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ROC800-Series Instruction Manual
A-2
Glossary
Revised Jul-14
C
(continued)
COMM
Communications port on a ROC used for host communications. .
Note
: On FloBoss 500-Series and FloBoss 407s, COMM1 is built-in for RS-232 serial
communications.
Comm Module
Module that plugs into a ROC to provide a channel for communications via a specified
communications protocol, such as EIA-422 (RS-422) or HART.
CF
Compare Flag; stores the Signal Value Discrete (SVD).
Configuration
Refers either to the process of setting up the software for a given system or the result
of performing this process. The configuration activity includes editing the database,
building schematic displays and reports, and defining user calculations. Typically, the
software setup of a device that can often be defined and changed. Can also mean the
hardware assembly scheme.
Configuration
Tree
In ROCLINK 800, the graphical display that appears when a configuration file opens. It
is a hierarchical branching (“tree-style”) method for navigating within the configuration
screens.
CPU
Central Processing Unit.
CRC
Cyclical Redundancy Check error checking.
Crosstalk
The amount of signal that crosses over between the receive and transmit pairs, and
signal attenuation, which is the amount of signal loss encountered on the Ethernet
segment.
CSA
Canadian Standards Association. See
http://www.csa.ca.
CSMA/CD
Carrier Sense Multiple Access with Collision Detection.
CTS
Clear to Send modem communications signal.
D
D/A
Digital to Analog signal conversion.
DB
Database.
dB
Decibel. A unit for expressing the ratio of the magnitudes of two electric signals on a
logarithmic scale.
dBm
Power ratio in decibels (dB), referenced to one milliwatt (mW), also known as dBmW.
DCD
Data Carrier Detect
modem communications signal. In addition,
Discrete Control
Device
– A discrete control device energizes a set of discrete outputs for a given
setpoint and matches the desired result against a set of discrete inputs (DI).
DCE
Data Communication Equipment.
Deadband
A value that is an inactive zone above the low limits and below the high limits. The
purpose of the deadband is to prevent a value (such as an alarm) from being set and
cleared continuously when the input value is oscillating around the specified limit. This
also prevents the logs or data storage location from being over-filled with data.
Device
Directory
In ROCLINK 800, the graphical display that allows navigation through the PC Comm
Ports and ROC Comm Ports setup screen.
DI
Discrete Input.
Discrete
Input or output that is non-continuous, typically representing two levels (such as on/off).
DMM
Digital multimeter.
DO
Discrete Output.
Download
The process of sending data, a file, or a program from a PC to a ROC.
DP
Differential Pressure.
DRN
Distributed RTU Network, in which two or more remotely distributed RTU devices
(RRTUs) are wirelessly connected in a peer-to-peer network to share data.