You may request inspection within 15 days of delivery. Quality issues not caused by human factors are covered by free repair or replacement during the warranty period. Damage caused by improper installation, wiring errors, water ingress, lightning, or other human/force-majeure causes is not covered. Return shipping costs are borne by the responsible party.

Please check: 1. Whether the battery voltage is sufficient (low voltage causes output drop); 2. Whether total load power exceeds the inverter rating; 3. Whether surge power from inductive loads (AC, fridge) is within the inverter's tolerance (typically 2× rated power); 4. Whether AC connections are secure.

An insulation fault is usually caused by poor PV-to-ground insulation. Please check: 1. Whether PV panels and cables are damp or damaged; 2. Whether DC connectors are properly waterproofed; 3. Whether PV cables are touching the metal roof. The fault usually clears once the issue is resolved. If it persists, contact a professional for inspection.

Lithium (LiFePO4) batteries offer longer cycle life (3,000-6,000 cycles vs 500-1,500), higher efficiency, smaller size, and less maintenance. Although the upfront cost is higher, they are more economical long-term. Lead-acid batteries are cheaper but shorter-lived and require regular maintenance. Choose based on budget and expected service life.

Please inspect the package upon delivery. If you find visible damage, deformation, or missing accessories, take photos/videos immediately and contact us. For confirmed shipping damage, we will arrange spare parts reshipment, unit replacement, or refund. Return shipping costs are borne by the responsible party

Please check: 1. Whether the PV panels are generating normally (MPPT voltage reading); 2. Whether the battery type setting is correct (lead-acid/lithium); 3. Whether the charging current limit is set too low; 4. Whether battery connections are secure; 5. Whether the battery is already full or in protection mode.

Inverters feature temperature-controlled automatic cooling fans that only operate when needed, running quietly most of the time. If the fan does not work at all, it may be a loose fan cable connection, a defective fan, or a PCB failure

1. Keep the installation environment well-ventilated and dry; clean the cooling fan and heatsink regularly; 2. Periodically check that terminals are tight; 3. Ensure the display shows normal data; 4. Check waterproof seals for outdoor installations before rainy seasons; 5. We recommend a professional inspection every 6-12 months.

1. Confirm the WiFi is 2.4GHz band (5GHz is not supported); 2. Check that the password is correct; 3. Check whether the inverter is set to night low-power mode—if so, it will auto-recover when DC power returns the next day; 4. Restart both the router and the inverter and try again.

The inverter LCD screen or mobile app will display a specific error code. Common faults include: grid over/under voltage, PV insulation fault, over-temperature, fan failure, etc. Please record the error code and troubleshoot according to the manual. If unresolved, contact technical support with the model and error code

Please check: 1. Whether the battery voltage is normal (not depleted); 2. Whether the battery polarity connection is correct—never reverse positive and negative; 3. Whether the DC breaker/fuse is on or blown; 4. Whether PV input is normal. If all checks pass and it still does not power on, please contact technical support.

The standard warranty is typically 2-5 years, and some premium grid-tie inverters can be extended to 10 years. The warranty period starts from the date of delivery. Non-human-caused defects are covered with free repair or parts replacement.