SMA Error Codes
Frequent SMA Sunny Boy and Tripower event codes, what triggers them, and the difference between a momentary grid event and a real fault.
- Manufacturer
- SMA
- Codes documented
- 25
- Source
- SMA manuals & field references
- Scope
- Reference only
An independent reference compiled by Solar Analytica from SMA documentation and field sources. SMA reports faults as numbered event codes on the inverter display or in Sunny Portal / SMA 360°. This covers the common operational codes; SMA defines hundreds in total (including battery, network, and firmware-update events). Note: the insulation and residual-current events (3501, 3701) can latch on some Sunny Boy models and block restart even after the fault is fixed — once an installer has repaired the cause, they're cleared via Sunny Portal (SMA advises no more than once per day). Safety: a DC over-voltage (3401) can destroy the inverter — switch off the DC isolator and call your installer; insulation, residual-current, and earth faults are licensed-installer work.
- 25 SMA fault and alarm codes, documented in plain English.
- Compiled from manufacturer documentation — independent and not affiliated with SMA.
- Codes involving DC/AC isolators, wiring or opening the unit are licensed-electrician work — when in doubt, call your installer.
25 of 25 codes
- 101 · 102 · 103 · 105
Grid voltage / impedance too high
The grid voltage or grid impedance at the inverter's connection point is too high, so it disconnects.
What to do
Usually a network issue rather than a faulty inverter. Confirm the country dataset is correct and the grid voltage is in range; if it's frequently high, contact your installer or network operator. It self-restores when voltage returns to range.
- 202 · 203 · 205
Grid disconnected / voltage too low
The grid has been disconnected, the AC cable is damaged, or the grid voltage is too low.
What to do
Check the AC circuit breaker / main switch is on and the grid is present. If the grid is fine and it persists, have an installer inspect the AC cable and connections.
- 301
10-minute average voltage out of range
The ten-minute average grid voltage is outside the permissible range.
What to do
Monitor the grid voltage during operation. If it's persistently out of range due to local conditions, contact your network operator.
- 302
Power reduced — high AC voltage
The inverter has reduced its output because the grid voltage is high (Volt-Watt response, to support grid stability).
What to do
Expected behaviour when grid voltage is high, not a fault. If it happens often it's costing you generation — your network voltage is high; contact your installer or network operator.
- 401 · 404
Islanding / frequency change
A stand-alone (islanded) grid or a very large change in grid frequency was detected.
What to do
Usually a short-term grid event that self-clears. If it recurs, have your installer check the grid connection for frequency fluctuations.
- 501
Grid frequency out of range
The power frequency is outside the permissible range.
What to do
Monitor the frequency. If fluctuations are frequent — common on a backup generator — contact your network operator.
- 601
Excess DC in grid current
The inverter detected an excessively high proportion of direct current in the grid current.
What to do
If it recurs, contact your installer; the grid operator may need to raise the monitoring threshold, or the inverter may need a service check.
- 901
Grounding (PE) connection missing
The protective-earth (grounding) conductor is not correctly connected.
What to do
An electrical-safety fault — have a licensed electrician or installer check the earth connection against the installation manual. Don't keep resetting it.
- 1001
Line and neutral swapped
The L (active) and N (neutral) connections are swapped.
What to do
A wiring fault — have your installer correct the L and N connections per the installation manual.
- 1302
Waiting for grid voltage
L or N is not connected (or an AC conductor is damaged) — often simply a mains outage.
What to do
If there's a power cut, it clears when supply returns. Otherwise check the AC main switch is on and the breaker hasn't tripped; if it persists, have an installer check the AC conductors.
- 1501
Reconnection fault (country dataset)
A changed country dataset or parameter value doesn't match local requirements.
What to do
Your installer should verify the correct country standard is configured (the “Set country standard” parameter).
- 3301 · 3302 · 3303
Unstable operation (low DC)
There isn't enough power at the DC input for stable operation.
What to do
Often just low light, shading, or snow on the array. Check the panels are clear and the array is error-free; if it persists in good sun, contact your installer.
- 3401 · 3402 · 3407
DC over-voltage
Over-voltage at the DC input — this can destroy the inverter.
What to do
Switch off the DC isolator and contact your installer immediately. The DC input voltage is above the inverter's maximum — the string is likely sized too long and must be corrected by a professional before reconnection.
- 3501
Insulation failure (ground fault)
A ground fault / low insulation resistance detected on the DC (PV) side — safety-critical, and common in wet weather.
What to do
An installer must check the PV array and DC cabling for ground faults. On some Sunny Boy models this latches — after the fault is repaired it's cleared via Sunny Portal (no more than once a day). Don't keep resetting it.
- 3701
Residual current too high
The inverter detected an excessive residual (earth-leakage) current — an electric-shock hazard.
What to do
An installer must check the PV array and DC cabling for ground faults. Like 3501 it can latch and is cleared via Sunny Portal after repair (max once per day). Treat it as safety-critical.
- 3801 · 3802 · 3805
DC over-current
Over-current at the DC input; the inverter briefly interrupts feed-in.
What to do
If it's frequent, have your installer verify the PV array is correctly rated and wired (and check for a short circuit).
- 3901 · 3902
Waiting for DC start conditions
The conditions for feeding into the grid aren't yet met — typically insufficient irradiation.
What to do
Normal early/late in the day. Make sure the array isn't covered or shaded; if it persists in good sun, contact your installer.
- 6501 · 6502 · 6509
Over-temperature
The inverter has switched off (or derated) due to excessive temperature.
What to do
Clear dust from the cooling fins and air ducts, ensure good ventilation, and keep the ambient temperature within limits (and the unit out of direct sun). If it persists, contact your installer.
- 6512
Minimum operating temperature not reached
It's too cold — the inverter only resumes feed-in once the temperature reaches at least −25 °C.
What to do
No action needed; it resumes automatically as the temperature rises.
- 7500 · 7501
Fan fault
A cooling fan is not functioning properly.
What to do
Check the fan area for blockage. If the fan is faulty it needs service — contact your installer or SMA Service.
- 7701 · 7702 · 7703
Grid relay defect
The grid disconnection relay is defective or failed its test.
What to do
A hardware fault — contact SMA Service or your installer. If shown only occasionally, note whether it recurs.
- 8003
Power reduced — temperature
The inverter has reduced output for more than ten minutes because of excessive temperature.
What to do
Clean the cooling fins and air ducts, ensure adequate ventilation, and keep the ambient temperature within the rated limit. If it recurs, contact your installer.
- 9002
Grid Guard code invalid
The SMA Grid Guard code entered is incorrect, so the protected operating parameters stay locked.
What to do
An installer-level message — enter the correct SMA Grid Guard code. Not something a homeowner needs to action.
- 9003
Grid parameters locked
Changes to the grid parameters are now blocked (they require the Grid Guard code).
What to do
Informational. To change protected parameters, an installer logs in with the Grid Guard code.
- 9007
Self-test aborted
The inverter's self-test was terminated.
What to do
Check the AC connection is correct and restart the self-test. If it keeps aborting, contact your installer.
Frequently asked
- Where do these SMA fault codes come from?
- We compile them from publicly available SMA inverter documentation and field references, then rewrite each entry in plain English. Solar Analytica is independent and not affiliated with SMA.
- Can I clear these faults myself?
- Some clear automatically once conditions return to normal. Anything involving DC isolators, AC switches, wiring or opening the unit is licensed-electrician work — if in doubt, contact your installer rather than working on a live system.
- My exact code isn't listed — why not?
- Firmware and model variants differ, and manufacturers occasionally revise their codes. We document the most common ones; if yours isn't here, check your inverter's manual or ask your installer.
- How current is this reference?
- Last reviewed June 2026. We revise it when the underlying manufacturer documentation changes.
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