Automating Manufacturing Systems - Process Control and ...

plc glossary - 35.28
added at a slow rate until the reagent detects a change.
toggle switch - a switch with a large lever used for easy reviews of switch settings, and easy grasping.
token - an indicator of control. Often when a process receives a token it can operate, when it is done it gives
it up.
TOP (Technical Office Protocol) - a network protocol designed for offices. It was promoted in conjunction
with MAP in the 1980s, but never became widely used.
top-down design - a design is done by first laying out the most abstract functions, and then filling in more of
the details as they are required.
topology - 1. The layout of a network. 2. a mathematical topic describing the connection of geometric
entities. This is used for B-Rep models.
torque - a moment or twisting action about an axis.
torus - a donut shape
toroidal core - a torus shaped magnetic core to increase magnetic conductivity.
TPDDI (Twisted Pair Distributed Data Interface) - counter rotating token ring network connected with
twisted pair medium.
TQC (Total Quality Control) - a philosophical approach to developing quality methods that reach all levels
and aspects of a company.
transceiver (transmitter receiver) - a device to electrically interface between the computer network card, and
the physical network medium. Packet collision hardware is present in these devices.
transducer - a device that will convert energy from one form to another at proportional levels.
transformations - include translation, rotation, and scaling of objects mathematically using matrix algebra.
Transformations are used to move objects around in a scene.
transformer - two separate coils wound about a common magnetic coil. Used for changing voltage, current
and resistance levels.
transient - a system response that occurs because of a change. These effects dissipate quickly and we are left
with a steady state response.
transmission path - a system component that is used for transmitting energy.
transport layer - an OSI network model layer.
TRIAC (TRIode Alternating Current) - a semiconductor switch suited to AC power.
true - a logic positive, high, or 1.
truth table - an exhaustive list of all possible logical input states, and the logical results.
TTL (Transistor Transistor Logic) - a high speed for of transistor logic.
TTY - a teletype terminal.
turbine - a device that generates a rotational motion using gas or fluid pressure on fan blades or vanes.
turbulent flow - fluids moving past an object, or changing direction will start to flow unevenly. This will
occur when the Reynold’s number exceeds 4000.
twisted pair - a sheme where wires are twisted to reduce the effects of EMI so that they may be used at
higher frequencies. This is cassualy used to refer to 10b2 ethernet.
TXD (Transmitted Data) - an output line for serial data transmission. It will be connected to an RXD input
on a receiving station.
35.21 U
UART (Universal Asynchronous Receiver/Transmitter) -
UDP (User Datagram Protocol) - a connectionless method for transmitting packets to other hosts on the
network. It is seen as a counterpart to TCP.
ultrasonic - sound or vibration at a frequency above that of the ear (> 16KHz typ.)
ultraviolet - light with a frequency above the visible spectrum.
UNIX - a very powerful operating system used on most high end and mid-range computers. The predecessor
was Multics. This operating system was developed at AT & T, and grew up in the academic
environment. As a result a wealth of public domain software has been developed, and the