Bus soft start fail
Also displayed as F33 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
Bus soft start fail
Cause: The DC bus failed to precharge during the soft-start sequence: failed internal components.
Source: ICM.pdf, p.14
Also applies to:IVGM6KL-P1G1IVGM7K6L-P1G1IVGM8KL-P1G1
Grid Over Voltage Alarm — Grid voltage is too high, check if the grid voltage is within the normal range.
Cause: The grid voltage measured at the AC terminals is above the inverter's permitted operating window, so it alarms and holds off grid-tied operation until the voltage returns to range.
Check if the grid voltage is within the normal range.
Source: Felicitysolar IVGM Series Hybrid inverter Instruction Manual.pdf, p.51
Also applies to:T-REX-3K6LP1G01T-REX-4KLP1G01T-REX-4K6LP1G01T-REX-5KLP1G01T-REX-6KLP1G01
Bus soft start failed — Internal components failed. Bus soft start failed.
Cause: Internal components failed — the DC bus could not be brought up to its working voltage during the soft-start ramp.
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.38
Also applies to:IVEM6048
Over current happen at LLC circuit
Cause: Overcurrent in LLC resonant circuit.
Restart the unit, if the error persists, contact the repair center.
Source: felicitysolar IVEM 6048 Solar Inverter User Guide.pdf, p.38
Also applies to:IVEM12048-IIIVEM 8K-12K Series II
Over current happen at LLC circuit
Cause: Over current detected in the LLC circuit.
Restart the unit, if the error persists, contact the repair center.
Source: IVEM8K-12K-II_compressed.pdf, p.44
Also applies to:IVEM8048
Over current happen at LLC circuit
Cause: The LLC resonant converter (the isolated DC link inside the unit) drew current above its protection limit.
Restart the unit, if the error persists, contact the repair center.
Source: FelicitySolar IVEM8048-LV Single Phase Hybrid Inverter User Guide.pdf, p.39
Bus soft start failed — DC bus soft start procedure failed.
Cause: Internal components failed.
Restart the unit, if the error persists, contact the repair center.
Source: T-REX-10KHP3G01-Inverter-User-Guide.pdf, p.29
Also applies to:Apollo-5KLP1G01-MXApollo-5KLP1G01-M1Apollo-5KLP1G01-M2Apollo-4K6LP1G01-MXApollo-4K6LP1G01-M1Apollo-4K6LP1G01-M2
Bus soft start failed
Cause: Internal components failed.
Restart the unit, if the error persists, contact the repair center.
Source: T-REX-10KLP3G01-Inverter-User-Guide.pdf, p.28 · Apollo-5KLP1G01-All-in-one-ESS-User-Guide.pdf, p.43
Battery 2 SOC Low fault — Battery 2 SOC is too low, the battery should be charged.
Cause: Battery 2's state of charge has dropped below the protection threshold — the pack has too little usable energy left and must be charged.
Source: T-REX-50KHP3G01-user-manual-.pdf, p.46
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.