Operation state of the site AC input breaker. It is an enumeration type:
If the enumeration value is 1, it indicates that the site AC input breaker is in the normal state;
If the enumeration value is 2, it indicates that the AC input breaker disconnect;
If the enumeration value is 254, it indicates AC input breaker alarm resume;
If the enumeration value is 255, it indicates AC input breaker operation status unknown.