6502 on a SMA Solar Technology AG Sunny Boy: The inverter has switched off due to excessive temperature
Short answer
On a SMA Solar Technology AG inverter, 6502 means: The inverter has switched off due to excessive temperature. The inverter stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: The inverter has switched off due to excessive temperature.
Part involved: inverter overtemperature.
When it shows: The inverter has switched off due to excessive temperature.
Likely causes:
- SMA corrective measures: Clean the cooling fins on the rear of the enclosure and the air ducts on the top using a soft brush. Ensure that the inverter has sufficient ventilation. Ensure that the inverter is not exposed to direct solar irradiation. Ensure that the maximum permissible ambient temperature is complied with.
Is it safe?
| Does the inverter stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The inverter stops until the fault clears or is reset.
Resetting itself: yes.
Manual reset: Automatic when condition clears.
What you can check
- Read the event number and message in the SMA Energy app / Sunny Portal (ennexOS) or the inverter's web interface and note the date/time for your installer. A red LED on the inverter means an event has occurred.
- Check nothing is stacked against, covering or boxing in the inverter and that it is not in direct sun in an enclosed space; keep the area around it clear.
- If it happens once and the inverter resumes feeding in on its own, no action is needed; if the event keeps recurring, contact your installer.
What the engineer will check
- Clean cooling fins and air ducts with a soft brush; verify clearances, ventilation, shading from direct sun and max ambient temperature.
Who to ask for: PV installer.
Certification: Qualified electrician (BS 7671; MCS-certified PV installer for work on the PV array/DC side).
What you might notice
Sources
- Operating manual SUNNY BOY 3.0/3.6/4.0/5.0/6.0 ↗ · SBxx-1AV-41-BE-en-21 Version 2.1 · page 97 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026