Specifications

Glossary
Glossary - 16
timer
A timer is a programming mechanism for running scripts at regular intervals in Station.
Trend Set
A set of point parameter historical data, usually shown as a graph on a standard Station
display. Trend sets can be defined using Quick Builder or a Station display.
UDC
Universal Digital Controller.
Unreasonable High and Unreasonable Low alarms
Alarms configured for an unreasonably high value and an unreasonably low value for
the PV of an analog point.
URL
Uniform Resource Locator. For example, a Web address.
User Scan Task controller
A server software option used to configure a server database table (called a “user file”)
to act as a controller. The server interfaces with the user file rather than the actual
device.
In this way you can write software to interface with the server and to communicate with
devices that are connected to, but not supported by, the PlantScape server. The
PlantScape server can then scan data from the user files into points configured on the
User Scan Task controller and, for control, the PlantScape server can write point control
data to the user file or a control queue.
utility
PlantScape programs run from a command line to perform configuration and
maintenance functions; for example, the lisscn utility.
virtual controller
See User Scan Task controller.
WINS
Windows Internet Name Service.
WWW
World Wide Web.
plscpcg.book Page 16 Monday, May 28, 2001 10:11 AM