This could be due to the fact that your controller had protected cache after an unexpected power loss and your system was without power longer than the battery backup time.

其原因可能是发生意外断电后，系统处于断电状态下的时间长度已超过电池续用时间，控制器已保护高速缓存。

youdao

As backup power supply of the DC system, the residual capacity of battery effected safe operation of DC system directly when ac power failure occurs.

蓄电池作为直流系统交流停电时的后备电源，其剩余容量直接影响了直流系统的安全运行。

youdao

The abnormal failure of battery which works as the backup power supply for DC system when ac power failure occurs, will affect the safe operations of DC system seriously.

蓄电池作为直流系统交流停电时的后备电源，其非正常失效严重影响了直流系统的安全运行。

youdao

Peter Rive says SolarCity is putting the solar-battery backup system in 100 residential and commercial pilot projects.

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Monday morning around 5 am I was awoken by the scream of a carbon monoxide alarm in my centralized alarm system, letting me know the battery backup was failing.

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The microgrid comprises eight 100-kW grid-tied inverters, the rooftop PV array, the lead-acid battery pack, backup diesel generators, and a Web-based monitoring and control system.

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