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Glossary
SITRANS SL
212
Operating Instructions, 12/2010, A5E01132948-04
PC card
Trademark of the Personal Computer Memory Card International Association (PCMCIA).
Designation for auxiliary cards that conform with PCMCIA specifications. A PC card that has
roughly the size of a credit card can be plugged into a PCMCIA slot. Version 1 specifies
cards of Type I with a thickness of 3.3 millimeters, which are designed mainly for use as
external memory. Version 2 of the PCMCIA specification also defines cards of Type II with a
thickness of 5 mm and cards of Type III with a thickness of 10.5 mm. Type II cards can
realize devices such as modems, fax cards and network interface cards. Type III cards are
equipped with devices that require more space, for example wireless communication
modules, or rotary storage media such as hard disk drives, for example.
PCMCIA
Association consisting of approx. 450 member companies of the computer industry whose
focus is set on providing worldwide standards for miniaturization and flexible use of PC
expansion cards in order to provide basic technologies to the market.
PROFIBUS
Process Field Bus-> International fieldbus standard to EN 50170/IEC 61158
PROFIBUS DP
PROFIBUS-DP (distributed peripheral I/O) is used for controlling sensors and actuators
using a central controller in production engineering. It is also used in connection with
"distributed intelligence", i.e. connecting multiple controllers to form a network. It provides
data transmission up to 12 Mbps on twisted-pair cables and data transmission over sliding
contacts for mobile subscribers in exceptional cases or optical data transmission in
unobstructed space.
PROFIBUS/MPI
Process Field Bus (standard bus system for process applications)
RS 232
A recognized industrial standard for serial data transmission, and applies to cable lengths up
to 15 m. Differential evaluation is not possible with RS 232. The sending and receiving of
data take place on different lines.
RS 485
RS 485 is an interface standard for line-based, differential, serial data transmission. RS 485
uses a pair of cables in order to transmit one inverted version and one non-inverted version
of the data signal. The original data signal is reconstructed at the receiver from the difference
between these two signals. It is then possible to use significantly longer transmission links
and higher speeds than with RS 232. Furthermore, several transmitters and several
receivers can be connected to one pair of conductors.