^Fault name ^Triggering criterion ^System phenomenon ^Screening method ^
|AC overvoltage |AC side line voltage > 1.2* rated voltage for 160ms\\ OR AC side line voltage > 1.15* rated voltage for 2s\\ OR When the model is equipped with a transformer， the AC side phase voltage > 1.2* rated voltage for 160ms\\ OR When the model is equipped with a transformer ，the AC side line voltage > 1.15* rated voltage for 2s   |Warning 'AC1-10 AC overvoltage' the AC module is stopped and the history Warning record is automatically entered after the fault disappears.  |1. Check system Settings --U2 board -- yes/no should be set to 'yes';\\ 2. check the output voltage system settings whether it matches the actual transformer;\\ 3. Measure whether the AC line voltage and AC phase voltage are overvoltage |
|AC undervoltage |AC side line voltage < 0.45 * rated voltage for 160ms\\ OR AC side line voltage < 0.6* rated voltage for 1s\\ OR AC side line voltage < 0.8* rated voltage for 2s\\ OR When the model is equipped with a transformer, the AC side line voltage < 0.45* rated voltage for 160ms\\ OR When the model is equipped with a transformer, the AC side line voltage < 0.6* rated voltage for 1s\\ OR When the model is equipped with a transformer, the AC side line voltage < 0.8* rated voltage for 2s" |Warning 'AC1-10 AC undervoltage', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears. |1. Check system Settings --U2 board -- yes/no, should be set to 'yes';\\ 2. Check the output voltage system settings, whether it matches the actual transformer;\\ 3. Measure whether the AC line voltage and AC phase voltage are overvoltage;\\ 4. If both steps 1 and 2 are normal, check whether the AC voltage of the main wiring diagram interface is normal. If there is no voltage, the sampling line may be connected incorrectly. |
|AC overfrequency| AC side frequency > 52Hz for 160ms\\ OR AC side frequency > 51.5Hz for 2s| Warning 'AC1-10 AC overfrequency', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears. |1. Check system Settings --U2 board -- yes/no, should be set to 'yes';\\ 2. Check the monitoring page - whether the AC frequency is normal |
|AC underfrequency| AC side frequency < 47Hz for 160ms\\ OR AC side frequency > 49Hz for 2s |Warning 'AC1-10 AC underfrequency', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears.|1. Check system Settings --U2 board -- yes/no, should be set to 'yes';\\ 2. Check the monitoring page - whether the AC frequency is normal |
|Grid connectivity switching errors |In off-grid mode, the grid has electricity for 1s.|Warning 'AC1-10 AC grid connectivity switching errors', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears.|With the STS models\\ 1. System setting -- system parameters -- type of inverter shall be set as' micro-grid STS inverter ';\\ 2. System information -- module status --STS and U2 should be online, and the communication line from STS module to U2 board should be connected correctly;\\ Without STS models\\ When the monitoring is set to off-grid, the AC switch should be disconnected |
|AC phase-sequence reversed|The AC frequency is between [-45hz, -65hz] for 1s.|Warning 'AC1-10 AC phase-sequence reversed', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears.|Check whether the phase sequence of the AC incoming line is reversed|
|Module current asymmetric |Grid three-phase current Max - min >25% rated current & Grid three-phase current maximum > 10% rated current for 30s|Warning 'AC1-10 module current asymmetric', the AC module is stopped, triggering AC fault record and the history Warning record is automatically entered after the fault disappears." |Check whether phase is missing from AC incoming line to transformer and whether phase is missing from AC side of transformer to AC module|
|DC input overvoltage |Single-stage model:\\ Bus voltage > (topping charge voltage +8V) for 2s\\ OR Bus voltage > (topping charge voltage +28V) for 200ms\\ OR Bus voltage > 930V for 8ms\\ OR Bus voltage > 935V for 1ms\\ OR Positive bus voltage > 480V for 1ms\\ OR Negative bus voltage > 480V for 1ms\\ Two-stage model:\\ Off-grid mode, bus voltage > 880V for 2s\\ OR Bus voltage > 900V for 200ms\\ OR Bus voltage > 930V for 8ms\\ Grid-tied mode, bus voltage > 920V for 2s\\ OR Bus voltage > 940V for 200ms\\ OR Bus voltage > 930V for 8ms\\ OR Bus voltage > 935V for 1ms\\ OR Positive bus voltage > 480V for 1ms\\ OR Negative bus voltage > 480V for 1ms" |Warning 'AC1-10 DC input overvoltage', the AC module is stopped, triggering AC fault record, and the history Warning record is automatically entered after the fault disappears. |1. The topping charge voltage should be greater than the actual input DC voltage;\\ 2. Check whether the fault is caused by DC source problems |
|Emergency stop|The emergency stop input dry contact is detected as low level for 20ms| Warning 'AC10-11 emergency stop', the AC module is stopped, the AC fault record is triggered, and transmitted to the U2 board. After the fault is recovered, it can be manually cleared. After the fault disappears, the historical Warning record is automatically entered.|1, EPO is pressed;\\ 2. The EPO terminal is wired incorrectly|
|Low DC voltage |AC pre-charge mode, the fault is not detected before the AC is started;\\ Two-stage model, DC pre-charge mode, this fault is not detected before the DC is started;\\ (Single-stage DC source mode judges voltage is: float charge voltage and uncontrollable rectifier voltage + 30V maximum value)\\ (Single-stage battery mode judgs voltage is: EOD voltage and uncontrollable rectifier voltage + 30V maximum value)\\ (Two-stage optical storage integrated judgs voltage is: topping charge voltage, uncontrollable rectifier voltage + 10V maximum value)\\ (The two-stage photovoltaic bus judges the voltage is: MPPT voltage, uncontrollable rectifier voltage + 10V maximum value)\\ Bus voltage < Judgment voltage - 50V for 4s\\ OR Bus voltage < Judgment voltage - 90V for 400ms\\ OR Bus voltage < Judgment voltage - 250V for 40ms\\ OR Bus voltage < Judgment voltage - 350V for 8ms |Warning 'AC1-10 low DC voltage', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears.\\ Note: The Warning is triggered 10 times from scratch, or the Warning is continued within 1 hour. The Warning will be locked for 24 hours, the DC switch will trip, and the AC fault record will be triggered. If the voltage is restored after 24 hours of automatic power-on, the Warning will be cleared automatically. |Single-stage model, please check if the EOD voltage is set too high (EOD voltage should be <battery voltage);\\ Two-stage model, please check if the topping charge voltage is set too low (the topping charge voltage should be > battery voltage); If the above steps are correct and the DC switch is tripped, the Warning has been triggered multiple times and locked. Please check the battery discharge condition and power on again for confirmation|
|Bus overvoltage|Positive bus voltage > 470V for 8ms\\ OR Negative bus voltage >470V for 8ms|Warning 'AC1-10 bus overvoltage', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears|1. Check if the positive and negative bus calibration is corrected;\\ 2. Check whether there is any problem with the N-row connection method for multi-branch models;\\ 3. No transformer may also cause the fault;|
|Heatsink overtemperature|Module temperature > 105°C for 10s\\ OR Module temperature > 110°C for 500ms\\ OR Power port temperature > 99°C for 500ms|Warning 'AC1-10 heatsink overtemperature', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears.\\ Note: Module temperature >110 °C and power port temperature >99 °C will cause DC switch trip. |1. Check whether the module fan is faulty;2. Check whether the air inlet of the module is blocked|
|Fan fault|Fan fault input dry contact is low level for 1s|Warning 'AC1-10 fan fault', the AC module is stopped, triggering AC fault record , can be manually cleared, and the history Warning record is automatically entered after the fault disappears.Note: Module temperature >110 °C and power port temperature >99 °C will cause DC switch trip|Replace the module|
|DC relay open circuit|After the DC main relay is closed, the detection starts. The voltage difference between the two ends of the relay (bus voltage - positive bus - negative bus) > 20V, lasting for 200ms|Warning 'AC1-10 DC relay open circuit', triggering AC fault record , can be manually cleared, and the history Warning record is automatically entered after the fault disappears. |Replace the module|
|Calibration parameters abnormal |There are analog quantities that are not calibrated |Warning 'AC1-10 calibration parameter abnormal'. After the fault disappears, it will be automatically entered into the historical Warning record, which will not affect the start, and can be cleared by re-energizing after calibration|Fault clearing after calibration of analog quantity|
|Output overload|Maximum value of three-phase AC active and apparent power > 1.1 * rated voltage for 160ms\\ OR Maximum value of three-phase AC current > 1.1 * rated voltage for 160ms\\ OR DC current > 110A for 160ms|Warning 'AC1-10 output overload',  the Warning will not be stopped|AC overloaded under the off-grid; DC overload or DC output short circuit in DC source mode;IGBT short circuit|
|Fuse fault|Fuse fault input dry contact is low level for 1s|Warning 'AC1-10 fuse fault', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears,the record can be manually cleared, |Replace the fuse|
|Monitoring setting fault|After the module is powered on, the parameters of the monitoring batch are not received for 100s|Warning 'AC1-10 monitoring setting fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|1. The module binary code set by DIP switches cannot exceed the number of modules;\\ 2. The number of AC parallel units monitored and set is incorrect (should be greater than OR equal to the number of AC modules);\\ 3. Record the U2 board and monitor version number|
|DC pre-charge fault |AC pre-charge\\ During the start process (DC pre-charge relay is closed), the voltage difference across the relay (bus voltage - positive bus - negative bus ) > 45V for 60s;\\ DC pre-charge\\ During the start process (DC pre-charge relay is closed), the voltage difference across the relay (bus voltage - positive bus - negative bus) > 30V for 90s\\ OR During the start process (DC main relay is closed), the voltage difference across the relay (bus voltage - positive bus - negative bus ) > 20V for 120s|Warning 'AC1-10 DC pre-charge fault", the AC module is stopped, triggering the AC fault record, which can be manually cleared. After the fault disappears, it will automatically enter the historical Warning record and automatically clear the Warning within 24 hours|DC pre-charge relay is open circuit damaged\\ DC main relay is open circuit damaged;\\ DC pre-charge resistor is damaged;\\ IGBT open circuit or auxiliary power supply problems|
|CAN A communication fault|CAN A bus does not receive monitoring communication data for 50s|Warning 'AC1-10 CAN A communication fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears. |Check whether the module communication line is firmly connected and whether the CAN A jumper cap is correct|
|U2 communication exception 2|CAN B bus does not receive U2 board communication data for 100ms |Warning 'AC1-10 U2 communication exception 2', the history warning record is automatically entered after the fault disappears |Check whether the module communication line is firmly connected and whether the CAN B jumper cap is correct|
|AC <del>pre-charge</del> pre-charge fault|AC <del>pre-charge</del> pre-charge: during the start process (AC <del>pre-charge</del> pre-charge relay is closed), the internal bus voltage < (two-phase uncontrolled rectification voltage +5V) for 120s\\ OR During the start process (AC main relay is closed), internal bus voltage < (three-phase uncontrolled rectification voltage + 30V) for 90s;\\ DC pre-charge\\ During the start process (the DC main relay is closed), the phase lock is not completed within 10s of the grid-tied mode (the voltage across the AC relay is inconsistent), and the inverter voltage is abnormal within 10s of the off-grid mode (the amplitude is less than 10% of the rated value OR Differential between Phase and phase-locked loop are more than 10°) |Warning 'AC1-10 AC pre-charge fault', the AC module is stopped, triggering AC fault record , can be manually cleared, and the history Warning record is automatically entered after the fault disappears. |Check if the pre-charge mode is set incorrectly;\\ Check if the AC pre-charge resistor is damaged.\\ Check if the AC pre-charge relay and AC main relay are damaged|
|Output overload timeout|One or more of the inverter current/inverter power/DC current overload timeout criterion and the short circuit criterion are triggered.\\ Inverter current overload timeout criterion:\\ Module inverter current three-phase maximum > 1.5 * rated current for 120ms\\ OR Module inverter current three-phase maximum > 1.3 * rated current for 200ms\\ OR Module inverter current three-phase average > 1.25 * rated current for 200ms\\ OR Module inverter current three-phase maximum > 1.2 * rated current for 1min\\ OR Module inverter current three-phase maximum > 1.1 * rated current for 10min\\ Inverter power overload timeout criterion:\\ Module inverter power three-phase maximum > 1.5 * rated power rated for 120ms\\ OR Module inverter current three-phase maximum > 1.3 * rated current for 200ms\\ OR Module inverter current three-phase average > 1.25 * rated currentfor 200ms\\ OR Module inverter current three-phase maximum > 1.2 * rated current for 1min\\ OR Module inverter current three-phase average > 1.15 * rated current for 1min\\ OR Module inverter current three-phase maximum > 1.15 * rated current for 5min\\ OR Module inverter current three-phase maximum > 1.1 * rated current for 10min\\ DC current overload timeout criterion\\ DC current > 135A for 500ms\\ OR DC Current > 125A for 90s\\ OR DC Current > 115A for 945s\\ DC current>125A lasting 90s\\ OR DC current > 115A, lasting 945s |Warning 'AC1-10 output overload timeout', the AC module is stopped, the AC fault record is triggered, and the history Warning record is automatically entered after the fault disappears.\\ Note: the Warning will be triggered 3 times from scratch. The Warning will be locked for 1 hour, and will be cleared if there is no fault after 1 hour|Check whether the power line is short-circuited;\\ Check whether there is a calibration problem;\\ If running in off-grid mode, check whether the AC load is too large;\\ If running in grid-tied mode, check whether the AC is out of phase or short circuit|
|Output voltage abnormal |Off-grid boot operation, \\ %%|%%Inverter Voltage - Output Voltage%%|%% > 60V for 400ms\\ %%|%%Inverter Voltage - Output Voltage%%|%% > 120V for 80ms|Warning "ac1-10 output voltage abnormal", the AC module is stopped, triggering AC fault record, can be manually cleared, and the history Warning record is automatically entered after the fault disappears|
|Synchronous signal fault 1|The descending edge cannot be detected by the power frequency bus, lasting for 100ms|Warning 'AC1-10 synchronous signal fault 1', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|Check whether the module communication terminal is firmly connected, and then power on to check again;\\ replace the module|
|DSP version fault|After power on, the bootloader version does not pass the matching test |Warning 'AC1-10 DSP version fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|Re-upgrade the U1 board program with the emulator|
|Sampling zero baseline abnormal|U1 board without tooling correction|Warning 'AC1-10 sampling zero anomaly', the history Warning record is automatically entered after the fault disappears|Replace the U1 board|
|U2 communication exception 1|AC module CanA mailbox 3 did not receive U2 board communication data for 60s|Warning 'AC1-10 U2 communication exception 1', the history Warning record is automatically entered after the fault disappears|Check the monitoring page to see if the U2 board is online.\\ If the U2 board is not online, check whether the matching resistor and jumper cap are correct;\\ If the U2 board is online, check whether the software version number of the U2 board and the software version number of the U1 board are correct.\\Replace the U2 board|
|15V power fault|Auxiliary power fault input dry contact is abnormal, and it will be reported for 2s|Warning 'AC1-10 15V power fault', the AC module is stopped, the AC fault record is triggered, and the history Warning record is automatically entered after the fault disappears|Check if the auxiliary power supply voltage is normal, or replace the auxiliary power supply board|
|Grid voltage asymmetric|Off-grid mode does not judge the fault;\\ Grid-tied mode\\ AC line voltage three-phase maximum > 17% of rated voltage\\ AND AC voltage asymmetric > 4% for 10s |Warning 'AC1-10 grid voltage asymmetric', the AC module is stopped, the AC fault record is triggered, and the history Warning record is automatically entered after the fault disappears.\\ Note: The asymmetric criterion is triggered 3 times, the Warning is locked, and it is cleared after 1h without fault|Measuring whether the voltage of the three-phase grid is normal;\\ Check if the AC power line is out of phase |
|Module number code conflict fault|There are two OR more AC modules with the same binary code|Warning 'AC1-10 module repeat fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears. \\ Note: the fault is handled as the deleted module|Check if the binary code is correct|
|RS-485 communication fault| The AC module did not receive the monitoring data request for 120s|Warning 'AC1-10 485 communication fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|Check if the AC module communication terminal and monitoring communication terminal wiring are loose|
|CAN B communication fault|The communication data was not received between the AC modules for 10ms|Warning 'AC1-10 CanB communication fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|Check whether the AC module communication terminal and X2 board terminal wiring are loose.\\ Check if the matching resistor and jumper cap are correct|
|CPLD version fault|The CPLD version compatibility judgment does not pass, lasting 100ms|Warning 'AC1-10 CPLD version fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears.|Re-program DSP and CPLD with emulator|
|Hardware version fault|After power-on, it is detected that the two internal binary codes of the module are set to 10 for 100ms|Warning 'AC1-10 hardware version fault', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|The two internal binary codes of the module are set to 01|
|DC relay short circuit|Just judge when both the DC main relay and the pre-charge relay are disconnected:\\ External bus voltage > (three-phase uncontrolled rectifier voltage - 50V) AND External bus voltage - Internal bus voltage < 20V for 90s|Warning 'AC1-10 DC relay short circuit', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears, the record can be manually cleared, |Check whether the AC module DC voltage and positive and negative bus voltage calibration is correct\\ Replace the AC module|
|Bus undervoltage|(Positive bus voltage < 200V \\ OR Negative bus voltage < 200V)\\ AND The machine is started and the DC main relay is closed for 400ms |Warning 'AC1-10 bus overvoltage', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears|1. Check whether the positive and negative bus calibration is corrected;\\ 2. Check whether there is any problem with the N-row connection method for multi-branch models;\\ 3. No transformer may also cause the fault|
|Ac relay short circuit|AC pre-charge relay is not closed\\ AND AC main relay is not closed\\ AND module is not started\\ AND Inverter line voltage has at least one > 24% of rated voltage|Warning 'AC1-10 AC relay short circuit, the AC module is stopped, triggering AC fault record, can be manually cleared, and the history Warning record is automatically entered after the fault disappears|1. Check whether the internal AC relay of the module is stuck OR short-circuited, repair OR replace the module|
|Synchronous signal fault 2|The carrier bus cannot detect the descending edge for 20ms |Warning 'AC1-10 synchronous signal fault 2', the AC module is stopped, and the history Warning record is automatically entered after the fault disappears|Check whether the module communication terminal is firmly connected, and then power on to check again;\\ Replace the module|
|Microgrid battery energy is low|When DC module power supply number >0, AC module ID> module power supply number Warning shutdown\\ OR DC fault requires closing AC, AC is off-grid mode\\ OR The rack is off-grid and receives the U2 control battery voltage low shutdown command|Warning 'AC1-10 microgrid battery energy is low'，the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears. |The number of DC modules shall not be less than the number of AC modules|
|Grid phase-locking failed|In the grid-tied mode, phase lock fault (>10°)|Warning 'AC1-10 grid phase-locking failed', the AC module is stopped, triggering AC fault record , and the history Warning record is automatically entered after the fault disappears|