Section 3 - Glossary Of Scada Terms - QEI ePAQ-9150 User Manual

ePAQ-9150
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Section 3 – Glossary of SCADA Terms
This section provides a list of the microcomputer and supervisory control terms that
are used throughout the Remote Terminal Unit Subsystem's User's Manual. Some of
the terms have standard usage throughout the industry, while others are defined as
expressly used by QEI. The glossary may be regarded as a definitive reference only
within respect to the usage of the terms within this manual.
All words, abbreviations, and mnemonics are listed in alphabetical order.
Accumulation
Accumulator Point
Activated Remote
A/D or ADC
A/D Converter
Address
Address Bus
Alarm
Analog Point
Aperture Time
APPRS
APPR Level
ASCII
Asynchronous
Authorized Change
Copyright © 2016 QEI
A measurement whose raw value is generated by a pulse count and is
presented in analog form.
A measurement point whose value is obtained by counting the number of
contact closures appearing at a status input.
An online remote station that is being polled for data by the master station
and is responding to commands.
Analog-to-Digital, such as an A/D Converter.
Analog-to-Digital Converter. A device that converts an analog input to a
binary or BCD output.
A location, either in hardware or within the program. Hardware addresses
always consists of binary numbers while program addresses may be
numbers or names.
A path for the transfer of several address bits in parallel.
A condition, defined by the customer, that represents an unauthorized
change of a status point; a measurement point with a value out of limits,
or any other system condition that requires operator notification and
acknowledgement.
A measurement point whose raw value is derived from a voltage or
current received from a transducer or other device.
A time span during which a selected point must be commanded. At all
other times, the master station automatically refuses the control operation.
Automatic peak-power reduction system. An optional SCADA program
that provides for automatic voltage reduction at all remote stations as a
function of the total demand as computed at the master station.
The number, entered via the control keyboard, around which the
(optional) automatic peak-power reduction system operates.
See USASCII.
Method of receiving serial data, without the use of transmitted clock
pulses, in which synchronization is achieved by a start bit at the beginning
of the word and a stop bit at the end of the word.
Any change in the status of a system point that results from a command
Remote Terminal Unit
Section 3 – Glossary
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