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Sofar Solar Error Codes

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

Quickly identify problems with your Sofar Solar system and learn the correct response procedures

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Sofar Solar Inverter Models

Sofar Solar produces high-quality inverters for residential, commercial, and utility-scale solar installations. Sofar Solar inverters are known for their reliability, efficiency, and advanced monitoring capabilities. The product line includes HYD series (hybrid inverters with battery storage) and KTLX series (string inverters) with various power ratings. These diagnostic codes are applicable to the majority of Sofar Solar inverter systems. Error indicators typically manifest as error codes displayed on the inverter LCD screen, LED status lights, or in the monitoring portal. Error codes follow a three-digit numeric format (e.g., 002, 003, 005) with descriptive names (e.g., GridUVP, GridOFP, GFCI).

How to Read Error Codes

• Check inverter LCD screen for error code display
• Review LED status indicators on inverter
• Check monitoring portal for system status messages
• Note error code format (e.g., 002, 003, 005)
• Consult Sofar Solar documentation for your specific model
• Error codes are three-digit numbers with descriptive names

Sofar Solar Product Series

• HYD Series - Hybrid inverters with battery storage
• KTLX Series - String inverters for commercial use
• Single-Phase Models - Residential applications
• Three-Phase Models - Commercial and utility applications
• Monitoring Systems - Advanced system monitoring and control

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Understanding Diagnostic Codes

Sofar Solar inverter systems incorporate sophisticated diagnostic capabilities that automatically detect operational issues. When a problem is identified, the system communicates through error codes displayed on the inverter LCD screen, LED status indicators, and status messages in the monitoring portal. Error codes follow a three-digit numeric format (e.g., 002, 003, 005) with descriptive names (e.g., GridUVP, GridOFP, GFCI). This intelligent diagnostic framework enables rapid problem identification and helps determine the appropriate response. All Sofar Solar inverter series utilize continuous performance monitoring with real-time error detection. Error codes may vary slightly depending on firmware version and model. Always reference your specific model's installation manual for precise code definitions and consult with a certified Sofar Solar installer for professional diagnosis and repair.

Grid Voltage and Frequency Errors

Problems with AC grid voltage and frequency.

Code	Meaning	Possible Causes	Solutions
002	GridUVP - Grid voltage too low	•Utility grid voltage too low •Grid voltage fluctuations •Grid instability •Voltage drop in distribution •AC protection switch issue •AC wiring problem	If alarm occurs occasionally, cause may be abnormal state of utility grid Inverter will automatically return to normal operation when grid state returns to normal If alarm occurs frequently, check if grid voltage/frequency is within allowable range If within range, check AC protection switch and AC wiring of inverter Contact utility company to report voltage issues Wait for grid voltage to return to normal range Contact installer if voltage issues persist
009	GridOVPInstant1 - Transient grid voltage overvoltage 1	•Transient grid voltage spike •Grid voltage surge •Lightning strike on grid •Grid instability	If alarm occurs occasionally, cause may be abnormal state of utility grid Inverter will automatically return to normal operation when grid state returns to normal If alarm occurs frequently, check if grid voltage/frequency is within allowable range If within range, check AC protection switch and AC wiring of inverter Contact utility company if transient overvoltages persist
010	GridOVPInstant2 - Transient grid voltage overvoltage 2	•Transient grid voltage spike •Grid voltage surge •Lightning strike on grid •Grid instability	If alarm occurs occasionally, cause may be abnormal state of utility grid Inverter will automatically return to normal operation when grid state returns to normal If alarm occurs frequently, check if grid voltage/frequency is within allowable range If within range, check AC protection switch and AC wiring of inverter Contact utility company if transient overvoltages persist
014	VGridUnbalance - Grid voltage unbalance	•Three-phase voltage imbalance •Grid instability •Phase loss •Unbalanced load on grid	Check three-phase voltage balance Verify all three phases are connected Check for phase loss Contact utility company if voltage unbalance persists Professional diagnosis may be required

Grid Frequency Errors

Problems with AC grid frequency.

Code	Meaning	Possible Causes	Solutions
003	GridOFP - Grid frequency too high	•Grid frequency too high •Grid instability •Utility frequency regulation issue	If alarm occurs occasionally, cause may be abnormal state of utility grid Inverter will automatically return to normal operation when grid state returns to normal If alarm occurs frequently, check if grid voltage/frequency is within allowable range If within range, check AC protection switch and AC wiring of inverter Contact utility company to report frequency issues Wait for grid frequency to return to normal range
004	GridUFP - Grid frequency too low	•Grid frequency too low •Grid instability •Utility frequency regulation issue	If alarm occurs occasionally, cause may be abnormal state of utility grid Inverter will automatically return to normal operation when grid state returns to normal If alarm occurs frequently, check if grid voltage/frequency is within allowable range If within range, check AC protection switch and AC wiring of inverter Contact utility company to report frequency issues Wait for grid frequency to return to normal range

Ground Fault and Leakage Current Errors

Problems with ground fault detection and leakage current.

Code	Meaning	Possible Causes	Solutions
005	GFCI - Ground fault current interruption error	•Ground fault detected •Leakage current too high •GFCI device fault •Ground fault in system	Check inverter and wiring Inspect for ground faults Test leakage current Check GFCI device operation If error persists, contact installer Professional diagnosis required
021	GFCIDeviceFault(DC) - Leakage current sampling error (DC)	•DC leakage current sampling fault •GFCI device DC fault •Sampling circuit issue	Check GFCI device Verify DC leakage current sampling If error persists, contact installer Professional diagnosis required
029	ConsistentFault_GFCI - Leakage current consistency error	•Leakage current consistency fault •GFCI consistency error •Measurement inconsistency	Check GFCI consistency Verify leakage current measurements If error persists, contact installer Professional diagnosis required

Grid Protection and Islanding Errors

Problems with grid protection functions and islanding detection.

Code	Meaning	Possible Causes	Solutions
006	OVRT fault - OVRT function fault	•Overvoltage ride-through function fault •OVRT circuit issue •Protection function malfunction	Check OVRT function If error persists, contact installer Professional diagnosis required
007	LVRT fault - LVRT function fault	•Low voltage ride-through function fault •LVRT circuit issue •Protection function malfunction	Check LVRT function If error persists, contact installer Professional diagnosis required
008	IslandFault - Islanding protection fault	•Islanding protection fault •Islanding detection circuit issue •Protection function malfunction	Check islanding protection function If error persists, contact installer Professional diagnosis required
011	VGridLineFault - Grid voltage line fault	•Grid voltage line disturbance •Grid voltage fault •Line fault detection	Check grid voltage Verify grid connection If error persists, contact installer Professional diagnosis may be required
013	RefluxFault - Reflux protection fault	•Reflux protection fault •Power reflux detection issue •Protection function malfunction	Check reflux protection function If error persists, contact installer Professional diagnosis required

Hardware Sampling and Measurement Errors

Problems with hardware sampling and measurement circuits.

Code	Meaning	Possible Causes	Solutions
017	HwADFaultIGrid - Grid current sampling error	•Grid current sampling fault •Current sensor issue •ADC circuit fault	Check grid current sampling Verify current sensor operation If error persists, contact installer Professional diagnosis required
018	HwADFaultDCI - DC component of grid current sampling error	•DC component sampling fault •Current measurement issue •ADC circuit fault	Check DC component sampling Verify current measurement If error persists, contact installer Professional diagnosis required
019	HwADFaultVGrid(DC) - Grid voltage sampling error (DC)	•Grid voltage DC sampling fault •Voltage sensor issue •ADC circuit fault	Check grid voltage DC sampling Verify voltage sensor operation If error persists, contact installer Professional diagnosis required
020	HwADFaultVGrid(AC) - Grid voltage sampling error (AC)	•Grid voltage AC sampling fault •Voltage sensor issue •ADC circuit fault	Check grid voltage AC sampling Verify voltage sensor operation If error persists, contact installer Professional diagnosis required
022	HwADErrDCI(AC) - DC component of grid current sampling error (AC)	•DC component AC sampling fault •Current measurement issue •ADC circuit fault	Check DC component AC sampling Verify current measurement If error persists, contact installer Professional diagnosis required
023	HwADErrVGrid(DC) - Grid voltage sampling error (DC)	•Grid voltage DC sampling error •Voltage sensor issue •ADC circuit fault	Check grid voltage DC sampling Verify voltage sensor operation If error persists, contact installer Professional diagnosis required
024	HwADErrVGrid(AC) - Grid voltage sampling error (AC)	•Grid voltage AC sampling error •Voltage sensor issue •ADC circuit fault	Check grid voltage AC sampling Verify voltage sensor operation If error persists, contact installer Professional diagnosis required
025	HwADErrDCI(DC) - DCI sampling error (DC)	•DCI DC sampling error •Current measurement issue •ADC circuit fault	Check DCI DC sampling Verify current measurement If error persists, contact installer Professional diagnosis required
026	HwADErrIdcBranch - DC branch current sampling error	•DC branch current sampling error •Current sensor issue •ADC circuit fault	Check DC branch current sampling Verify current sensor operation If error persists, contact installer Professional diagnosis required

PV System and Isolation Errors

Problems with PV system and isolation.

Code	Meaning	Possible Causes	Solutions
027	PVLowImpedance - PV impedance to PE too low	•PV isolation impedance too low •Ground fault in PV system •PV module insulation problem •Isolation degradation	Check PV isolation impedance Test PV system for ground faults Inspect PV module insulation Check DC wiring for damage If error persists, contact installer Professional diagnosis required This is a serious safety condition

Communication and System Errors

Problems with internal communication and system functions.

Code	Meaning	Possible Causes	Solutions
030	ConsistentFault_Vgrid - Grid voltage consistency error	•Grid voltage consistency fault •Voltage measurement inconsistency •Sensor mismatch	Check grid voltage consistency Verify voltage measurements If error persists, contact installer Professional diagnosis required
031	ConsistentDCI - DCI consistency error	•DCI consistency fault •Current measurement inconsistency •Sensor mismatch	Check DCI consistency Verify current measurements If error persists, contact installer Professional diagnosis required
033	SpiCommFault(DC) - SPI communication error (DC)	•SPI communication fault in DC circuit •Communication bus issue •DC control board communication problem	Check SPI communication in DC circuit Verify DC control board connections If error persists, contact installer Professional diagnosis required
034	SpiCommFault(AC) - SPI communication error (AC)	•SPI communication fault in AC circuit •Communication bus issue •AC control board communication problem	Check SPI communication in AC circuit Verify AC control board connections If error persists, contact installer Professional diagnosis required
035	SChip_Fault - Chip fault (DC)	•DC control chip fault •DC control board issue •Component failure	Check DC control chip If error persists, contact installer Professional diagnosis required Component replacement may be necessary
036	MChip_Fault - Chip fault (AC)	•AC control chip fault •AC control board issue •Component failure	Check AC control chip If error persists, contact installer Professional diagnosis required Component replacement may be necessary
037	HwAuxPowerFault - Auxiliary power fault	•Auxiliary power supply failure •Internal power supply issue •Control board power problem	Check auxiliary power supply Verify power connections If error persists, contact installer Professional diagnosis required Power supply replacement may be necessary
038	InvSoftStartFail - Inverter soft start failed	•Inverter soft start failure •Startup circuit issue •Control circuit problem	Check inverter soft start function Verify startup circuit If error persists, contact installer Professional diagnosis required

Arc Fault and PV System Errors

Problems with arc fault detection and PV system monitoring.

Code	Meaning	Possible Causes	Solutions
028	PIDAbnormalOut - PID abnormal output	•PID control abnormal output •Control system issue •Regulation problem	Check PID control function If error persists, contact installer Professional diagnosis required
039	ArcShutdownAlarm - Arc protection shutdown alarm	•Arc fault detected •Arc protection activated •DC arc in system •Loose connections	This is a critical safety condition Do not attempt to restart Check DC connections for arcs Inspect all DC connections for looseness Check DC wiring for damage Contact installer immediately Professional inspection required before restart
040	LowLightChkFail - No detection of weak sunlight	•Low light detection failure •Light sensor issue •Detection circuit problem	Check low light detection function Verify light sensor operation If error persists, contact installer Professional diagnosis required

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Critical Safety Notice

Do not attempt DIY repairs on your Sofar 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: 005 (GFCI), 027 (PVLowImpedance), 039 (ArcShutdownAlarm), and other safety-related errors. Upon encountering these codes, immediately shut down the system if safe to do so and contact a certified Sofar Solar installer without delay.

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

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Maintenance Guidelines

Scheduled Service Requirements

✓Professional inspection and service annually by certified Sofar Solar 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 monitoring portal
✓Check inverter status and LCD screen monthly
✓For hybrid systems, monitor battery status and health

Proactive Maintenance Strategies

✓Keep panels clean to maximize energy production
✓Trim trees and vegetation to prevent shading
✓Inspect DC wiring and connections for damage or corrosion
✓Monitor production trends for early problem detection
✓Ensure adequate ventilation around inverter
✓Review system alerts and error codes promptly
✓Regularly check AC protection switch and wiring

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Frequently Asked Questions

What does error code 002 (GridUVP) mean?

002 indicates grid voltage is too low. If the alarm occurs occasionally, the cause may be an abnormal state of the utility grid. The inverter will automatically return to normal operation when the grid state returns to normal. If the alarm occurs frequently, check if grid voltage/frequency is within the allowable range. If within range, check the AC protection switch and AC wiring of the inverter.

What should I do if I see error code 005 (GFCI)?

005 indicates a ground fault current interruption error. Check the inverter and wiring, inspect for ground faults, and test leakage current. Check GFCI device operation. If the error persists, contact your installer. Professional diagnosis is required.

What does error code 027 (PVLowImpedance) mean?

027 indicates PV impedance to PE (protective earth) is too low. This is a serious safety condition. Check PV isolation impedance, test PV system for ground faults, inspect PV module insulation, and check DC wiring for damage. If the error persists, contact your installer immediately. Professional diagnosis is required.

What should I do if I see error code 039 (ArcShutdownAlarm)?

039 indicates arc protection shutdown alarm. This is a critical safety condition. Do not attempt to restart. Check DC connections for arcs, inspect all DC connections for looseness, and check DC wiring for damage. Contact your installer immediately. Professional inspection is required before restart.

How do I check error codes on my Sofar Solar inverter?

Error codes can be viewed on the inverter LCD screen, through LED status indicators on the inverter, or in the monitoring portal. Check the LCD display for error messages (typically three-digit numbers like 002, 003, 005), observe the LED status lights, and log into your monitoring account to view system status and error history.

What does error code 003 (GridOFP) or 004 (GridUFP) mean?

003 indicates grid frequency is too high, and 004 indicates grid frequency is too low. If the alarm occurs occasionally, the cause may be an abnormal state of the utility grid. The inverter will automatically return to normal operation when the grid state returns to normal. If alarms occur frequently, check if grid voltage/frequency is within the allowable range.

Can I reset error codes by restarting the inverter?

Some error codes (like 002, 003, 004 for grid issues) may resolve automatically when grid conditions return to normal, but many codes indicate serious conditions that require professional diagnosis. Safety-related codes (GFCI, isolation faults, arc faults) should never be reset without professional inspection. Always follow the recommended solutions for each specific error code and contact a certified installer if the error persists.