Rosemount FISHER-ROSEMOUNT 244EH, Руководство по эксплуатации продукта

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3-5
Viewing the Process
Variable
With version 2.0 and later of the Model 244EC Configuration Interface,
users can view the measured temperature (PV) by selecting
SERVICE
from the menu bar of the main configuration window (see Figure 3-2).
In order to view a valid PV, a temperature sensor must be connected to
the Model 244E transmitter, and the transmitter must be configured
properly for that sensor type. The PV will be automatically updated on
the Model 244EC screen approximately two times per second.
Figure 3-2. Viewing the Process
Variable with the 244EC
INTERMITTENT SENSOR
ALGORITHM
The electronics of the Model 244E transmitter contains an intermittent
sensor algorithm that monitors the input signal during operation. The
signal diagnostics routine, which occurs at each temperature update
(every 500 milliseconds), eliminates output pulsing in an intermittent
open sensor condition. Further, it validates the input signal before the
digital-to-analog (D/A) conversion takes place.
If the process temperature changes, the intermittent sensor algorithm
causes the transmitter to respond according to one of the three cases
described below.
Threshold value is the maximum change in reading (as
a percentage of output range) within one update cycle (500 ms). The
threshold value of the Model 244E is 2% of output range.
244
E
-24
4E
C
0
1