8708 on a SMA Solar Technology AG Sunny Boy: Communication to the system control absent. Depending on the fallback setting, either the last received values will be retained or the active power will be limited to the set percentage value of the inverter nominal power
Short answer
On a SMA Solar Technology AG inverter, 8708 means: Communication to the system control absent. Depending on the fallback setting, either the last received values will be retained or the active power will be limited to the set percentage value of the inverter nominal power. The inverter keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 24 September 2026 · 1 source
What it means
The manual says: Communication to the system control absent. Depending on the fallback setting, either the last received values will be retained or the active power will be limited to the set percentage value of the inverter nominal power.
Part involved: system manager / control communication.
When it shows: Communication to the system control absent. Depending on the fallback setting, either the last received values will be retained or the active power will be limited to the set percentage value of the inverter nominal power.
Likely causes:
- SMA corrective measures: Ensure that the connection to the System Manager is intact and that no cables are damaged or that no plugs have been pulled.
Is it safe?
| Does the inverter stop? | Partly |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The inverter keeps running with some functions stopped.
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 your home Wi-Fi/router is working and the SMA app/Sunny Portal can see the system.
- Check any SMA Data Manager / Home Manager is powered and its network cable is plugged in (do not open anything).
What the engineer will check
- Check connection to System Manager, cabling and plugs; confirm fallback setting (active power may be limited to set percentage).
Who to ask for: PV installer / monitoring.
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 102 · Reviewed 24 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 24 September 2026