IVGM5-8K LP2G1 hybrid inverters (warning code list, flashing fault LED)
Felicity 36 error code
Grid under-frequency alarm: grid frequency is below the inverter's permitted operating window.
Likely causes
- Weak grid with frequency sagging under load
- Generator supplying the grid input with poor speed regulation
- Incorrect frequency setting (50 Hz vs 60 Hz)
- Measurement fault in the inverter
Checks to run, in order
- 1Measure grid frequency at the AC input
- 2Confirm the site is 50 Hz and the inverter is set to 50 Hz
- 3If a generator is used, check its governor and load
- 4Compare the inverter reading with a separate meter
Fixes
- Wait for grid frequency to recover
- Correct the inverter frequency setting
- Service the generator governor or reduce its load
When to escalate
If frequency is correct at the terminals and the alarm persists, escalate for inverter measurement-circuit service.
Fix it with the right tools
Check the system around the fault before replacing parts: load, battery bank, PV string and commissioning settings. If you need a second opinion, send the code and your inverter model to our team.
Before you open the inverter
- Isolate both the AC and DC sides, then confirm the display is dead before touching terminals.
- Use insulated tools and one hand where possible. DC arcs do not self-extinguish like AC.
- If you see burnt terminals, swollen cells, leaking electrolyte or a burning smell, stop and escalate instead of resetting the fault.
Questions installers ask
What does Felicity 36 mean?
Grid under-frequency alarm: grid frequency is below the inverter's permitted operating window.
How do I fix Felicity 36?
Wait for grid frequency to recover Correct the inverter frequency setting Service the generator governor or reduce its load
When should I escalate Felicity 36?
If frequency is correct at the terminals and the alarm persists, escalate for inverter measurement-circuit service.
Can I reset Felicity 36 myself?
Only after isolating the AC and DC sides and running the checks above. If Felicity 36 returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show Felicity 36?
Felicity 36 is documented for IVGM5-8K LP2G1 hybrid inverters (warning code list, flashing fault LED). Confirm the code on your own unit's display or manual before ordering parts.
More Felicity error codes
- Felicity 04Low cell voltage / over-discharge protection.
- Felicity 05PV over-current fault: the PV input current exceeded the inverter's PV input limit.
- Felicity 18PV short-circuit fault on the PV input; in the warning list the same number means battery under-voltage alarm.
- Felicity 19Battery open-circuit alarm: the inverter no longer detects a battery on its terminals.
- Felicity 20Battery SOC low alarm: the battery's state of charge has fallen to the low-SOC warning threshold.
- Felicity 21BMS communication alarm: abnormal communication between battery and inverter in non-SOC mode.
Guidance reviewed 17 October 2026 by the Mishka Energy installer team. Error codes vary by brand, model family and firmware; confirm against the manufacturer manual.
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