29252 on a SMA Solar Technology AG Sunny Boy Smart Energy: SPS mode is not started because the connection to the utility grid is still active

What it means

The manual says: SPS mode is not started because the connection to the utility grid is still active.

Part involved: secure power supply / backup operation.

When it shows: SPS mode is not started because the connection to the utility grid is still active.

Likely causes:

• SMA corrective measures: Verify that the utility grid is down or that the AC power supply to the inverter has been disconnected using the AC circuit breaker. Ensure that the parameter settings for backup operation are properly configured.

Is it safe?

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.
• Backup starts only when the grid is actually down; check backup settings with your installer.

What the engineer will check

• Check backup/SPS parameter settings; confirm AC disconnection detection.

Who to ask for: Battery installer.

Certification: Qualified electrician competent in battery energy storage (IET Code of Practice for Electrical Energy Storage Systems); manufacturer-trained installer.

What you might notice

• Error code shown on inverter or app

Sources

• Operating manual SUNNY BOY SMART ENERGY 3.6/4.0/5.0/6.0/8.0/9.9 ↗ · SBSExx-50-BE-en-12 Version 1.2 · page 103 · Reviewed 24 September 2026

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

Reviewed: 24 September 2026