This is the complete fault table for the DEYE SUN SG01HP3/SG02HP3 Hybrid Inverter family — 69 codes shared by 17 model numbers, transcribed from the official manual. On DEYE units, a fault code means the unit has cut its output and the red LED stays solid; a warning flashes the red LED while the unit keeps running.
Last checked against the official manuals on July 11, 2026.
DC_Inversed_Failure - the PV DC input is connected with reversed polarity.
CauseThe PV input positive and negative cables are connected in reverse.
Recommended fixCheck the PV input polarity.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
DC_Insulation_Failure - the insulation of the PV input to ground is abnormal.
CauseThe PV array is not properly grounded, or the impedance of the PV to ground is abnormal.
Recommended fixCheck whether the PV is grounded; then check whether the impedance of the PV to ground is normal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
GFDI_Failure - the ground fault detector/interrupter has detected a fault on the PV side.
CauseThe PV modules are not grounded, or the PV-to-ground impedance is abnormal and leakage current is present.
Recommended fix1. Check whether the PV modules are grounded. 2. Check whether the impedance of the PV to ground is normal and whether there is leakage current.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
GFDI_Ground_Failure - grounding fault detected by the ground fault detector/interrupter.
CauseThe PV array is not grounded.
Recommended fixCheck whether the PV is grounded.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
EEPROM_Read_Failure - the controller failed to read data from the EEPROM memory.
CauseThe inverter control board could not read its stored settings from the EEPROM memory.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
EEPROM_Write_Failure - the controller failed to write data to the EEPROM memory.
CauseThe inverter control board could not write settings to the EEPROM memory.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
DCDC1_START_Failure - the BUS voltage cannot be reached by PV or battery.
CauseDC/DC converter 1 failed to start because the internal BUS voltage could not be built up from the PV or battery input.
Recommended fixSwitch off the DC switches and restart the inverter.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
DCDC2_START_Failure - the BUS voltage cannot be reached by PV or battery.
CauseDC/DC converter 2 failed to start because the internal BUS voltage could not be built up from the PV or battery input.
Recommended fixSwitch off the DC switches and restart the inverter.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
IGBT_Failure - a fault was detected in the IGBT power module.
CauseThe IGBT power module of the inverter reported a fault.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
AuxPowerBoard_Failure - the auxiliary power supply board reported a fault.
CauseThe auxiliary power supply board is faulty; this can also be reported when the inverter's power switch is not turned on.
Recommended fix1. First check whether the inverter switch is on. 2. Restart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
AC_MainContactor_Failure - the main AC contactor (relay) reported a fault.
CauseThe main AC contactor of the inverter failed its check or did not switch correctly.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
AC_SlaveContactor_Failure - the slave AC contactor (relay) reported a fault.
CauseThe slave AC contactor of the inverter failed its check or did not switch correctly.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
Working_Mode_Change - the inverter's working mode has been changed.
CauseThe grid type or frequency setting has been changed, the battery mode has been changed to 'No battery' mode, or (on some old firmware versions) the system's work mode has been changed.
Recommended fixGenerally this error disappears automatically. if it remains the same, turn off the DC and AC switches for one minute, then turn on the DC and AC switches.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
DC_OverCurr_Failure - overcurrent detected on the DC side.
CauseThe DC-side current exceeded the protection limit.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
AC_OverCurr_SW_Failure - AC side overcurrent fault detected by software.
CauseThe AC-side current exceeded the software protection limit, typically because the backup load power and common load power are beyond the allowed range.
Recommended fix1. Check whether the backup load power and common load power are within the range. 2. Restart and check whether it is normal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
GFCI_Failure - leakage (residual) current fault.
CauseThe leakage current to ground exceeded the limit, usually due to a PV-side cable ground connection problem.
Recommended fix1. Check the PV side cable ground connection. 2. Restart the system 2-3 times.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
Tz_PV_OverCurr_Fault - transient overcurrent detected on the PV input.
CauseThe PV input current spiked beyond the limit, typically because the PV connection is unstable.
Recommended fix1. Check the PV connection and whether the PV is unstable. 2. Restart the inverter 3 times.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
Tz_AC_OverCurr_Fault - AC side overcurrent fault detected by hardware.
CauseThe AC-side current exceeded the hardware protection limit, typically because the backup load power and common load power are beyond the allowed range.
Recommended fix1. Check whether the backup load power and common load power are within the range. 2. Restart and check whether it is normal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
Tz_Integ_Fault - integrated transient hardware protection fault.
CauseAn internal combined (integrated) transient hardware protection was triggered.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 49sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 50sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 50
Tz_Dc_OverCurr_Fault - DC side overcurrent fault detected by hardware.
CauseThe DC-side current exceeded the hardware protection limit; a PV module or battery connection problem, or starting the inverter under a high power load in off-grid mode, can trigger it.
Recommended fix1. Check the PV module connection and battery connection. 2. In off-grid mode, starting the inverter under a high power load may report F20 - reduce the connected load power. 3. if it remains the same, turn off the DC and AC switches for one minute, then turn on the DC and AC switches.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
Tz_HV_Overcurr_Fault - overcurrent on the internal high-voltage BUS.
CauseThe DC BUS current exceeded the limit, typically because the PV input current or the battery current setting is too high.
Recommended fix1. Check the PV input current and the battery current setting. 2. Restart the system 2~3 times.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
Tz_EmergStop_Fault - the inverter has been shut down remotely.
CauseA remote shutdown command was issued; the inverter is being remotely controlled.
Recommended fixThe inverter is remotely controlled - check the remote control/shutdown source and release the remote stop.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
Tz_GFCI_OC_Fault - transient overcurrent of the leakage (residual) current.
CauseThe leakage current spiked beyond the transient limit, usually due to a PV-side cable ground connection problem.
Recommended fix1. Check the PV side cable ground connection. 2. Restart the system 2~3 times.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
DC_Insulation_Fault - the PV isolation resistance is too low.
CauseThe insulation resistance between the PV array and ground is below the limit; the PV panel connections or the inverter's PE grounding may be faulty.
Recommended fix1. Check that the connection of the PV panels and the inverter is firm and correct. 2. Check whether the PE cable of the inverter is connected to ground.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
DC_Feedback_Fault - abnormal DC feedback detected.
CauseThe inverter detected abnormal DC feedback and tripped its DC feedback protection.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
BusUnbalance_Fault - the internal DC BUS voltages are unbalanced.
CauseThe load power on the 3 phases differs greatly, or there is DC leakage current.
Recommended fix1. Wait for a while and check whether it returns to normal. 2. Restart the system 2~3 times.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
DC_Insulation_Fault - internal DC insulation fault.
CauseThe inverter's DC insulation monitoring reported a fault.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
DCIOver_M1_Fault - the DC component of the output current exceeded the limit (measurement channel M1).
CauseThe DC injection (DC component) in the AC output measured on channel M1 exceeded the limit.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
Parallel_Comm_Fault - communication fault between paralleled inverters.
CauseThe parallel communication cable connection or the hybrid inverter communication address setting is incorrect; F29 also appears normally during parallel system startup until all inverters are in ON status.
Recommended fix1. When inverters are connected in parallel, check the parallel communication cable connection and the hybrid inverter communication address setting. 2. During the parallel system startup period, inverters will report F29; when all inverters are in ON status, it disappears automatically.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
AC_MainContactor_Fault - the main AC contactor reported a fault.
CauseThe main AC contactor of the inverter failed its check or did not switch correctly.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
AC_SlaveContactor_Fault - the slave AC contactor reported a fault.
CauseThe slave AC contactor failed its check; an incorrect grid orientation (wiring) can cause it.
Recommended fix1. Check whether the grid orientation is correct. 2. Restart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
DCIOver_M2_Fault - the DC component of the output current exceeded the limit (measurement channel M2).
CauseThe DC injection (DC component) in the AC output measured on channel M2 exceeded the limit.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
AC_OverCurr_Fault - overcurrent on the AC (grid) side.
CauseThe grid-side AC current is too large.
Recommended fix1. Check whether the grid current is too large. 2. Restart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
AC_Overload_Fault - the backup load exceeds the allowed power.
CauseThe load connected to the backup (Load) port exceeds the allowed power range.
Recommended fixCheck the backup load connection and make sure it is within the allowed power range.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 50sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 51sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 51
AC_NoUtility_Fault - no utility grid detected.
CauseThe utility grid is not detected - the grid is down, or the grid voltage/frequency or the grid connection is abnormal.
Recommended fixCheck the grid voltage and frequency and whether the connection of the power grid is normal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
INT_AC_OverCurr_Fault - inverter internal AC overcurrent.
CauseThe inverter's internal AC current exceeded the limit.
Recommended fixRestart the inverter.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
INT_DC_OverCurr_Fault - inverter internal DC overcurrent.
CauseThe inverter's internal DC current exceeded the limit.
Recommended fixRestart the inverter.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
Parallel_system_Stop - the parallel system has stopped.
CauseAt least one hybrid inverter in the parallel system has shut down; all hybrid inverters in the system then report the F41 fault.
Recommended fixCheck the work status of each hybrid inverter; if at least one hybrid inverter is shut down, restore it so the parallel system can resume.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
Parallel_Version_Fault - the firmware versions of the paralleled inverters do not match.
CauseThe software/firmware versions of the inverters connected in parallel are not consistent.
Recommended fix1. Check whether the inverter versions are consistent. 2. Contact us to upgrade the software version.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_UV_OverVolt_Fault - grid voltage out of range (too high).
CauseThe grid voltage is above the range given in the specification.
Recommended fix1. Check that the voltage is in the range of the specification. 2. Check whether the AC cables are firmly and correctly connected.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_UV_UnderVolt_Fault - grid voltage out of range (too low).
CauseThe grid voltage is below the range given in the specification.
Recommended fix1. Check that the voltage is in the range of the specification. 2. Check whether the AC cables are firmly and correctly connected.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_OverFreq_Fault - grid frequency out of range (too high).
CauseThe grid frequency is above the range given in the specification.
Recommended fix1. Check whether the frequency is in the range of the specification. 2. Check whether the AC cables are firmly and correctly connected.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_UnderFreq_Fault - grid frequency out of range (too low).
CauseThe grid frequency is below the range given in the specification.
Recommended fix1. Check whether the frequency is in the range of the specification. 2. Check whether the AC cables are firmly and correctly connected.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_U_GridCurr_DcHigh_Fault - the DC component of the phase-U grid current is too high.
CauseThe DC component in the grid current of phase U exceeded the limit.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
AC_V_GridCurr_DcHigh_Fault - the DC component of the phase-V grid current is too high.
CauseThe DC component in the grid current of phase V exceeded the limit.
Recommended fixRestart the inverter 3 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 51sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 52sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 52
Battery_Temp_High_Fault - the battery temperature is too high.
CauseThe battery temperature reported by the BMS is too high.
Recommended fixCheck whether the temperature data of the BMS is too high.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
DC_VoltHigh_Fault - the internal DC BUS voltage is too high.
CauseThe BUS voltage is too high because the battery voltage is too high or the PV input voltage exceeds the allowed range.
Recommended fix1. Check whether the battery voltage is too high. 2. Check the PV input voltage and make sure it is within the allowed range.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
DC_VoltLow_Fault - the internal DC BUS voltage is too low.
CauseThe BUS voltage is too low because the battery voltage is too low.
Recommended fix1. Check whether the battery voltage is too low. 2. if the battery voltage is too low, use PV or grid to charge the battery.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
BAT2_VoltHigh_Fault - the terminal voltage of battery input 2 is too high.
CauseThe voltage measured at the battery 2 terminals is above the limit.
Recommended fix1. Check whether the battery 2 terminal voltage is high. 2. Restart the inverter 2 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
BAT1_VoltHigh_Fault - the terminal voltage of battery input 1 is too high.
CauseThe voltage measured at the battery 1 terminals is above the limit.
Recommended fix1. Check whether the battery 1 terminal voltage is high. 2. Restart the inverter 2 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
BAT1_VoltLow_Fault - the terminal voltage of battery input 1 is too low.
CauseThe voltage measured at the battery 1 terminals is below the limit.
Recommended fix1. Check whether the battery 1 terminal voltage is low. 2. Restart the inverter 2 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
BAT2_VoltLow_Fault - the terminal voltage of battery input 2 is too low.
CauseThe voltage measured at the battery 2 terminals is below the limit.
Recommended fix1. Check whether the battery 2 terminal voltage is low. 2. Restart the inverter 2 times and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
Battery_Comm_Lose - communication with the battery BMS has been lost.
CauseThe communication between the hybrid inverter and the battery BMS is disconnected while the 'BMS_Err-Stop' function is active.
Recommended fixTo avoid this error, disable the 'BMS_Err-Stop' item on the LCD.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
GEN_FAULT - the generator input is abnormal.
CauseThe voltage or frequency of the generator is abnormal.
Recommended fixCheck whether the voltage and frequency of the generator are normal, and then restart.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
INVERTER_Manual_OFF - the inverter has been switched off manually.
CauseThe inverter's power switch is turned off (manual shutdown).
Recommended fixCheck whether the switch of the inverter is turned on, restart the inverter, and restore the factory settings.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
DRMs_Stop - the inverter has been stopped by a demand response (DRM) command.
CauseA Demand Response Mode (DRM) command is active and has stopped the inverter.
Recommended fixCheck whether the DRM function is active.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
ARC_Fault - a PV DC arc fault was detected.
CauseAn electric arc was detected on the PV module cabling (ARC fault detection is only for the US market).
Recommended fixCheck the PV module cable connection and clear the fault.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
Heatsink_HighTemp_Fault - the heat sink temperature is too high.
CauseThe heat sink temperature exceeded the limit; the working environment temperature may be too high.
Recommended fix1. Check whether the working environment temperature is too high. 2. Turn off the inverter for 10 minutes and restart.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 52sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 53sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 53
FAN_IN_Warn - the inverter's internal fan is operating abnormally.
CauseThe internal fan is running abnormally, or its cable connection inside the inverter is loose or faulty.
Recommended fix1. Check the operating status of the fan. 2. if the fan is running abnormally, open the cover of the inverter and check the connection of the fan.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
Grid_phase_warn - the phase sequence detected at the grid connection is abnormal.
CauseThe phase sequence connection of the power grid is incorrect, or the configured grid type does not match the actual grid.
Recommended fix1. Check the phase sequence connection of the power grid. 2. Try to change the grid type (e.g. 240/120). 3. if there is still no solution, check the wiring at the grid end.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
Meter_offline_warn - meter communication failure.
CauseCommunication between the inverter and the external energy meter has been lost, or the meter wiring is abnormal.
Recommended fixCheck whether the meter has successful communication and whether the wiring is normal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
CT_WRONG_direction_warn - a current transformer (CT) is installed in the wrong direction or location.
CauseThe arrow on the CT case does not point toward the inverter, or the CTs are installed in the wrong location.
Recommended fixCheck whether the arrow on the CT case points to the inverter, and check that the installation locations of the CTs are correct.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
CT_Notconnect_warn - a current transformer (CT) is not detected by the inverter.
CauseThe CT wires are not connected correctly or are disconnected.
Recommended fixCheck whether the wires of the CTs are connected correctly.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
FAN_OUT1_Warn - external fan 1 is operating abnormally.
CauseExternal fan 1 is not connected correctly or is not operating normally.
Recommended fixCheck whether the fan is connected correctly and operating normally.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
FAN_OUT2_Warn - external fan 2 is operating abnormally.
CauseExternal fan 2 is not connected correctly or is not operating normally.
Recommended fixCheck whether the fan is connected correctly and operating normally.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
FAN_OUT3_Warn - external fan 3 is operating abnormally.
CauseExternal fan 3 is not connected correctly or is not operating normally.
Recommended fixCheck whether the fan is connected correctly and operating normally.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
VW_activate - the volt-watt (V-W) power response has been activated by high grid-port voltage.
CauseThe grid port voltage has risen high enough to trigger the volt-watt derating response; this can be caused by high grid voltage or by an AC cable that is too thin to carry the current.
Recommended fix1. Measure whether the grid port voltage is too high. 2. Check whether the AC cable is too thin to carry the current.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
Battery_comm_warn - abnormal communication between the inverter and the battery.
CauseThe BMS connection is unstable, or the BMS data is abnormal.
Recommended fix1. Check whether the BMS connection is stable. 2. Check whether the BMS data is abnormal.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
Parallel_comm_warn - unstable communication between paralleled inverters.
CauseThe parallel communication line connection is unstable (for example, wound together with other cables), or the parallel DIP switch is not on.
Recommended fix1. Check the connection of the parallel communication line; do not wind the parallel communication line together with other cables. 2. Check whether the parallel DIP switch is on.
Source:sun-12k-sg01hp3-eu-am2-manual.pdf· page 48sun-29.9-30-35-40-50k-sg01hp3-eu-bm3-4-20260224-en-manual.pdf· page 49sun-60-70-75-80k-sg02hp3-eu-em6-20260224-en-manual.pdf· page 49
Send us the code on your screen and a DEYE technician will reply with the exact steps for your unit. Support is free for life — a first diagnosis never needs a callout.
Compiled from official DEYE user manuals. Always consult your device manual and a qualified technician before performing repairs.