Status Instruments DM4000U, Руководство пользователя

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5.2.4 ERROR DETECTION
The instrument and the input is checked for a range of faults.
5.2.4.1 OPEN CIRCUIT
This is only checked for temperature sensors. If an open circuit is detected, the
process variable is forced full positive range or full negative range depending upon the
brnout setting in the Inputs menu. burn will be shown on the display in place of the
Process Variable display.
5.2.4.2 UNDER RANGE/ OVER RANGE
This is only checked for voltage or current inputs. If the input value is found to be
greater that 107% of full range, or less than -107% of full range, it is limited to 107%
or -107% of full range respectively. In this case, either
OVEr or UNdEr is shown on
the display instead of the process variable value. This condition will also occur if the
user nonlin conditioning is used and the input falls below the minimum entry or
exceeds the maximum.
5.2.5 OUTPUT CONTROL
The alarm Relays, LED alarms and current retransmission options may all use the
filtered, conditioned Process Variable Value. This is the same value which is
displayed.
This process responds to any errors detected. If the input is a temperature sensor, an
open circuit will invoke the burnout condition, going to hi scale or low scale
depending upon the burnout programming.
5.6 DISPLAY
This will show the Process Variable in engineering units, filtered and conditioned. If
any errors have been detected, they will be indicated on the display. The number of
places of decimal will be as defined in the
rES entry of the inputs menu, but if there
are more significant digits than can be displayed within the five digit field
available, the number will be right justified
. For example 1234.567 will be
displayed as 1234.57. Although the electrical input is updated ten times a second, the
display is updated at the more visually practical rate of three times a second.
OPERATION
INSTRUMENT OPERATION
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