Falla
Soldadora conectada por error a 380V
Wrong-voltage damage path: entrada fuse, varistor, rectificador, capacitores y fuente auxiliar.
Damage pattern
When a soldadora is connected to the wrong high tensión de entrada, the damage usually starts at the entrada protección y energy-storage path. The falla can then spread into the auxiliary supply y placa de control. A máquina that only blows the fuse may still have hidden rectificador, capacitor o varistor damage.
Inspection sequence
Disconnect y discharge
↓
Inspect fuse / breaker
↓
Inspect MOV / NTC / entrada traces
↓
Test puente rectificador
↓
Inspect bulk capacitores
↓
Comprobación auxiliary PWM supply
↓
Comprobación placa de rieles de control
↓
Potencia up con current limiting
Common damaged parts
- entrada fuse o breaker.
- MOV/varistor cracked o shorted.
- NTC limiter damaged.
- puente rectificador shorted.
- Bulk electrolytic capacitores bulged o vented.
- Auxiliary supply arranque resistencia o controlador PWM damaged.
Do not simply replace the fuse
Replacing the fuse without comprobacióning the entrada puente, capacitores y fuente auxiliar etapa can cause a second failure y may destroy more expensive parts.