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Glossary
Falling edge
Transition of the input signal from high to low.
Hexidecimal
In mathematics and computer science, hexadecimal (or hex) is a numeral system
with a radix, or base, of 16. It uses sixteen distinct symbols, most often the symbols
0–9 to represent values zero to nine, and A, B, C, D, E, F (or a through f) to represent
values ten to fifteen.
LSW
Least Significant Word. Unit of data with the low-order bytes at the right.
Master/slave
Master/slave is a model of communication where one device (Master) or process has
unidirectional control over one, or more, other devices. In some systems a master is
elected from a group of eligible devices, with the other devices acting in the role of
slaves.
Modbus
Modbus is a serial communications protocol published by Modicon in 1979 for use
with its programmable logic controllers (PLCs). It has become a de facto standard
communications protocol in industry, and is now the most commonly available
means of connecting industrial electronic devices. Modbus allows for communication
between many devices connected to the same network, for example a system that
measures temperature and humidity and communicates the results to a computer.
Modbus is often used to connect a supervisory computer with a remote terminal unit
(RTU) in supervisory control and data acquisition (SCADA) systems.
MSW
Most Significant Word. Unit of data with the high-order bytes at the left.
PhaseChek™
PhaseChek is a unique feature of the PowerScout™ and greatly simplifies installation
and, at a glance, verifies correct CT orientation during installation. The PowerScout
automatically adjusts for CT orientation—greatly reducing set-up time and all but
eliminating installation errors. It is common for an individual phase power factor to
be less than 0.55 and the corresponding LED will be red.
Power Factor
The power factor of the AC electric power system is defined as the ratio of the real
power flowing to the load to the apparent power, and is a number between 0 and 1
(frequently expressed as a percentage, e.g. 0.5 pf = 50% pf). Real power is the
capacity of the circuit for performing work in a particular time. Apparent power is
the product of the root mean squared current and root mean squared voltage of the
circuit. Due to energy stored in the load and returned to the source, or due to a non-
linear load that distorts the wave shape of the current drawn from the source, the
apparent power can be greater than the real power.
Rising edge
Transition of the input signal from low to high.
RMS
Root-Mean-Square. True RMS is the AC voltage/current that produces the equivalent
amount of heat in a resistor as a DC voltage/current, whether sinusoidal or not. All
DENT Instruments meters measure true RMS.
RS-485
EIA-485 is used as the physical layer underlying many standard and proprietary
automation protocols used to implement Industrial Control Systems, including
modbus.
Summary of Contents for PowerScout 3
Page 19: ...15 Figure IV 1 Single Phase Two Wire N white L1 black L2 red L3 blue ...
Page 20: ...16 Figure IV 2 Single Phase Three Wire N white L1 black L2 red L3 blue ...
Page 21: ...17 Figure IV 3 Three Phase Three Wire Delta N white L1 black L2 red L3 blue ...
Page 22: ...18 Figure IV 4 Three Phase Four Wire Wye N white L1 black L2 red L3 blue ...
Page 23: ...19 Figure IV 5 Three Phase Four Wire Delta N white L1 black L2 red L3 blue ...
