Series 90A annunciator provides reliable operation in hazardous locations, including petroleum, petrochemical and other process industries, consolidating the amount of control room equipment previously required. In addition to standard visual alarm display functions, the 90A timestamps alarms to determine the sequence of events, identifying the order in which alarms occur to establish the cause of a failure. The annunciator connects alarms to other equipment with the Modbus and DNP communications using either serial or Ethernet interfaces. It is easily configured through a software tool that places access to all features and functions just a mouse click away. The system is completely upgradeable and can be expanded if needed. LEDs aprovide visual indication of all alarms. The system performs self diagnostics, including serial/Ethernet communication status, lamp failure detect, ground fault detection in external wiring, and overall system status.