About the Felicity FLS-ES232LC-S
The Felicity FLS-ES232LC-S is a Energy storage system unit. The 140 error codes listed below are the complete fault catalog for this device, compiled from the official Felicity user manual.
FLS-ES232LC-S
Energy storage system140 codes 36 Critical 65 Fault 39 Warning
How to use this page
Each row below shows an error code, its severity, and a brief description. Click any row to expand the full cause and the recommended fix. The severity dot tells you whether the unit will keep operating (warning), derate (fault), or trip offline (critical). For codes that require an authorized service partner, the recommended-fix block says so explicitly.
0x10A1Cell voltage accumulation overvoltage alarm in battery cluster (level 1).Warning— level 1
Cause
Vsum > 3.65V × N (N = number of battery strings).
Recommended fix
Send faults externally. Recovers when Vsum < 3.6V × N.
Source:
FLS-ES232LC-S.pdf0x10A2Cell voltage accumulation overvoltage alarm in battery cluster (level 2).Fault— level 2
Cause
Vsum > 3.7V × N.
Recommended fix
Send faults externally and limit power. Recovers when Vsum < 3.65V × N.
Source:
FLS-ES232LC-S.pdf0x10A3Cell voltage accumulation overvoltage alarm in battery cluster (level 3).Critical— level 3
Cause
Vsum > 3.8V × N.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when Vsum < 3.7V × N.
Source:
FLS-ES232LC-S.pdf0x10B1Cell voltage accumulation undervoltage alarm in battery cluster (level 1).Warning— level 1
Cause
Vsum < 2.50V × N.
Recommended fix
Send faults externally. Recovers when Vsum > 2.60V × N.
Source:
FLS-ES232LC-S.pdf0x10B2Cell voltage accumulation undervoltage alarm in battery cluster (level 2).Fault— level 2
Cause
Vsum < 2.40V × N.
Recommended fix
Send faults externally and limit power. Recovers when Vsum > 2.50V × N.
Source:
FLS-ES232LC-S.pdf0x10B3Cell voltage accumulation undervoltage alarm in battery cluster (level 3).Critical— level 3
Cause
Vsum < 2.30V × N.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when Vsum > 2.40V × N.
Source:
FLS-ES232LC-S.pdf0x10C1Low insulation fault (level 1).Warning— level 1
Cause
Insulation resistance ≤ 1000 Ω/V.
Recommended fix
Send faults to EMS. Recovers when > 1100 Ω/V.
Source:
FLS-ES232LC-S.pdf0x10C2Low insulation fault (level 2).Fault— level 2
Cause
Insulation resistance ≤ 500 Ω/V.
Recommended fix
Send faults to EMS and limit power. Recovers when > 600 Ω/V.
Source:
FLS-ES232LC-S.pdf0x10C3Low insulation fault, single cabinet with no MBCU (level 3).Critical— level 3
Cause
Insulation resistance ≤ 100 Ω/V.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x10D1Battery cluster excessive temperature difference alarm (level 1).Warning— level 1
Cause
Cell temperature spread > 8°C.
Recommended fix
Send faults externally. Recovers when < 6°C.
Source:
FLS-ES232LC-S.pdf0x10D2Battery cluster excessive temperature difference alarm (level 2).Fault— level 2
Cause
Cell temperature spread > 13°C.
Recommended fix
Send faults externally and limit power. Recovers when < 8°C.
Source:
FLS-ES232LC-S.pdf0x10D3Battery cluster excessive temperature difference alarm (level 3).Critical— level 3
Cause
Cell temperature spread > 15°C.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when < 13°C.
Source:
FLS-ES232LC-S.pdf0x10E1Battery cluster cell excessive voltage difference alarm (level 1).Warning— level 1
Cause
Cell voltage spread > 500 mV.
Recommended fix
Send faults externally. Recovers when < 300 mV.
Source:
FLS-ES232LC-S.pdf0x10E2Battery cluster cell excessive voltage difference alarm (level 2).Fault— level 2
Cause
Cell voltage spread > 3600 mV.
Recommended fix
Send faults externally and limit power. Recovers when < 500 mV.
Source:
FLS-ES232LC-S.pdf0x10E3Battery cluster cell excessive voltage difference alarm (level 3).Critical— level 3
Cause
Cell voltage spread > 4000 mV.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when < 3600 mV.
Source:
FLS-ES232LC-S.pdf0x10F1Low battery cluster SOC alarm.Warning— level 1
Cause
SOC < 3%.
Recommended fix
Send faults externally. Recovers when SOC > 5% (threshold subject to actual operating conditions).
Source:
FLS-ES232LC-S.pdf0x20B1Battery cluster SBCU internal bus voltage sampling fault (after applying high voltage).Warning— level 1
Cause
Invalid internal bus voltage sampling.
Recommended fix
Send faults externally, cluster disables insulation detection function. Recovers on normal sampling.
Source:
FLS-ES232LC-S.pdf0x20B3Battery cluster SBCU internal bus voltage sampling fault (before applying high voltage).Critical— level 3
Cause
Invalid internal bus voltage sampling.
Recommended fix
Send faults externally, cluster disables insulation detection function with high voltage prohibited. Recovers on normal sampling.
Source:
FLS-ES232LC-S.pdf0x20C3Battery cluster SBCU external bus voltage sampling fault.Critical— level 3
Cause
Invalid external bus voltage sampling.
Recommended fix
Send faults externally, limit power and request to lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x20D3Battery cluster SBCU insulation sampling circuit fault (before applying high voltage).Critical— level 3
Cause
Invalid insulation sampling partial voltage value.
Recommended fix
Send faults externally, cluster disables insulation detection function with high voltage prohibited. Recovers on normal sampling.
Source:
FLS-ES232LC-S.pdf0x20E3Battery cluster high-voltage box current sampling module fault.Critical— level 3
Cause
Current sampling value reading fails.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers on successful current sampling read.
Source:
FLS-ES232LC-S.pdf0x20F1SBCU-EE storage failure.Warning— level 1
Cause
Communication of EE fails while reading or writing.
Recommended fix
Send faults externally. Recovers when EE communication succeeds.
Source:
FLS-ES232LC-S.pdf0x30B3Battery cluster high-voltage box NTC failure.Warning— level 1
Cause
SBCU detects BJB_NTC sampling value as invalid.
Recommended fix
Send faults externally. Recovers when BJB_NTC sampling value valid.
Source:
FLS-ES232LC-S.pdf0x40F2Failure to disconnect the main positive circuit relay in the battery cluster high-voltage box.Critical— level 3
Cause
Sticking failure - main positive relay cannot open.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x90A3PACK high-voltage connector overtemperature.Critical— level 3
Cause
Temp21 or Temp22 on any BMU as judged by SBCU: T > 90°C.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Latch - manual troubleshooting is required.
Source:
FLS-ES232LC-S.pdf0x1011Battery cluster cell overtemperature alarm (level 1).Warning— level 1
Cause
Cell maximum temperature > 50°C.
Recommended fix
Send faults externally. Recovers when Temp_max < 45°C.
Source:
FLS-ES232LC-S.pdf0x1012Battery cluster cell overtemperature alarm (level 2).Fault— level 2
Cause
Cell maximum temperature > 55°C.
Recommended fix
Send faults externally and limit power. Recovers when Temp_max < 50°C.
Source:
FLS-ES232LC-S.pdf0x1013Battery cluster cell overtemperature alarm (level 3).Critical— level 3
Cause
Cell maximum temperature > 60°C.
Recommended fix
Send faults externally, limit power and request to lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when Temp_max < 55°C.
Source:
FLS-ES232LC-S.pdf0x1021Battery cluster cell undertemperature alarm (level 1).Warning— level 1
Cause
Cell minimum temperature < 5°C.
Recommended fix
Send faults externally. Recovers when Temp_min > 10°C.
Source:
FLS-ES232LC-S.pdf0x1022Battery cluster cell undertemperature alarm (level 2).Fault— level 2
Cause
Cell minimum temperature < 0°C.
Recommended fix
Send faults externally and limit power. Recovers when Temp_min > 5°C.
Source:
FLS-ES232LC-S.pdf0x1023Battery cluster cell undertemperature alarm (level 3).Critical— level 3
Cause
Cell minimum temperature < -30°C.
Recommended fix
Send faults externally, limit power and request to lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when Temp_min > 0°C.
Source:
FLS-ES232LC-S.pdf0x1031Battery cluster cell overvoltage alarm (level 1).Warning— level 1
Cause
Cell voltage > 3,650 mV.
Recommended fix
Send faults externally. Recovers when < 3,600 mV.
Source:
FLS-ES232LC-S.pdf0x1032Battery cluster cell overvoltage alarm (level 2).Fault— level 2
Cause
Cell voltage > 3,700 mV.
Recommended fix
Send faults externally and limit power. Recovers when < 3,650 mV.
Source:
FLS-ES232LC-S.pdf0x1033Battery cluster cell overvoltage alarm (level 3).Critical— level 3
Cause
Cell voltage > 3,800 mV.
Recommended fix
Send faults externally, limit power and request lower high voltage; immediately cut off the main circuit relay. Recovers when < 3,700 mV.
Source:
FLS-ES232LC-S.pdf0x1041Battery cluster cell undervoltage alarm (level 1).Warning— level 1
Cause
Cell voltage < 2,500 mV.
Recommended fix
Send faults externally. Recovers when > 2,600 mV.
Source:
FLS-ES232LC-S.pdf0x1042Battery cluster cell undervoltage alarm (level 2).Fault— level 2
Cause
Cell voltage < 2,400 mV.
Recommended fix
Send faults externally and limit power. Recovers when > 2,500 mV.
Source:
FLS-ES232LC-S.pdf0x1043Battery cluster cell undervoltage alarm (level 3).Critical— level 3
Cause
Cell voltage < 2,300 mV.
Recommended fix
Send faults externally, limit power and request lower high voltage; immediately cut off the main circuit relay. Recovers when > 2,400 mV.
Source:
FLS-ES232LC-S.pdf0x1051Battery cluster charging current exceeding limit alarm (level 1).Warning— level 1
Cause
Charging current > 105% × allowable current.
Recommended fix
Send faults externally. Recovers when < 100% allowable current.
Source:
FLS-ES232LC-S.pdf0x1052Battery cluster charging current exceeding limit alarm (level 2).Fault— level 2
Cause
Charging current > 110% × allowable current.
Recommended fix
Send faults externally and limit power. Recovers when < 105% allowable current.
Source:
FLS-ES232LC-S.pdf0x1053Battery cluster charging current exceeding limit alarm (level 3).Critical— level 3
Cause
Charging current > 130% × allowable current.
Recommended fix
Send faults externally, limit power and request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x1061Battery cluster discharging current exceeding limit alarm (level 1).Warning— level 1
Cause
Discharging current > 105% × allowable current.
Recommended fix
Send faults externally. Recovers when < 100% allowable current.
Source:
FLS-ES232LC-S.pdf0x1062Battery cluster discharging current exceeding limit alarm (level 2).Fault— level 2
Cause
Discharging current > 110% × allowable current.
Recommended fix
Send faults externally and limit power. Recovers when < 105% allowable current.
Source:
FLS-ES232LC-S.pdf0x1063Battery cluster discharging current exceeding limit alarm (level 3).Critical— level 3
Cause
Discharging current > 130% × allowable current.
Recommended fix
Send faults externally, limit power and request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x1103Battery cluster voltage mismatch fault.Critical— level 3
Cause
|Slave plate voltage sum - internal bus voltage| > 40V.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x1183Low battery cluster SOH alarm.Critical— level 3
Cause
SOH < 60%.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Latch - Administrator permissions are required to troubleshoot.
Source:
FLS-ES232LC-S.pdf0x2013Loss of communication between battery cluster SBCU and BMU.Critical— level 3
Cause
No signal received or life signal unchanged.
Recommended fix
Send faults externally, limit power and request to lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when life signal changed.
Source:
FLS-ES232LC-S.pdf0x2083Loss of communication between battery cluster SBCU and BMCU.Critical— level 3
Cause
No signal received or life signal unchanged.
Recommended fix
Send faults externally, limit power and request to lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when life signal changed.
Source:
FLS-ES232LC-S.pdf0x2133Fire system communication loss.Critical— level 3
Cause
No signal received or life signal unchanged from fire system.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x2153Communication loss between SBCU and EMS (for liquid-cooled single cabinet).Critical— level 3
Cause
No signal received or life signal unchanged.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x2163PCS communication loss.Critical— level 3
Cause
No signal received or life signal unchanged from PCS.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x317333772 communication loss.Critical— level 3
Cause
Unsuccessful reboot of 33772 chip 10 times within 1s.
Recommended fix
Send faults to EMS, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers on communication recovered.
Source:
FLS-ES232LC-S.pdf0x4013Failure to connect the main positive circuit relay in the battery cluster high-voltage box.Critical— level 3
Cause
Open-circuit fault detected on main positive relay.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x4143Battery cluster relay sticking detection circuit failure.Critical— level 3
Cause
After low voltage applied without enabling relay: DO4 input voltage not 20-32V or DI1/2 feedback state is 0; after enabling relay: DO4 input voltage not 20-32V or DI1/2 feedback state is 1.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x5182Battery cluster SBCU wakeup loss.Critical— level 3
Cause
Anomalous high-voltage state (wakeup loss & EMS communication loss); cut-off with 5s delay and dormant. Trigger: < 9V.
Recommended fix
Send faults externally. (1) Non-high-voltage state dormant; (2) Normal high-voltage state hold; (3) Anomalous high-voltage state cut-off. Recovers when ≥ 9V.
Source:
FLS-ES232LC-S.pdf0x5192Battery cluster system voltage mismatch fault.Critical— level 3
Cause
Actual voltage quantity does not match software configuration.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Detection starts 10s after Device powered on.
Source:
FLS-ES232LC-S.pdf0x8023Battery cluster thermal runaway alarm.Critical— level 3
Cause
Thermal runaway detected by any of: 1) Vmin<0.5V & Tmax>65°C; 2) Vmin<0.5V & Tmax-Tmin>30°C; 3) Vmin<0.5V & dT/dt>1°C/s; 4) Voltage sampling disconnection fault & Tmax>65°C; 5) Voltage sampling disconnection fault & Tmax-Tmin>30°C; 6) Voltage sampling disconnection fault & dT/dt>1°C/s; Vmin<0.5V & NTC sampling break or short circuit; Aerosol operation (AI1>9V on any BMU as judged by SBCU) & Tmax>65°C; Any BMU air pressure change rate ≥ 0.1 kPa/s.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Latch - manual troubleshooting is required.
Source:
FLS-ES232LC-S.pdf0x8051Aerosol operation alarm in battery pack.Critical— level 3
Cause
Aerosol operation (AI1 > 9V on any BMU as judged by SBCU).
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x9012Manual disconnect switch (QS) in the battery cluster high-voltage box is disconnected.Critical— level 3
Cause
QS feedback signal anomaly detected inside SBCU (judgment made only after receiving applying high voltage command).
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x9022Fuse (FU1) in the battery cluster high-voltage box is disconnected.Critical— level 3
Cause
FU1 feedback signal anomaly detected inside SBCU.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay.
Source:
FLS-ES232LC-S.pdf0x9052Excessive temperature in the high-voltage box of the battery cluster.Critical— level 3
Cause
SBCU detects BJB_NTC > 60°C.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers when BJB_NTC < 50°C.
Source:
FLS-ES232LC-S.pdf0x9062Battery cluster SBCU relay drive supply voltage differences.Critical— level 3
Cause
Relay drive supply voltage < 22V.
Recommended fix
Send faults externally, limit power, request lower high voltage; if command not received within 5s, cut off the main circuit relay. Recovers at ≥ 22V.
Source:
FLS-ES232LC-S.pdfHVAC-COMP-NOSTARTCompressor does not start.Fault
Cause
Power off, loose circuit connection, or compressor damaged.
Recommended fix
Check main power switch and operation display screen; tighten circuit connector; check compressor and replace if damaged.
Source:
FLS-ES232LC-S.pdfHVAC-COMP-NOWORKCompressor does not work.Fault
Cause
Water temperature set too high (no cooling required) or shutdown delay (compressor minimum shutdown time).
Recommended fix
Check inlet/outlet temperature display and reset control temperature. The compressor will restart with delay if temperature rises again.
Source:
FLS-ES232LC-S.pdfHVAC-COOL-POORPoor cooling effect.Fault
Cause
Insufficient refrigerant; insufficient water flow; serious dust accumulation in condenser; refrigeration system clogged.
Recommended fix
Replenish refrigerant; clean water filter and check water pump; clean condenser; check or replace filter drier.
Source:
FLS-ES232LC-S.pdfHVAC-FAN-NOISEAbnormal noise of fan.Fault
Cause
Worn fan bearings or fan blades scrape against other objects.
Recommended fix
Replace the fan. Check whether any cables interfere with the fan blades.
Source:
FLS-ES232LC-S.pdfHVAC-FAN-NORUNFan does not run.Fault
Cause
Fan failure or fan stuck.
Recommended fix
Check the motor and replace it immediately if defects are found. Check whether any foreign matters are stuck in the fan.
Source:
FLS-ES232LC-S.pdfHVAC-HEAT-NOWORKElectric heating tube does not work.Fault
Cause
Water temperature set too low (no heating required), loose circuit connection, or electric heating tube burnout.
Recommended fix
Check outlet temperature and heating set point; tighten circuit connector; replace burnt-out heating tube.
Source:
FLS-ES232LC-S.pdfHVAC-HV-PROTHigh voltage protection fault.Fault
Cause
Condenser dirty plugging or external circulation fan does not operate.
Recommended fix
Clean the condenser. Check the fan.
Source:
FLS-ES232LC-S.pdfHVAC-LV-PROTLow voltage protection fault.Fault
Cause
Leakage of fluorine or insufficient refrigerant; filter drier clogging; thermal expansion valve failure; water flow rate too low.
Recommended fix
Leak check and replenish refrigerant; replace filter drier; check expansion valve and temperature sensing package; fix water system.
Source:
FLS-ES232LC-S.pdfHVAC-PUMP-FAILCirculating water pump does not start or operates improperly.Fault
Cause
Power off, loose circuit connection, damaged water pump, or air in cooling medium / no cooling medium.
Recommended fix
Check main power switch; tighten circuit connector; replace damaged water pump; evacuate air or replenish cooling medium.
Source:
FLS-ES232LC-S.pdfPCS-ARM-01ARM software fault - phase A output overcurrent.Fault— level 2
Cause
Phase A output overcurrent.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified. More than 3 faults in one day require manual intervention to confirm grid quality on site.
Source:
FLS-ES232LC-S.pdfPCS-ARM-02ARM software fault - phase A output quick disconnection.Fault— level 2
Cause
Phase A output quick disconnection.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified.
Source:
FLS-ES232LC-S.pdfPCS-ARM-03ARM software fault - phase B output overcurrent.Fault— level 2
Cause
Phase B output overcurrent.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified.
Source:
FLS-ES232LC-S.pdfPCS-ARM-04ARM software fault - phase B output quick disconnection.Fault— level 2
Cause
Phase B output quick disconnection.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified.
Source:
FLS-ES232LC-S.pdfPCS-ARM-05ARM software fault - phase C output overcurrent.Fault— level 2
Cause
Phase C output overcurrent.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified.
Source:
FLS-ES232LC-S.pdfPCS-ARM-06ARM software fault - phase C output quick disconnection.Fault— level 2
Cause
Phase C output quick disconnection.
Recommended fix
Reset to restart. Manual intervention required if fault cannot be rectified.
Source:
FLS-ES232LC-S.pdfPCS-ARM-07ARM software fault - phase N output quick disconnection.Fault— level 2
Cause
Phase N output quick disconnection.
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-08ARM software fault - phase N output quick disconnection (2).Fault— level 2
Cause
Phase N output quick disconnection (duplicate entry).
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-09ARM software fault - AC overvoltage.Warning— level 1
Cause
AC bus overvoltage.
Recommended fix
Reset to restart. When AC undervoltage cannot be recovered: 1) Check whether AC switch is disconnected or grid is blacked out; 2) Where there is no disconnection, confirm whether the AC insurance is blown.
Source:
FLS-ES232LC-S.pdfPCS-ARM-10ARM software fault - AC undervoltage.Warning— level 1
Cause
AC bus undervoltage.
Recommended fix
Reset to restart. Check AC switch and AC fuse.
Source:
FLS-ES232LC-S.pdfPCS-ARM-11ARM software fault - output overvoltage.Warning— level 1
Cause
Output side overvoltage (off-grid).
Recommended fix
Cannot reset to restart. Off-grid output AC overvoltage. Check whether the Device can work with no load.
Source:
FLS-ES232LC-S.pdfPCS-ARM-12ARM software fault - output undervoltage.Warning— level 1
Cause
Output side undervoltage (off-grid).
Recommended fix
Reset to restart. Off-grid output AC undervoltage. Check whether the device is in an overload state.
Source:
FLS-ES232LC-S.pdfPCS-ARM-13ARM software fault - voltage THDU exceeds the limit.Warning— level 1
Cause
Voltage total harmonic distortion exceeds limit.
Recommended fix
Reset to restart. Check whether THDU of the power grid exceeds 15%; confirm instantaneous power of load is within design range of system distribution.
Source:
FLS-ES232LC-S.pdfPCS-ARM-14ARM software fault - system phase loss.Warning— level 1
Cause
Loss of one or more grid phases.
Recommended fix
PCS shall be automatically reset and restarted after the fault is rectified on the site. Check whether the wiring misses a phase.
Source:
FLS-ES232LC-S.pdfPCS-ARM-15ARM software fault - system phase sequence error.Warning— level 1
Cause
Phase sequence reversed/incorrect.
Recommended fix
PCS shall be automatically reset and restarted after the fault is rectified on the site. Check correspondence between ABCN phase sequence and the modules.
Source:
FLS-ES232LC-S.pdfPCS-ARM-16ARM software fault - DC polarity reverse connection.Warning— level 1
Cause
DC terminals connected with reversed polarity.
Recommended fix
PCS shall be automatically reset and restarted after the fault is rectified on the site. Check the voltage polarity of the PCS DC terminal.
Source:
FLS-ES232LC-S.pdfPCS-ARM-17ARM software fault - DC bus software overvoltage.Warning— level 1
Cause
DC bus overvoltage detected by software.
Recommended fix
Reset to restart. Measure battery voltage of PCS DC terminal within allowable range; check contactor of high-voltage box, DC fuse, DC soft start. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-18ARM software fault - DC busbar software undervoltage.Warning— level 1
Cause
DC busbar undervoltage detected by software.
Recommended fix
Reset to restart. Measure battery voltage; check contactor and DC fuse. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-19ARM software fault - system overfrequency.Fault— level 2
Cause
Grid frequency too high.
Recommended fix
Reset to restart. Check whether grid frequency is beyond range of frequency protection action. Check for AC disconnection or islanding.
Source:
FLS-ES232LC-S.pdfPCS-ARM-20ARM software fault - system underfrequency.Fault— level 2
Cause
Grid frequency too low.
Recommended fix
Reset to restart. Check whether grid frequency is beyond range of frequency protection action. Check for AC disconnection or islanding.
Source:
FLS-ES232LC-S.pdfPCS-ARM-21ARM software fault - DC charging overcurrent.Fault— level 2
Cause
DC charging current exceeded threshold.
Recommended fix
Reset to restart. Check system power settings do not exceed rated capacity; check actual battery voltage range. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-22ARM software fault - DC discharging overcurrent.Fault— level 2
Cause
DC discharging current exceeded threshold.
Recommended fix
Reset to restart. Check system power settings do not exceed rated capacity; check actual battery voltage range. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-23ARM software fault - islanding protection.Fault— level 2
Cause
Islanding condition detected.
Recommended fix
Reset to restart. Where an islanding is detected, the device is shut down from the on-grid state.
Source:
FLS-ES232LC-S.pdfPCS-ARM-24ARM software fault - DC component exceedance.Warning— level 1
Cause
DC component exceeds limit.
Recommended fix
Reset to restart. 1) Report fault to manufacturer. 2) Contact manufacturer if it occurs 2 times in one day.
Source:
FLS-ES232LC-S.pdfPCS-ARM-25ARM software fault - AC main connection switching-on failure.Fault— level 2
Cause
AC main contactor failed to close.
Recommended fix
Reset to restart. Does not occur on domestic version. if foreign version reports during startup three consecutive times, contact manufacturer to confirm insulation detection logic and contactor sticking.
Source:
FLS-ES232LC-S.pdfPCS-ARM-26ARM software fault - AC main connection switching-off failure.Fault— level 2
Cause
AC main contactor failed to open.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-27ARM software fault - AC soft start switching-on failure.Fault— level 2
Cause
AC soft start failed to close.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-28ARM software fault - AC soft start switching-off failure.Fault— level 2
Cause
AC soft start failed to open.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-29ARM software fault - DC main connection switching-on failure.Fault— level 2
Cause
DC main contactor failed to close.
Recommended fix
Reset to restart. Does not occur on device adopting 'One Cluster, One Management' approach.
Source:
FLS-ES232LC-S.pdfPCS-ARM-30ARM software fault - DC main connection switching-off failure.Fault— level 2
Cause
DC main contactor failed to open.
Recommended fix
Reset to restart. Does not occur on device adopting 'One Cluster, One Management' approach.
Source:
FLS-ES232LC-S.pdfPCS-ARM-31ARM software fault - DC soft start switching-on failure.Warning— level 1
Cause
DC soft start failed to close.
Recommended fix
Cannot reset to restart, manual confirmation required. 1) Check DC voltage sampling and calibration deviation. 2) Check whether DC soft start resistance is damaged.
Source:
FLS-ES232LC-S.pdfPCS-ARM-32ARM software fault - DC soft start switching-off failure.Fault
Cause
DC soft start failed to open.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-33ARM software fault - ferroelectric parameter storage error.Warning— level 1
Cause
Ferroelectric memory parameter storage error.
Recommended fix
Cannot reset to restart. Where PCS internal memory is faulty, contact the manufacturer.
Source:
FLS-ES232LC-S.pdfPCS-ARM-34ARM software fault - DC soft start failure.Warning— level 1
Cause
DC soft start failure (general).
Recommended fix
Reset to restart. Report to manufacturer if it occurs three consecutive times during startup. 1) DC contactor switching-on under judgment, DC voltage difference too large. 2) When running with DCDC, DCDC startup not correct.
Source:
FLS-ES232LC-S.pdfPCS-ARM-35ARM software fault - reserved.Fault
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-36ARM software fault - reserved.Fault
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-37ARM software fault - start-up conditions are not met.Fault— level 2
Cause
Start-up preconditions failed.
Recommended fix
Reset to restart. Check whether off-grid and on-grid setting matches actual wiring; after disconnecting from grid with no load, wait for AC terminal voltage to drop to near 0 before starting again.
Source:
FLS-ES232LC-S.pdfPCS-ARM-38ARM software fault - switch fault in operation.Fault— level 2
Cause
Switch fault during operation.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-39ARM software fault - inverter startup timeout.Fault— level 2
Cause
Inverter did not start within timeout.
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-40ARM software fault - parameter delivery setting error.Fault— level 2
Cause
Parameter setting error.
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-41ARM software fault - BMS communication failure.Fault— level 2
Cause
Communication with BMS lost.
Recommended fix
Reset to restart. Automatic reset after communication is restored.
Source:
FLS-ES232LC-S.pdfPCS-ARM-42ARM software fault - abnormal BMS temperature.Fault— level 2
Cause
BMS reported abnormal temperature.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-ARM-43ARM software fault - BMS abort.Warning— level 1
Cause
BMS abort signal received.
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-44ARM software fault - BMS battery alarm.Critical— level 3
Cause
BMS battery alarm received.
Recommended fix
Alarm only, the device does not stop.
Source:
FLS-ES232LC-S.pdfPCS-ARM-45ARM software fault - DCDC communication failure.Fault— level 2
Cause
Communication with DCDC lost.
Recommended fix
PCS and DCDC communication timeout.
Source:
FLS-ES232LC-S.pdfPCS-ARM-46ARM software fault - EMS communication failure.Warning— level 1
Cause
Communication with EMS lost.
Recommended fix
Reset to restart.
Source:
FLS-ES232LC-S.pdfPCS-ARM-47ARM software fault - emergency stop or core failure.Warning— level 1
Cause
External emergency stop signal or internal core failure.
Recommended fix
Reset to restart, external dry node signal shall disappear.
Source:
FLS-ES232LC-S.pdfPCS-ARM-48ARM software fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-ARM-49ARM software fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-ARM-50ARM software fault - battery software overvoltage.Warning— level 1
Cause
Battery overvoltage detected by software.
Recommended fix
Reset to restart. Measure battery voltage; check contactor of high-voltage box, DC fuse. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-51ARM software fault - battery software undervoltage.Warning— level 1
Cause
Battery undervoltage detected by software.
Recommended fix
Reset to restart. Measure battery voltage; check contactor of high-voltage box, DC fuse. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-52ARM software fault - abnormal busbar imbalance.Warning— level 1
Cause
Bus imbalance detected.
Recommended fix
Reset to restart. 1) Fault elimination lasts about 1h after DC cut off. 2) if cannot be reset, contact manufacturer for voltage sampling and capacitor aging issues. 3) if reset works but repeatedly reports after startup, contact manufacturer.
Source:
FLS-ES232LC-S.pdfPCS-ARM-53ARM software fault - busbar semi-direct voltage overvoltage.Warning— level 1
Cause
Half-bus voltage overvoltage.
Recommended fix
Reset to restart. Measure battery voltage; check contactor and DC fuse. More than 3 faults in one day require manual intervention.
Source:
FLS-ES232LC-S.pdfPCS-ARM-54ARM software fault - DCDC startup timeout.Fault— level 2
Cause
DCDC did not start within timeout.
Recommended fix
Reset to restart. Check communication cables between PCS and DCDC and the baud rate.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-01FPGA hardware fault - phase A hardware overcurrent.Fault— level 2
Cause
Phase A hardware overcurrent detected by FPGA.
Recommended fix
Reset to restart. More than 3 faults in one day require manual intervention to confirm the grid quality on site.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-02FPGA hardware fault - phase B hardware overcurrent.Fault— level 2
Cause
Phase B hardware overcurrent detected by FPGA.
Recommended fix
Reset to restart. More than 3 faults in one day require manual intervention to confirm the grid quality on site.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-03FPGA hardware fault - phase C hardware overcurrent.Fault— level 2
Cause
Phase C hardware overcurrent detected by FPGA.
Recommended fix
Reset to restart. More than 3 faults in one day require manual intervention to confirm the grid quality on site.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-04FPGA hardware fault - phase N hardware overcurrent.Fault— level 2
Cause
Phase N hardware overcurrent detected by FPGA.
Recommended fix
Reset to restart. More than 3 faults in one day require manual intervention to confirm the grid quality on site.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-05FPGA hardware fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-FPGA-06FPGA hardware fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-FPGA-07FPGA hardware fault - unit direct voltage fault.Warning— level 1
Cause
Unit DC voltage abnormal.
Recommended fix
Reset to restart. Check whether the contactor of the high-voltage box has been disconnected. if the device fails to start after reset, manual intervention is required to check whether the DC fuse is blown.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-08FPGA hardware fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-FPGA-09FPGA hardware fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfPCS-FPGA-10FPGA hardware fault - switching power supply undervoltage.Warning— level 1
Cause
Switching power supply undervoltage.
Recommended fix
Reset to restart. Check whether the contactor of the high-voltage box has been disconnected.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-11FPGA software fault - phase A IGBT failure.Fault
Cause
Phase A IGBT failure.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-12FPGA hardware fault - phase B IGBT failure.Fault
Cause
Phase B IGBT failure.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-13FPGA hardware fault - phase C IGBT failure.Fault
Cause
Phase C IGBT failure.
Recommended fix
No alarm is generated for the current device.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-14FPGA hardware fault - phase N IGBT failure.Fault
Cause
Phase N IGBT failure.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-15FPGA hardware fault - overtemperature failure.Warning— level 1
Cause
Internal overtemperature.
Recommended fix
Reset to restart. if over-temperature persists, consider derating depending on ambient temperature: derate 6kW per degree for ambient temperature over 45 degrees. Check fan operation, over-temperature protection threshold, and whether the container is exposed to sunlight without shade.
Source:
FLS-ES232LC-S.pdfPCS-FPGA-16FPGA hardware fault - reserved.Fault
Source:
FLS-ES232LC-S.pdfStep-by-step troubleshooting checklist
- 1.Note the exact code and timing
Write down the exact code shown on the display, what the unit was doing when it appeared (charging, discharging, idle, grid-tied), and any LEDs or audible alarms. The same code can have different fixes depending on context.
- 2.Check the recommended fix on this page
Find the code in the list below and read the cause + recommended fix. Most warning-level codes can be cleared by following the listed action — usually reducing load, checking wiring, or restarting the unit.
- 3.Verify the source manual page
Each code shows the source manual filename and page number. Open that exact page in the official manual to verify model-specific notes (firmware version, parallel-config notes, regional variants) before acting.
- 4.Disconnect AC, DC, and battery before opening
If a fix requires opening the enclosure or accessing terminals, disconnect AC input, DC PV, and battery in that order. Wait at least 60 seconds for capacitors to discharge before touching any conductors.
- 5.Escalate critical codes to authorized service
Critical codes (short-circuit, IGBT failure, BMS hardware error) should not be cleared by end users. Note the code, model number, and source manual page, then contact an authorized service partner.
Common questions about FLS-ES232LC-S error codes
- Where can I find the official Felicity FLS-ES232LC-S error code manual?
- Each code on this page lists the official source manual filename and page number at the bottom. The manuals are published by Felicity on their website; we compile the codes here so you can search across all of them at once instead of opening each PDF.
- Is the FLS-ES232LC-S the same as other Felicity models?
- Some Felicity units share firmware across a family of variants — the same fault codes apply to multiple model numbers. Look at the "also covers" chips below the title to see which other model numbers this page applies to.
- What's the most critical code on a Felicity FLS-ES232LC-S?
- Critical-severity codes (red dot) are the ones that trip the unit offline immediately — typically short-circuit, IGBT, or BMS hardware failures. These are listed first when you filter by severity. Do not bypass them; they indicate a hardware or safety condition that requires service.
Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.