Solar Lattice

Symptom

Battery error reported

ID
symptom:battery-error
IRI
https://solarlattice.org/kb/symptom/battery-error
Status
active
Also known as
Error in the battery

The Sunny Island shows a battery error as warning W945, or as error F929 at the higher level, when the external battery management reports a fault over SiCom. For errors reported over SiCom, find and clear the cause in the external battery management system, following the battery manufacturer's documentation. Other causes of a battery error include a timeout of the battery management link, a temperature above the manufacturer's upper limit, and external battery management that was detected but never configured. A battery error can also mean the battery has worn: its current capacity (SOH) is below 70%, or its measured voltage is out of range, possibly because aging has left too little usable capacity. The error can also appear when a battery protection mode is active, or after a state-of-charge recalibration that made a large jump. Check first that the data cable to the external lithium-ion battery is connected correctly, and that the battery's ambient conditions are within the manufacturer's limits. Then check that the error message is plausible, and replace the battery if needed.

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Claims

observed_as

c1 verified · fact Battery management error message

On Sunny Island, W945 (level 1 warning) and F929 (level 3 error) report an error in the battery that the external battery management sends over SiCom.

verified by: review-workflowverified on: 2026-10-23

c2 drafted · lead Battery voltage range message

A battery error can be raised when the battery voltage the Sunny Island measures is above or below the permissible measurement range.

c3 verified · fact Battery temperature status high

A battery error can be raised when the battery goes above the upper temperature limit approved by the battery manufacturer.

verified by: review-workflowverified on: 2026-10-23

Referenced by

Data