Specifications
Glossary
PlantScape Server and Client Configuration Guide Glossary - 11
There are two types of point algorithms, PV (processed every time the point parameter
is scanned) and Action (processed only when a point parameter value changes).
Point Detail display
A display that shows the current point information. Each point has a Point Detail
display.
Process software
An umbrella term for Control Builder and other process software.
process variable
An actual value in a process: a temperature, flow, pressure, and so on. Process variables
may be sourced from another parameter and may also be calculated from two or more
measured or calculated variables using algorithms. Status points have a PV of the
current state (0 to 7) (eight possible states).
programmable logic controller (PLC)
A control and monitoring unit that connects to a field device and controls low-level
plant processes with very high-speed responses. A PLC usually has an internal program
that scans the PLC input registers and sets the output registers to the values determined
by the program. When connected to the server, the input and output values stored in
the PLC registers can be referenced, and the server can read and write to these memory
addresses.
project
In Quick Builder, a working database file that enables you to make changes to the
server database without affecting the configuration data that is currently being used to
run the system.
project view
In Quick Builder, a window in which you can view, add, and modify any items in the
current project file.
PV
PlantScape abbreviation for process variable.
PV algorithm
One of two types of algorithm you can assign to a point in order to perform additional
processing to change point parameter values. A PV algorithm changes the value of the
point process value (PV) input only. Contrast with Action algorithm.
PV clamp
For an analog point, a configuration that will immobilize the process value (PV) at 0% if
it falls below the entry low limit value or at 100% if it goes above the entry high limit
value.
plscpcg.book Page 11 Monday, May 28, 2001 10:11 AM