Inverter Repair & Troubleshooting

Fault diagnosis for off-grid, hybrid and grid-tied inverters, including output-stage, charging and thermal faults. Board-level guidance is published only where it can be given safely and accurately.

Scope

• ▪No output
• ▪Shutdown under load
• ▪Charging faults
• ▪Overheating
• ▪DC bus faults
• ▪Power-stage failure

Diagnosis guides

• Inverter Switches Off When Load Is Connected — Diagnosis and Repair

  Low- and high-frequency off-grid inverters, hybrid inverters and inverter-chargers on 12 V, 24 V and 48 V battery systems

  9 diagnostic steps · intermediate · qualified electrician

• Inverter Will Not Switch On — Diagnosis and Repair

  Off-grid, hybrid, grid-tied and inverter-charger units, low- and high-frequency, single- and three-phase

  9 diagnostic steps · advanced · qualified electrician

• Inverter Not Charging Batteries — Diagnosis and Repair

  Inverter-chargers, hybrid and off-grid inverters charging from utility, generator or solar, with lead-acid or lithium banks

  9 diagnostic steps · intermediate · qualified electrician

• Inverter MOSFET Failure — Diagnosis and Board-Level Repair

  MOSFET output and boost stages in off-grid, hybrid and inverter-charger units. Method is general; every device value must come from the manufacturer data for the specific part.

  8 diagnostic steps · specialist · specialist engineer

• IGBT Testing and Failure Symptoms — Inverter and Drive Power Stages

  Discrete IGBTs and IGBT modules in inverters, UPS power stages and variable-speed drives. Method is general; every device parameter must come from the manufacturer data for the specific part.

  8 diagnostic steps · specialist · specialist engineer

• Solar Inverter DC Bus Fault — Over-Voltage, Under-Voltage and Isolation

  Grid-tied, hybrid and off-grid solar inverters with MPPT PV inputs, single- and three-phase

  8 diagnostic steps · advanced · qualified electrician