Emerson Process Alarms, Alarm Priority, Status Options, Rosemount 3051S, Reference Manual

Reference Manual

00809-0200-4801, Rev BA April 2007

Rosemount 3051S

Process Alarms

Process Alarm detection is based on the OUT value. Configure the alarm limits of the following standard alarms:

•High (HI_LIM)

•High high (HI_HI_LIM)

•Low (LO_LIM)

•Low low (LO_LO_LIM)

In order to avoid alarm chattering when the variable is oscillating around the alarm limit, an alarm hysteresis in percent of the PV span can be set using the ALARM_HYS parameter. The priority of each alarm is set in the following parameters:

•HI_PRI

•HI_HI_PRI

•LO_PRI

•LO_LO_PRI

Alarm Priority

Alarms are grouped into five levels of priority:

Priority
Number	Priority Description

0The alarm condition is not used.

1An alarm condition with a priority of 1 is recognized by the system, but is not reported to the operator.

2An alarm condition with a priority of 2 is reported to the operator.

3-7 Alarm conditions of priority 3 to 7 are advisory alarms of increasing priority.

8-15 Alarm conditions of priority 8 to 15 are critical alarms of increasing priority.

Status Options

Status Options (STATUS_OPTS) supported by the AI block are shown below:

Propagate Fault Forward

If the status from the sensor is Bad, Device failure or Bad, Sensor failure, propagate it to OUT without generating an alarm. The use of these sub-status in OUT is determined by this option. Through this option, the user may determine whether alarming (sending of an alert) will be done by the block or propagated downstream for alarming.

Uncertain if Limited

Set the output status of the Analog Input block to uncertain if the measured or calculated value is limited.

BAD if Limited

Set the output status to Bad if the sensor is violating a high or low limit.

Uncertain if Man Mode

Set the output status of the Analog Input block to uncertain if the actual mode of the block is Man.

NOTES

The instrument must be in Out of Service mode to set the status option.

3-15