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Solar · Error codes · SMA Solar Technology AG
8709SMA Solar Technology AG · Sunny Boy (SB 1.5-6.0)

8709 on a SMA Solar Technology AG Sunny Boy: Communication to the system control absent

Short answer

On a SMA Solar Technology AG inverter, 8709 means: Communication to the system control absent. 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.

Part involved: system manager / control communication.

When it shows: Communication to the system control absent.

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
SeverityWarning
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

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 24 September 2026