This is the complete fault table for the Felicity LUX-X-48050LG01 Battery family — 27 codes shared by 6 model numbers, transcribed from the official manual. On this Felicity device, a fault code means the unit has entered protection and stopped normal operation; a warning leaves it running. The exact indication (LED pattern or display code) is listed per code below.
Last checked against the official manuals on July 10, 2026.
Battery pack voltage above safe operating threshold (BMS protection flag).
CauseBattery voltage has exceeded the configured high-voltage cutoff. Usually a misconfigured charge profile, a runaway charger, or a fault in the battery management system.
Recommended fixBMS protection flag displayed on LCD information page. Restart unit; if persists, return to repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Battery pack voltage below safe operating threshold (BMS protection flag).
CauseBattery voltage has fallen below the configured low-voltage cutoff. Causes: deep discharge during a long outage, undersized battery for the load, failing cells, or incorrect battery type setting.
Recommended fixBMS protection flag. Charge battery via mains or solar power as soon as possible to avoid over-discharge lockout.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
BMS internal temperature above safe operating range.
CauseBMS overheating from high ambient temperature, poor ventilation, or sustained high-current operation.
Recommended fixBMS protection flag. Check ambient temperature, ensure ventilation, operate within 0-55 C charge / -20 to 55 C discharge.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
BMS internal temperature below safe operating range.
CauseBMS temperature is below the operating range — the ambient environment is too cold.
Recommended fixBMS protection flag. Check ambient temperature is not too low.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Battery overvoltage.
CauseTotal battery pack voltage exceeded the upper protection threshold — charging continued past the over-voltage protection point.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Battery undervoltage.
CauseTotal battery pack voltage fell below the lower protection threshold — an over-discharge condition.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Cell overvoltage.
CauseA single cell voltage reached the protection value during charging — typically cell imbalance letting one cell drift above its safe ceiling.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Cell undervoltage.
CauseA single cell voltage fell below the protection value during discharge — deep discharge or a weak, aged cell pulling below the limit.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Charge overcurrent.
CauseCharging current exceeded the protection trigger value — the inverter or charger charge-current setting is too high for this pack.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Discharge overcurrent.
CauseDischarging current exceeded the protection trigger value — the connected load or inverter discharge current is too high.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
MOS overtemperature.
CauseInverter internal temperature has exceeded the safe operating threshold. Causes include high ambient temperature, blocked cooling vents, failed cooling fan, or installation in direct sunlight.
Recommended fix1. The inner temperature is over the limitation. 2. Check whether the ambient temperature is too high.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
MOS undertemperature.
CauseInverter ambient temperature is below the minimum operating range. Most common in unheated outdoor installs in winter.
Recommended fix1. The internal temperature is lower than the limit range. 2. Check whether the ambient temperature is too low.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Cell overtemperature.
CauseInverter internal temperature has exceeded the safe operating threshold. Causes include high ambient temperature, blocked cooling vents, failed cooling fan, or installation in direct sunlight.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Cell undertemperature.
CauseInverter ambient temperature is below the minimum operating range. Most common in unheated outdoor installs in winter.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Abnormal current sampling.
CauseThe internal current sensor or sampling circuit reported abnormal values — an internal BMS hardware fault.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Abnormal output impedance.
CauseOutput impedance is outside the normal range — possibly a loose connection, oxidised terminal, or unusual load.
Recommended fixRestart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Battery cell temperature above safe operating range.
CauseCell overheating from high ambient temperature or high-current operation.
Recommended fixBMS protection flag. Check ambient temperature, ensure ventilation.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Battery cell temperature below safe operating range.
CauseCell temperature is below the charge/discharge range — the ambient environment is too cold.
Recommended fixBMS protection flag. Check ambient temperature; do not charge below 0 C.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Individual cell voltage above safe limit (BMS protection flag).
CauseAn individual cell is over its voltage limit — cell imbalance or overcharge of a single cell.
Recommended fixBMS protection flag. Restart unit; if persists, return to repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Individual cell voltage below safe limit (BMS protection flag).
CauseAn individual cell is under its voltage limit — cell imbalance or deep discharge of a single cell.
Recommended fixBMS protection flag. Charge battery as soon as possible.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Charging current exceeds maximum allowable value (BMS protection flag).
CauseCharging current exceeds the allowed maximum — the inverter or charger is pushing too much current into the pack.
Recommended fixBMS protection flag. Verify charge current within rated limits (Recommend 25A/40A; Max continuous 50A/80A; Peak 100A/200A/300A).
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Current sensor reading is abnormal / sampling failure.
CauseThe BMS current sensor or sampling circuit is returning abnormal readings — an internal hardware fault.
Recommended fixBMS protection flag. Restart unit; if persists, return to repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Discharging current exceeds maximum allowable value (BMS protection flag).
CauseDischarging current exceeds the allowed maximum — the connected load is drawing too much current from the battery.
Recommended fixBMS protection flag. Verify load current within rated limits.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 16
Battery in low-power state, output disabled (SOC LEDs OFF).
CauseThe battery has discharged to a very low state of charge, and the BMS has disabled output to prevent over-discharge damage.
Recommended fixCharge the battery as soon as possible when main power or solar energy is available. Note: Over-discharged pack may not be reactivated by AC/PV cable and may require special charging activation.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 15
Output power loss / no output.
CauseNo output from the battery pack — the circuit breaker may be open or the fuse may be blown.
Recommended fix1. Please check whether the circuit breaker is closed; 2. Please check whether the fuse is normal; 3. Restart the unit, if the error persists, contact the repair center.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Parallel connection failure between battery units.
CauseA single unit is installed to a parallel system, or the wiring between paralleled units is incorrect or incomplete.
Recommended fix1. Please check if single unit is installed to parallel system. 2. if this error happens during parallel installation, please check wires connection. if they are connected correctly, please finish parallel installation first, and then restart the unit. 3. if the problem remains, please contact your installer.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 17
Low state of charge warning - LED1 flashing (default).
CauseState of charge has fallen below 10% — a low-battery warning rather than a fault; the pack needs charging soon.
Recommended fixCharge the battery as soon as possible. The battery should be fully charged at least once per month for accurate SOC calculation.
Source:LUX-X-48050LG01-low-voltage-battery-user-guide.pdf· page 15
Send us the code on your screen and a Felicity 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 Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.