Installation manual

Glossary
190
Installing and Upgrading ENVOX r Configuration Software on DEC VAX and DEC AXP Systems (Revision B — May 1998)
configuration consists of responding to
prompts in a series of console screen
displays. For other PROVOX systems,
configuration consists of creating and
manipulating special ASCII text files.
Configuration Source File
A special ASCII text file that certain
PROVOX syste ms use fo r configuration.
Such a source file contains instructions
and reference information for the
contro llers and other devices in the
system.
Console Trend Display (CTD)
A PROVOX software product that collects
process operating data for continuous
contro l applications, then presents the
data in a graphical trend format o n the
operator console. CTD layers on CHIP
software.
Data
A general term that denotes any
information an MPU can process.
Database
A collection of data stored in a systematic
way so that searches and sorts are rapid
and so that retrieval of items is simple.
Database Index (DBI)
A sequential integer by which a computer
or other electronic device finds or keeps
track of storage locations in a database.
Datatype
Determines the rules that entries for
specific columns must follow.
DBI
Acronym: Database Index
DCL
Acronym: Digital Command Language
DDP
Acronym: Detail Display Parameter
Detail Display Parameter (DDP)
An item of information usually considered
changeable or tunable for a control loop
or point. Common examples are gain,
rate, reset, and alarm trip points.
Device
A piece of electronic hardware that
performs one or more prescribed
functions.
Discrete Control Device (DCD)
A PROVOX point type. A DCD point
encompasses as many as 8 discrete
output and 16 discrete input channels
into a single point. This makes possible
16 setpoints and matching input/output
states. A common use for a DCD point is
to control a discrete device that provides
feedback about its status. If the point
works with a DCD template, it can use
different combinations of channels at
different times during the execution of a
process-control algorithm.
Discrete Input (DI)
A PROVOX point type. A DI point
monitors a single discrete value of the
process variable. That is, a DI point reads
discrete data from a sensor or other
system device.
Discrete Output (DO)
A PROVOX point type. A DO point
generates a single discrete value
referenced by the setpoint.
Downlo ad
To transfer configuration instructions and
reference information from a
configuration device to other devices of a
process control system.
Glossary