Low battery
Also displayed as F11 on some models.
Fault — the inverter cuts its output and the red LED stays solid until the fault is cleared.
The exact meaning depends on your model:
Also applies to:IVCM2024 PROIVCM3024 PRO
Low battery
Cause: The battery voltage has dropped below the low-battery threshold: the battery is discharged and needs charging.
The battery voltage is too low, it should be charging.
Source: ICM.pdf, p.13
Also applies to:T-REX-3K6LP1G01T-REX-4KLP1G01T-REX-4K6LP1G01T-REX-5KLP1G01T-REX-6KLP1G01T-REX-10KHP3G01T-REX-10KLP3G01
Over current happen at Buckboost
Cause: The buck-boost converter stage drew current above its protection limit.
Restart the unit, if the error persists, contact the repair center.
Source: T-REX-3_3.6_4_4.6_5_6KLP1G01-hybrid-inverter-user-guide-English.pdf, p.37 · T-REX-10KHP3G01-Inverter-User-Guide.pdf, p.28 · T-REX-10KLP3G01-Inverter-User-Guide.pdf, p.27
Also applies to:IVEM6048
Battery voltage is too high
Cause: Battery spec/quantity does not meet inverter requirements.
Check if spec and quantity of batteries are meet requirements.
Source: felicitysolar IVEM 6048 Solar Inverter User Guide.pdf, p.37
Also applies to:IVEM12048-IIIVEM 8K-12K Series II
Battery voltage is too high
Cause: Battery voltage exceeds the inverter's allowed maximum.
Check if spec and quantity of batteries are meet requirements.
Source: IVEM8K-12K-II_compressed.pdf, p.43
Also applies to:IVEM8048
Battery voltage is too high
Cause: Battery spec or quantity does not meet requirements.
Check if spec and quantity of batteries are meet requirements.
Source: FelicitySolar IVEM8048-LV Single Phase Hybrid Inverter User Guide.pdf, p.38
PV3 reverse connection fault — Pv3 string positive and negative connection, check the string wiring.
Cause: The PV3 string is connected with positive and negative reversed, so the input stage blocks it until the string wiring is corrected.
Source: T-REX-50KHP3G01-user-manual-.pdf, p.46
Also applies to:Apollo-5KLP1G01-M1Apollo-5KLP1G01-M2Apollo-4K6LP1G01-MXApollo-4K6LP1G01-M1Apollo-4K6LP1G01-M2
Over current happen at Buckboost — Over current detected at the Buckboost stage.
Cause: Over current at Buckboost.
Restart the unit, if the error persists, contact the repair center.
Source: Apollo-5KLP1G01-All-in-one-ESS-User-Guide.pdf, p.42
PV1 overcurrent — Fault event: PV input channel 1 current exceeded its limit (max input current 30A per MPPT).
Cause: A fault has been detected in the PV input stage — usually a short, ground fault, or isolation failure between the PV array and the inverter chassis. Wet connectors, damaged cable insulation, or moisture in a junction box are common causes.
Source: LUX-S-1600LG01.pdf, p.22
Also applies to:LUX-X-96050HMG01LUX-X-96050HCG01
AFE Fault — Analog Front End (AFE) fault detected by the BMS.
Cause: Internal BMS measurement IC (AFE) malfunction.
Restart, if the fault still exists, contact our engineer.
Source: LUX-X-96050HG01-Lithium-Battery-User-Guide.pdf, p.21
Also applies to:LUX-Y-48100HCG01LUX-Y-48100HMG01LUX-Y-48100HR13G01LUX-Y-48100HR9G01
AFE Fault — Analog Front End (AFE) measurement fault detected by the BMS.
Cause: Internal BMS measurement IC (AFE) malfunction.
Restart, if the fault still exists, contact our engineer.
Source: LUX-Y-48100HG01-Lithium-Battery-User-Guide.pdf, p.20
AFE Fault — AFE (Analog Front End) fault.
Cause: Internal BMS measurement IC (AFE) malfunction.
Source: LUX-Y-48100HG01MN User manual 358-S010025-03 0325(V2.0).pdf, p.27
Also applies to:SCCM4524-IIISCCM4548-IIISCCM6048-IIISCCM8048-IIISCCM10048-IIISCCM12048-III
MOS tube damaged — The MOSFET (power switching transistor) inside the controller is damaged.
Cause: Internal MOSFET hardware failure, often caused by overcurrent, short circuit, or surge events.
Source: felicitysolar SCCM-III MPPT Solar Charge Controller User Guide.pdf, p.18
All T-REX-3KLP1G01 codes All T-REX-10KHP3G01 codes All T-REX-10KLP3G01 codes
Prefer the full written guide? Read the complete Felicity inverter error-code guide
Compiled from official Felicity user manuals. Always consult your device manual and a qualified technician before performing repairs.