Echelon SmartServer 2.2 - Manual (Page 452)

SmartServer 2.2 User’s Guide 453
Field Name If the selected input point is a structured data point (has multiple fields) ,
select the field to be used in the selected function. For example, if the
selected input point has a SNVT_switch data type, you can use the value or
state fields of the data point in the function.
Unit Displays the unit string describing the data point to be updated. A
SNVT_temp_f#US data point, for example, has “degrees F” describing the
data point. A SNVT_switch data point has “% of full level” and “state
code” unit strings describing its state and value fields. This field is
read-only. You can edit the unit string of a data point in the Configure -
Data Points Web page, which you can access by clicking the data point in
General mode.
Poll Rate Displays the rate at which the Analog Functional Block polls the
SmartServer’s internal data server for updated data point values. The default
rate is 15 minutes. If the poll rate is set to 0, the data point will only be
updated when its value changes.
5. To configure the rate at which the Analog Functional Block polls the value of the selected data
points in the application, click the Poll Rate box for the data point. The Poll Rate dialog opens.
6. In the Poll Rate box, enter a value and then select a measurement of time (seconds, minutes, or
hours). The default poll rate is 15 minutes. To apply the specified poll rate to only the selected
data point, clear the Set Default Poll Rate check box. Click Close to return to the Analog
Functional Block: Data Points Web page.
7. Click Submit.
8. Click Back to return to the Analog Functional Block: Configure Web page.
9. In the Poll Delay On Restart box, specify the amount of time (in seconds) that the Analog
Functional Block waits after a reset before polling the values of the input data points. The default
value is 0, which means that the Analog Functional Block will resume polling the data points at
the poll rates specified in the Analog Functional Block: Data Points Web page.
10. Click Submit.
Selecting and Configuring a Mathematical or Logical Operation
You specify whether the Analog Functional Block performs a mathematical or logical function on the
selected input points. You can select a mathematical operation to determine the minimum, maximum,
average, or sum of two or more input points. You can use select a logical operation to compare the
value of one or more input points to that of a compare point, which can be another data point or a
constant value.