Справочник Пользователя для Emerson Process Management 3420

June 2013

3-9000-743 Rev S

6.6.4

Alarm log

The Mark III meter monitors several data points with respect to each point’s alarm limit(s). Non-
boolean data points can have low and high alarm limits. Boolean data points only have a single 
alarm limit (i.e., either TRUE or FALSE). There are two statuses associated with alarms: set and 
cleared. An alarm is set when the data point is at or exceeds its alarm limit. An alarm is cleared 
when the data point is within its alarm limit(s).

The Mark III meter stores an alarm log record whenever any monitored data point’s alarm status 
(cleared or set) changes. The alarm log record indicates the data point, date and time, alarm 
status, corresponding alarm limit, and data point value.

The meter can store up to 3000 alarm records. The user can select whether old, unread records 
can be overwritten by new records when the log becomes full via the data point 

DoOverwriteUnreadAlarmLog. This point can be modified using the Daniel MeterLink Tools - 
Edit/Compare Configuration

 screen. The default is to overwrite old, unread records. Refer to 

 for information on reading records and marking records as read. The data point 

IsAlarmLogFull indicates whether or not the alarm log is full and cannot overwrite old, unread 
records.

The user-settable data points 

AlarmTurnOffHysterisisCount and AlarmTurnOffHysterisis-

TimeSpan are used to prevent very repetitive alarms from filling up the alarm log. When an 
alarm is set 

AlarmTurnOffHysterisisCount times within AlarmTurnOffHysteresisTimeSpan 

seconds, then the alarm is suppressed until the alarm frequency drops below the specified rate 
(counts per time span) at which point the next alarm clearing “unsuppresses” the alarm. The 
alarm log records indicate when an alarm suppression is started and ended. The default values 
are 8 occurrences in 240 seconds.

The data points monitored for the alarm log are as shown in 

 and 

 below. 

Note that the alarm limits are themselves data points. The user-settable alarm limits are listed 
by data point name. Non-settable alarm limits are listed by data point value.

GainAUp, GainADn,

GainBUp, GainBDn,
GainCUp, GainCDn,
GainDUp, GainDDn

GainLowLmt

GainHighLmt

AvgSndVel

AvgSoundVelLoLmt

AvgSoundVelHiLmt

AGA8BaseCalcStatus

1

AGA8FlowCalcStatus

1

SpecFlowPressure

LowPressureAlarm

HighPressureAlarm

SpecFlowTemperature

LowTemperatureAlarm

HighTemperatureAlarm

LiveFlowPressure

LowPressureAlarm

HighPressureAlarm

LiveFlowTemperature

LowTemperatureAlarm

HighTemperatureAlarm