Notifier UniNet 2000, Инструкция по установке, эксплуатации и администрированию

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92 The Workstation Installation/Operation Manual Version 2 Document 51540 Rev. B1 4/8/02
The Analog Input Device dialog is divided into two areas, the Device Assignment Area and the Device
Testing Area . The display style and performance of the device are defined in the assignment area. Then, its
performance can be manually demonstrated in the testing area to verify expected performance before finishing the
assignment.
Device Assignment Area
The device assignment area allows the definition of three basic parameters:
• Range Translation.
• Alarm Thresholds.
• Report Frequency.
Range Translation - The analog device configuration form allows configuration of a range translation
between what is reported by the analog device and what is annunciated and interpreted by the workstation. The
translation portion of the form shows the native values and units. Below this, a space is provided to enter a new
range of values and to specify the new units. The software will automatically perform this translation. All values
displayed in the analog configuration refer to the converted range, not the native range. If a new range is entered
and a threshold point is not within that range, then an error message will be displayed to alert the user of this. In
addition, if a threshold is out of range, it is displayed over a red background instead of a green background.
Alarm Thresholds
- These fields allow alarm points to be inserted at different levels in the device's reporting
range. When an analog value is reported for a device it is compared to the assigned alarm thresholds. If the
reported value falls between the first low and first high threshold the device remains in a normal state. As the value
rises and falls it will cause an alarm state in the device when it passes a threshold value. Therefore, reaching the
threshold will not cause a change of state.
Six threshold levels can be assigned:
• Very High.
• Higher.
• High.
• Low.
• Lower.
• Very Low.
Three parameters must be configured for each alarm threshold:
• Threshold value - This is a numeric value for comparison to the adjusted reporting value. The threshold
can be configured using the blue handles to the side of the threshold scale. Moving these handles within
the range allows quick setting of an alarm point. If a threshold value is out of range, it will be displayed in
a red field instead of a green field.
• Alarm message - Descriptor for the related alarm state. This message is displayed above the device
icon, and is reported as an event when the specified threshold is crossed.
• Device Symbol - Click on the
Browse
button to open the device library and select a graphic symbol
for each alarm state and the normal condition. Seven must be selected. A variety of device symbols for
gauges and scales in different states are available. Custom symbols can also be created. For more
information on creating custom symbols, refer to the section 3.4.9 Creating Device Symbols.
Report Frequency - A Report Frequency is set for both normal and off-normal conditions for each analog
device. These values represent the amount of time in seconds between each update of the current analog value of
the device. Different frequencies can be specified for both off-normal and normal conditions to allow more
frequent reporting during problematic situations.
NOTE: All thresholds must be entered as converted display values and
are compared to reported values after they have been adjusted by the
range translation.
Figure 3-22: The Analog Device
Address
Symbol
Reported Value
(Adjusted)
Device State