Common Acronyms; Register Specifications - 2100 Output - Teledyne 2105 Installation And Operation Manual

5.5 Common Acronyms

5.6 Register Specifications
- 2100 Output
Section 5 Modbus Protocol and 2100 Output
SCADA – SCADA (Supervisory Control And Data Acquisition)
is a computer system for gathering and analyzing real-time data.
SCADA systems are used to monitor and control plant operation,
or equipment in industries such as telecommunications, water
and waste control, energy, oil and gas refining, and transpor-
tation.
The SCADA system transfers the information (for example,
where a leak has occurred in a pipeline), back to a central site,
alerting the home station of the leak, performing necessary
analysis and control (such as determining if the leak is critical),
and displaying the information in a logical and organized
manner.
SCADA systems can be relatively simple, such as one that mon-
itors the environmental conditions of a small office building, or
very complex, such as a system that monitors all the activity in a
nuclear power plant or a municipal water system.
ASCII – American Standard Code for Information Interchange
DCS – Distributed Control Systems
MTU – Master Terminal Unit
OPC – Object Linking and Embedding (OLE) for Process Control
PLC – Programmable Logic Controller
RTU – Remote Terminal Unit
SCADA – Supervisory Control And Data Acquisition
TCP/IP – Transmission Control Protocol/Internet Protocol
All numbers in the Modbus registers are stored most significant
byte first. If the polling device has a byte ordering of least signif-
icant byte first (an Intel-based PC, for example), the bytes will
need to be reversed after they are received.
The Modbus ASCII address is used to index the data by modules.
Modbus ASCII address 1 contains information related to the site.
The first register contains a 16-bit integer count of the number of
modules that have data to report. The maximum number of
modules that can be supported is 4.
Modbus ASCII addresses 2 through the number of the module in
the stack (N) minus 1 contain data from the individual modules.
The Modbus ASCII addresses will be sorted by the model
number, and then by module name, which is entered by the user
through Flowlink. This allows the user to control the ordering of
the addresses and easily predict what data will be in specific reg-
isters. Every measured parameter has a corresponding status
and measurement time that are updated with each mea-
surement. The maximum number of supported measurements
from all modules in the system is 28.
2105 Interface Module
5-5