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Goodwe Error Codes

Expert reference guide covering all Goodwe inverter diagnostic codes with comprehensive troubleshooting procedures and professional repair guidance

Quickly identify problems with your Goodwe solar system and learn the correct response procedures

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Goodwe Inverter Models

Goodwe produces an extensive lineup of premium inverter systems for residential and commercial solar installations. The GW series represents standard inverter technology with high efficiency, while HT series models provide high-voltage solutions for larger installations. EH series offers hybrid inverters with battery integration. These diagnostic codes are applicable to the majority of Goodwe inverter systems sold in the United States. Error indicators typically manifest as numeric error codes on the inverter display, LED status indicators, and status messages in the SEMS monitoring portal.

How to Read Error Codes

• Check inverter display for error code numbers (e.g., 01, 02, 03, 07, 12, 102, 108, 120, 302)
• Review LED status indicators on inverter
• Check SEMS portal for system status messages
• Note error code format and any additional information
• Consult Goodwe documentation for your specific model

Goodwe Product Series

• GW Series - Standard high-efficiency inverters
• HT Series - High-voltage inverters for large systems
• EH Series - Hybrid inverters with battery integration
• Data Logger - System monitoring and communication
• SEMS Portal - Cloud-based monitoring platform

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Understanding Diagnostic Codes

Goodwe inverter systems incorporate sophisticated diagnostic capabilities that automatically detect operational issues. When a problem is identified, the system communicates through numeric error codes displayed on the inverter, LED status indicators, and status messages in the SEMS monitoring portal. This intelligent diagnostic framework enables rapid problem identification and helps determine the appropriate response. All Goodwe inverter series (GW, HT, EH) utilize continuous performance monitoring with real-time error detection. Error codes are typically numeric (e.g., 01, 02, 03, 07, 12, 25, 102, 108, 120, 302) that indicate specific system conditions or faults. Always reference your specific model's installation manual for precise code definitions.

Internal Communication and System Errors

Problems with internal communication and system components.

Code	Meaning	Possible Causes	Solutions
01	SPI Error - Internal communication error	•SPI communication failure •Internal bus error •Control board issue •Communication protocol error	Disconnect grid output and DC input switches Wait 5 minutes Reconnect both switches If problem is not resolved, contact your dealer or customer service This may require professional diagnosis
02	EEPROM R/W Error - Memory chip error	•EEPROM memory fault •Memory read/write error •Memory corruption •Data storage failure	Disconnect grid output and DC input switches Wait 5 minutes Reconnect both switches If problem is not resolved, contact your dealer or customer service EEPROM may need to be reprogrammed or replaced
12	LCD Communication Error - Communication error between LCD-DSP and Master-DSP	•LCD communication failure •Display communication error •Internal bus error •Control board issue	Disconnect grid output and DC input switches Wait 5 minutes Reconnect both switches If problem is not resolved, contact your dealer or customer service This may require control board replacement

Grid Connection Errors

Problems with AC grid voltage, frequency, and connection.

Code	Meaning	Possible Causes	Solutions
03	Grid Frequency Error - Grid frequency exceeds inverter limit	•Grid frequency too high •Grid frequency too low •Grid instability •Frequency fluctuations •Grid synchronization issue	Check current grid frequency Verify frequency is within allowable limits Wait for grid frequency to stabilize Inverter will automatically reconnect when frequency returns to normal Contact utility company if frequency is consistently out of range Contact installer if problem persists
102	Grid Frequency Out of Range - Grid frequency outside allowable range	•Grid frequency too high •Grid frequency too low •Grid instability •Frequency fluctuations	Check grid frequency (should be 50Hz or 60Hz depending on region) Verify frequency is within allowable limits Wait for grid frequency to stabilize Contact utility company if frequency is consistently out of range Contact installer if problem persists
108	Grid Voltage Fluctuation - Voltage fluctuations in grid	•Grid voltage instability •Voltage fluctuations •Grid regulation issue •Transformer problems	Check grid voltage stability Verify voltage is within allowable limits Wait for grid voltage to stabilize Contact utility company if voltage fluctuations persist Contact installer if problem continues
Grid Voltage Out of Range	Grid voltage outside allowable range	•Utility grid voltage too high •Utility grid voltage too low •Grid voltage fluctuations •Grid instability	Check grid voltage with multimeter Verify voltage is within allowable limits Do not attempt to override safety shutdown Contact utility company if voltage is consistently out of range Wait for grid voltage to return to normal range System will automatically reconnect when voltage stabilizes
Grid Disconnected	System has lost connection to utility grid	•Grid power outage •Main breaker tripped •Utility disconnect •Grid failure •Anti-islanding protection	Verify grid power is actually lost Check main breaker for system This is normal safety behavior during grid outage Wait for grid power to be restored System will automatically reconnect when grid is restored If grid is normal, contact installer to check grid connection

DC Voltage and Isolation Errors

Problems with DC input voltage and electrical isolation.

Code	Meaning	Possible Causes	Solutions
DC Overvoltage	DC input voltage exceeds maximum limit	•Too many modules in series •String voltage exceeds maximum •Cold weather voltage rise •Incorrect string configuration •Module mismatch	Check string voltage with multimeter Verify number of modules per string matches inverter specifications Review string configuration in installation manual Account for cold weather voltage rise in calculations Verify module specifications match system design Contact certified installer to verify string configuration
DC Undervoltage	DC input voltage below minimum operating threshold	•Too few modules in series •Shading on panels •Faulty modules •DC wiring losses •String configuration error	Check string voltage with multimeter Verify minimum number of modules per string Inspect panels for shading Check for faulty modules in string Verify DC wiring connections Review string configuration Contact certified installer if voltage remains low
120	Isolation Test Failed - Isolation test failed	•PV system isolation below threshold •Damaged module insulation •DC wiring insulation failure •Ground fault present •Moisture in connections	Do not attempt to start the system Inspect all PV modules for physical damage Check all DC connections and junction boxes Test isolation resistance (should be above minimum threshold) Check for water ingress in junction boxes Inspect DC wiring for damage or degradation Contact certified installer to perform isolation testing This is a serious safety condition
Isolation Fault	Isolation error detected between PV system and ground	•Damaged PV module insulation •Water ingress in junction boxes •Damaged DC wiring insulation •Ground fault in PV array •Faulty inverter isolation monitoring	Immediately shut down the system Do not attempt to restart until fault is resolved Inspect all PV module connections and junction boxes Check DC wiring for damage or water ingress Test isolation resistance with megohmmeter Contact certified Goodwe installer immediately This is a serious safety condition requiring professional diagnosis

Relay and Hardware Errors

Problems with relay operation and hardware components.

Code	Meaning	Possible Causes	Solutions
07	Relay Self-Test Error - Error in relay self-test	•Relay fault •Relay self-test failure •Relay stuck •Relay circuit failure	Disconnect grid output and DC input switches Wait 5 minutes Reconnect both switches If problem is not resolved, contact your dealer or customer service Relay may need to be replaced
25	Relay Self-Test Error - Error in relay self-test	•Relay fault •Relay self-test failure •Relay stuck •Relay circuit failure	Disconnect grid output and DC input switches Wait 5 minutes Reconnect both switches If problem is not resolved, contact your dealer or customer service Relay may need to be replaced

Communication and Monitoring Errors

Problems with external communication and monitoring systems.

Code	Meaning	Possible Causes	Solutions
302	Smart Meter Communication Error - Communication problem between inverter and Smart Meter	•Smart meter communication failure •Modbus communication error •Wiring issue •Meter not responding •Communication protocol error	Check communication wiring between inverter and smart meter Verify smart meter is powered and online Check Modbus communication settings Test communication connection Restart inverter if needed Contact installer if communication cannot be restored
Data Logger Communication Error	Inverter cannot communicate with data logger	•Communication wire break •Data logger offline •Network issue •Communication protocol error	Check communication wiring between inverter and data logger Verify data logger is powered and online Check network connection Restart data logger if needed Verify communication settings Contact installer if communication cannot be restored
SEMS Portal Not Accessible	SEMS monitoring portal not accessible or showing errors	•Internet connection issue •Data logger offline •Server connectivity problem •Account access issue	Check internet connection Verify data logger is online Check SEMS server status Verify account credentials Restart data logger if needed Contact Goodwe support if portal remains inaccessible

Temperature and Overheating Errors

Problems with inverter temperature and thermal protection.

Code	Meaning	Possible Causes	Solutions
Overtemperature	Inverter temperature exceeds maximum limit	•Insufficient ventilation •Direct sunlight on inverter •High ambient temperature •Blocked air vents •Faulty cooling fan	Improve ventilation around inverter Ensure inverter is not in direct sunlight Check that air vents are not blocked Verify adequate clearance around inverter Check cooling fan operation Allow inverter to cool down before restart Contact installer if temperature remains high after improving ventilation
Temperature Sensor Error	Temperature sensor fault or communication error	•Faulty temperature sensor •Sensor wiring issue •Internal sensor failure •Communication error	Check temperature sensor connections Verify sensor is functioning Contact Goodwe support for sensor diagnostics May require inverter service

Internal Inverter Errors

Problems with inverter internal systems and hardware.

Code	Meaning	Possible Causes	Solutions
Internal Inverter Error	Internal inverter fault or hardware error	•Internal inverter fault •Control board issue •Hardware failure •Component malfunction	Attempt inverter restart If error persists, contact Goodwe support Do not repeatedly restart if error continues Note error code and contact certified installer May require inverter replacement or repair
Power Stage Error	Inverter power stage fault	•Power stage failure •IGBT failure •DC/AC conversion issue •Hardware malfunction	Contact Goodwe support immediately This requires professional diagnosis Inverter may need repair or replacement Do not attempt to repair yourself

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Critical Safety Notice

Do not attempt DIY repairs on your Goodwe solar system. The majority of diagnostic codes relate to high-voltage DC and AC electrical systems, grid connection safety mechanisms, or critical safety features. Specific codes requiring immediate professional intervention include: 120 (Isolation Test Failed), Isolation Fault, and Power Stage Error. Upon encountering these codes, immediately shut down the system if safe to do so and contact a certified Goodwe installer without delay.

Professional service is mandatory—contact a licensed solar installer or reach out to Goodwe technical support for expert assistance.

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Maintenance Guidelines

Scheduled Service Requirements

✓Professional inspection and service annually by certified Goodwe installer
✓Monthly visual inspection of solar panels for damage or soiling
✓Clean panels quarterly or as needed based on local conditions
✓Monitor system performance daily through SEMS portal
✓Check inverter status and LED indicators monthly
✓Verify data logger is online and communicating

Proactive Maintenance Strategies

✓Keep panels clean to maximize energy production
✓Trim trees and vegetation to prevent shading
✓Ensure adequate ventilation around inverter
✓Monitor production trends for early problem detection
✓Keep firmware updated for latest features and fixes
✓Review system alerts and error codes promptly

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Frequently Asked Questions

What does error code 01 (SPI Error) mean?

Error code 01 indicates an internal communication error. Disconnect grid output and DC input switches, wait 5 minutes, and reconnect both switches. If the problem is not resolved, contact your dealer or customer service. This may require professional diagnosis.

What does error code 03 (Grid Frequency Error) mean?

Error code 03 indicates that the grid frequency exceeds the inverter limit. Check current grid frequency and verify it is within allowable limits. Wait for grid frequency to stabilize. The inverter will automatically reconnect when frequency returns to normal. Contact the utility company if frequency is consistently out of range.

What should I do if I see error code 120 (Isolation Test Failed)?

Error code 120 indicates that the isolation test failed. Do not attempt to start the system. Inspect all PV modules for physical damage, check all DC connections and junction boxes, test isolation resistance, and check for water ingress. This is a serious safety condition. Contact a certified installer to perform isolation testing.

What does error code 302 (Smart Meter Communication Error) mean?

Error code 302 indicates a communication problem between the inverter and Smart Meter. Check communication wiring between inverter and smart meter, verify smart meter is powered and online, check Modbus communication settings, test communication connection, and restart inverter if needed. Contact an installer if communication cannot be restored.

What should I do if I see error code 07 or 25 (Relay Self-Test Error)?

Error codes 07 and 25 indicate an error in relay self-test. Disconnect grid output and DC input switches, wait 5 minutes, and reconnect both switches. If the problem is not resolved, contact your dealer or customer service. The relay may need to be replaced.

Can I repair my Goodwe system myself?

High-voltage DC and AC electrical work must exclusively be performed by licensed professionals to ensure safety compliance. Homeowners can safely perform basic tasks like cleaning panels and monitoring the SEMS portal, but all technical repairs require certified Goodwe installers. Unauthorized work on electrical systems poses extreme danger and violates building codes.

What does error code 108 (Grid Voltage Fluctuation) mean?

Error code 108 indicates voltage fluctuations in the grid. Check grid voltage stability, verify voltage is within allowable limits, wait for grid voltage to stabilize, contact the utility company if voltage fluctuations persist, and contact an installer if the problem continues.

How often should I clean my solar panels?

Solar panels should be cleaned quarterly or as needed based on local conditions. Panels in dusty areas or areas with heavy pollen may need more frequent cleaning. Keep panels clean to maximize energy production. Inspect panels monthly for damage or excessive soiling that may require immediate cleaning.

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Summary

Proper interpretation of diagnostic codes is essential for effective Goodwe solar system troubleshooting. This comprehensive reference enables quick problem identification and guides appropriate response actions. Goodwe systems utilize numeric error codes displayed on inverter displays, LED status indicators, and status messages in the SEMS monitoring portal to indicate specific sensor and system malfunctions. GW, HT, and EH series inverters provide diagnostic information through error codes and monitoring systems for convenient diagnosis.

⚠️Complex diagnostic situations, especially those involving high-voltage DC and AC electrical systems and grid connection safety, require immediate professional evaluation. Critical codes demanding urgent response include: 120 (Isolation Test Failed), Isolation Fault, and Power Stage Error. These indicators represent serious safety hazards requiring certified Goodwe installer response. Adherence to scheduled maintenance protocols and immediate attention to diagnostic codes extends equipment service life and minimizes long-term operational costs. Note that error code formats may vary by model and firmware version—always consult your specific unit's installation and service manual for precise interpretations.