44 NFS-320/E/C, NFS-320SYS/E Operations Manual — P/N 52747:E1 06/16/2011Read Status Operation Viewing and Printing a Read Status4.4.2 How to View Read Status for Event and Alarm HistoryOverviewThe control panel maintains a History buffer of the last 800 events, each with a time and datestamp. History events include the following:• All alarms, troubles and operator actions, such as: Acknowledge, System Reset, SignalSilence, Drill, and Walk Test.• Programming entries (Program Change and Status Change, but not Read Status), along with anumber (0-9) indicating the programming submenu (for example, 0=Clear). For an example,see Figure 4.18.You can view events from the History buffer in two forms: by displaying all events (option 2,HIST=2) or by displaying alarm events only (option 4, ALARM HIST=4).How to View Read Status for Event HistoryOption 2 (HIST =2) lets you view the total number of events in the Historybuffer (up to 800 events), then view each event in chronologicalsequence. From the “Read Status” screen, press 2, then press the ENTERkey to display the “Event History” screen. A sample of the Event Historyscreen is shown below:Figure 4.16 Sample Event History DisplayTo display events in the History buffer, do the following:• Press the NEXT SELECTION key to step through each event from the first entry (oldest eventfirst) in the History buffer, or• Press the PREVIOUS SELECTION key to step through each event from the most recent entry in theHistory buffer.A sample LCD display for a trouble event:Figure 4.17 Sample Trouble Event DisplayNOTE: The History buffer contains 800 events total, including the alarm events that display forAlarm history. The control panel generates Alarm history from the alarm events that exist in the800-event History buffer.next eventprevious eventThe number of events in the History bufferE V E N T H I S T O R Y S T A R TE V E N T S I N H I S T O R Y : 5 5 0NOTE: The NEXT SELECTION key will show the most recent event first, and then move to itsnormal function of displaying the oldest events first.Time and date of the eventType of troubleType of eventT R O U B L I N S Y S T E M G R O U N D F A U L T0 1 : 4 6 P 0 1 1 5 0 8 T u e