigger-lógica fallas from motor-drive fallas.
First comprobacións before placa repair
| Comprobación | Valor esperado resultado | Si es anormal |
|---|---|---|
| Wire spool y feed roller | Motor can turn without mechanical lock | Remove mechanical load before judging the placa |
| Torch trigger switch | Clear open/close change at trigger connector | Broken torch cable o trigger switch falla |
| Motor connector | Motor receives DC when trigger is active | No voltage means placa/relé/driver path falla |
| Motor direct test | Motor runs from a suitable external DC supply | Dead motor, worn brushes o seized gearbox |
| 24V o control rail | Stable under trigger load | Auxiliary supply drops o feeder placa supply missing |
a nivel de placa diagnóstico path
Press gatillo de antorcha
↓
Confirm trigger signal reaches feeder placa
↓
Comprobación 2T/4T latch o lógica section
↓
Comprobación speed-control voltage from potentiometer
↓
Comprobación motor driver transistor / MOSFET / relé
↓
Verify motor voltage under load
Likely failed sections
- Open torch-trigger line o bad connector.
- Missing 24V feeder-placa supply.
- Failed relé contact feeding the motor.
- Shorted o open motor driver transistor/MOSFET.
- Bad speed potentiometer o broken reference voltage.
- Logic IC o latch falla in 2T/4T placas de control.