ifm
Device manual AS-i M4 Gateway Profibus DPV1 (AC1375, AC1376)
2012-02-23
Glossary of Terms
516
applications. These minimum versions are
supplied with certain products to meet the
prerequisites for the execution of the actual
product or to be able to look at or use results
generated by this product on other processors:
making available all routines required to
execute a program in a programming
language, e.g. interactions with the
operating system, memory requirements,
error routines, inputs and outputs.
S
SD card
An SD memory card (short for
S
ecure
D
igital
Memory Card) is a digital storage medium that
operates to the principle of flash storage.
Self-test
Test program that actively tests components or
devices. The program is started by the user
and takes a certain time. The result is a test
protocol (log file) which shows what was tested
and if the result is positive or negative.
SELV
SELV =
S
afety
E
xtra
L
ow
V
oltage
Active parts of safety extra low voltage circuits
must neither be connected to ground nor to
protective wires of other circuits. They must be
safely separated from active parts with higher
voltage.
SELV circuit = secondary circuit (output
voltage) which is rated and protected so that
its voltages do not exceed a safe value in case
of correct operation (of the power supply) or in
case of a single fault (of the power supply).
SELV circuits are separated from the input
voltage (mains voltage) by double or enhanced
insulation. The voltage value must not exceed
60 V DC (or 42.4 V AC).
Single slave
Slave whose address number may only
occur once on the
master.
Slave
Passive participant on the bus, only replies on
request of the
master. Slaves have a clearly
defined and unique
address in the bus.
Slave configuration
The following terms need to be distinguished...
- AS-i projected configuration
(PCD
(
→
)),
- AS-i current configuration
(CDI
(
→
)),
- CTT projected configuration
(PCCD
(
→
page
)),
- CTT current configuration
(CCDI
(
→
page
)).
Symbols
Pictograms are figurative symbols which
convey information by a simplified graphic
representation.
Chapter What do the symbols and formats
mean? (
→
page
System variable
Variable to which access can be made via IEC
address or symbol name from the PLC.
T
Target
The target indicates the target system where
the PLC program is to run. The target contains
the files (drivers and if available specific help
files) required for programming and parameter
setting.
TCP
The
T
ransmission
C
ontrol
P
rotocol is part of
the TCP/IP protocol family. Each TCP/IP data
connection has a transmitter and a receiver.
This principle is a connection-oriented data
transmission. In the TCP/IP protocol family the
TCP as the connection-oriented protocol
assumes the task of data protection, data flow
control and takes measures in the event of
data loss. (compare:
UDP)
U
UDP
UDP (
U
ser
D
atagram
P
rotocol) is a minimal
connectionless network protocol which belongs
to the transport layer of the internet protocol
family. The task of UDP is to ensure that data
