Instruction manual

73
Low Alarm Limit
Type in the text box the process value below which you want a low alarm to occur.
Low-Low Alarm Limit
Type in the text box the process value below which you want a low-low alarm to occur.
Alarm Dead Band
Type in the text box the dead band to be used for each alarm set point.
Damping
Damping is applied to the input by taking a running average of the readings of the input signal
over the time frame specified by the damping setting (0-60 seconds)
. The averaged reading is
displayed and used for control. Type in the text box the desired time frame.
Backup Sensor Mode
The redundant sensor algorithm will allow the user to define a primary sensor to use for control
and a backup sensor. If the primary sensor goes invalid, the backup sensor will automatically take
over control, and the sensor error alarm will activate. If the sensors don’t match each other within
user-defined limits but both are valid readings, control will stop and a Sensor Deviated alarm will
activate. If the backup sensor goes invalid while the primary sensor is OK, control continues but
the sensor error alarm will activate. If both sensors are invalid, control stops and the sensor error
alarms activate.
To select this sensor as the backup sensor, click the Backup radio button, then click on the Submit
button at the bottom of the page. The page will reload showing the status of the sensor as Backup,
and offer additional menus:
Primary Sensor Assignment
This menu only appears if the Redundant Sensor Setting is Backup.
Use the pulldown arrow to select the sensor to use as the primary control sensor. All sensors of the
same type as the backup sensor will appear in the pulldown list.
Deviation from Primary Sensor
This menu only appears if the Redundant Sensor Setting is Backup.
Type the maximum allowable difference between the two sensor readings. If this deviation is
exceeded, then control of any outputs using the sensor will stop and an alarm activated.