From Industrial Data Communications 4th Edition

In the text we look at the way data is represented (a set of patterns referred to as “1” or
“0”) generally in a set of these patterns called an octet or a byte (or sometimes a character
when referring to text), and we have looked at the abstraction of a model to see the functions
required to move these data representations from one end user to another. We will
now look at another of the fundamentals of communications, the medium over which we
transmit those data representations, the very bottom of the OSI Model, the media. This is the
location where the Physical layer attaches to the outside world, the conduit for information.

All things in data communications are related, and if they are all not correct you do not
communicate very well. Sometimes called pipes, the media is the main constraint on data
transfer speed. There are three types of media in general we will discuss, these are: the
copper types, fiber-optic types, and wireless types. Since this probably covers all media normally
used, that isn’t too restrictive. Of the copper types, three generally come to mind in
the LAN and industrial areas: the Unshielded Twisted Pair (UTP),...

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Products & Services
HVAC Fans and Blowers
HVAC fans and blowers are used to move air through heating, ventilating, and air conditioning (HVAC) systems. They are an integral part of the air handling systems that bring or draw fresh air into buildings.
Balancing Weights
Balancing weights are used to help balance rotating components or machinery.
Pressure Blowers and Fans
Pressure blowers and fans are used to create and sustain a positive pressure for inflatable structures, clean rooms, laboratories, and medical facilities. Pressurization blowers are fans that create a positive pressure in a sealed or restricted environment.
Air Compressors
Air compressors are machines that compress air to higher than atmospheric pressures for delivery to pneumatic or robotic tools, industrial equipment, or direct-use applications.
Air Scrubbers, Wet Scrubbers, and Gas Scrubbers
Air scrubbers, wet scrubbers, and gas scrubbers are air pollution control devices that use a high-energy liquid spray to remove aerosol and gaseous pollutants from an air stream. The gases are removed either by absorption or chemical reaction.

Topics of Interest

14-1 General With the exception of the fact that gases are compressible the theory of design for equipment to move gases and vapors is similar to that of pumps for liquids. Heads developed in terms...


Fans, Centrifugal Besides being used in process plants, centrifugal fans are common in building heating and air-conditioning systems. Vendors for these systems should be consulted for required...

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Symbols ? p = vapor pressure differential, in. Hg (kPa) ? T = temperature difference, F ( C) ? = efficiency, % v = specific volume, ft 3/lb (m 3/kg) ? = density, lb/ft 3 (kg/m 3) A = area, in. 2...

Era Period Epoch Millions of years ago Cenozoic Quaternary [*] Holocene 0.01 Pleistocene 0.01 1.8 Tertiary [*] Pliocene 1.8 5.1 Miocene 5.1 24.6 Oligocene 24.6 38.0 Eocene 38.0 54.9...