Emerson Rosemount 3308A Reference Manual page 187

Reference Manual
00809-0100-4308, Rev CA
Lost measurement
Lost measurement behavior
Configure level value to report if measurement is lost unexpectedly. Choose one of the following actions:
Table D-5. Lost Measurement Behavior Options
Option
Alarm (NaN Value/Bad Status)
Output Full Tank
Output Empty Tank
Number of measurements to hold level
The number of measurements the device will hold the current level if level measurement has been lost.
Then it will output level according to Lost Measurement Behavior, if still lost.
For an application where problems with lost measurement due to noise or weak surface echoes are
experienced, this parameter value could typically be increased.
The Hold Time value presents for how long the device will hold the current level. The time the current
level will be held is calculated out of a combination of both Number of Measurements to Hold Level and
the Update Rate.
Note
Make sure you have enough safety margin in your system to manage a delayed condition.
Configuration Parameters
PRELIMINARY
Description
If the measurement is lost, the level value will report:
"Not a Number / Bad Status".
If the measurement is lost, the level value will correspond to full tank.
If the measurement is lost, the level value will correspond to empty tank.
Configuration Parameters
August 2017
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