Automating Manufacturing Systems - Process Control and ...

plc glossary - 35.18
pneumatic systems. 2. a description for a geometry that does not have any infinitely small points
or lines of contact or separation. Most solid modelers deal only with manifold geometry.
MAP (Manufacturers Automation Protocol) - a network type designed for the factory floor that was widely
promoted in the 1980s, but was never widely implemented due to high costs and complexity.
mask - one binary word (or byte, etc) is used to block out, or add in digits to another binary number.
mass flow rate - instead of measuring flow in terms of volume per unit of time we use mass per unit time.
mass spectrometer - an instrument that identifies materials and relative proportions at the atomic level. This
is done by observing their deflection as passed through a magnetic field.
master/slave - a control scheme where one computer will control one or more slaves. This scheme is used in
interfaces such as GPIB, but is increasingly being replaced with peer-to-peer and client/server
networks.
mathematical models - of an object or system predict the performance variable values based upon certain
input conditions. Mathematical models are used during analysis and optimization procedures.
matrix - an array of numbers
MB MByte, KB, KByte - a unit of memory commonly used for computers. 1 KiloByte = 1 KByte = 1 KB =
1024 bytes. 1 MegaByte = 1 MByte = 1MB = 1024*1024 bytes.
MCR (Master Control Relay) - a relay that will shut down all power to a system.
memory - binary numbers are often stored in memory for fast recall by computers. Inexpensive memory can
be purchased in a wide variety of configurations, and is often directly connected to the CPU.
memory - memory stores binary (0,1) patterns that a computer can read or write as program or data. Various
types of memories can only be read, some memories lose their contents when power is off.
RAM (Random Access Memory) - can be written to and read from quickly.
It requires power to preserve the contents, and is often coupled with a
battery or capacitor when long term storage is required. Storage available
is over 1MByte
ROM (Read Only Memory) - Programs and data are permanently written
on this low cost ship. Storage available is over 1 MByte.
EPROM (ELECTRICALLY Programmable Read Only Memory) - A program
can be written to this memory using a special programmer, and
erased with ultraviolet light. Storage available over 1MByte. After a program
is written, it does not require power for storage. These chips have
small windows for ultraviolet light.
EEPROM/E2PROM (Electronically Erasable Programmable Read Only
Memory) - These chips can be erased and programmed while in use with
a computer, and store memory that is not sensitive to power. These can
be slower, more expensive and with lower capacity (measured in Kbytes)
than other memories. But, their permanent storage allows system configurations/data
to be stored indefinitely after a computer is turned off.
memory map - a listing of the addresses of different locations in a computer memory. Very useful when
programming.
menu - a multiple choice method of selecting program options.
message - a short sequence of data passed between processes.
microbar - a pressure unit (1 dyne per sq. cm)
microphone - an audio transducer (sensor) used for sound measurements.
microprocessor - the central control chip in a computer. This chip will execute program instructions to direct
the computer.
MILNET (MILitary NETwork) - began as part of ARPANET.
MMI (Man Machine Interface) - a user interface terminal.
mnemonic - a few characters that describe an operation. These allow a user to write programs in an intuitive
manner, and have them easily converted to CPU instructions.
MODEM (MOdulator/DEModulator) - a device for bidirectional serial communications over phone lines,
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