This is the free-text human-readable description accompanying a specific alarm entry, giving a technician plain-language context about what exactly triggered the alarm beyond what the numeric tsiAlarmType and tsiAlarmSource fields alone convey. For actually understanding and resolving an alarm without needing to cross-reference a separate vendor fault-code table, the string itself should explain the condition in terms a technician can act on directly. A technician reading this field might see text like Module 3 DC input voltage below threshold rather than needing to decode a bare numeric event code from tsiModuleDCInStatus.