353
ifm
Device Manual SmartSPS AC14 with EtherNet/IP interface (AC1421, AC1422), Firmware 3.1.2
2015-11-30
Glossary of Terms
Due to the absence of moving parts, flash
is noiseless and insensitive to shocks and
magnetic fields.
Disadvantages of flash memories
A storage cell can tolerate a limited
number of write and delete processes:
• Multi-level cells: typ. 10 000 cycles
• Single level cells: typ. 100 000 cycles
Given that a write process writes memory
blocks of between 16 and 128 Kbytes at
the same time, memory cells which require
no change are used as well.
>
FMEA
FMEA =
F
ailure
M
ode and
E
ffects
A
nalysis.
Method of reliability engineering, to find
potential weak points. Within the framework of
quality or security management, the FMEA is
used preventively to prevent faults and
increase the technical reliability.
>
FRAM
FRAM, or also FeRAM, means
Fe
rroelectric
R
andom
A
ccess
M
emory. The storage
operation and erasing operation is carried out
by a polarisation change in a ferroelectric
layer.
Advantages of FRAM as compared to
conventional read-only memories:
• non-volatile,
• compatible with common EEPROMs, but:
• access time approx. 100 ns,
• nearly unlimited access cycles possible.
>
G
Gateway
Gateway = access, coupler.
Gateways enable connection of completely
different systems. Gateways are used when
two incompatible network types are to be
connected by converting the protocol of one
system to the protocol of the other system.
Example: connection between AS-i and
higher-level fieldbus systems such as
Ethernet DP,
DeviceNet, Interbus-S or
other interfaces, e.g. RS-485. The device
includes an AS-i master which is directly
coupled to the
host interface (e.g. Ethernet
DP slave).
>
Gateway transfer time
The time that is needed for the input data in
the DP-RAM of the AS-i master to be copied
into the output data of the netX, and vice
versa. The distance from DP-RAM to DP-RAM
is decisive.
>
>
GSD
G
eneric
S
tation
D
escription
Describes the interface to the device to be
connected to the fieldbus.
You can find the current version of the GSD
file on the
ifm
homepage:
→
[Service] > [Download] > [Industrial
communication]
e.g. for AC1375:
GSD file for SmartLink AC1375
download the file
ifm
...
07E5.gsd
(... =
version)
>
GSDML
GSDML =
G
eneric
S
tation
D
escription
M
arkup
L
anguage.
Description language which can describe the
characteristics of a device family across
several levels. In this XML scheme, as much
as possible of the semantics of the
GSD was
adopted.
>
H
HMI
HMI =
H
uman
M
achine
I
nterface
>
Host
The controller in the hierarchy above the AS-i
master, e.g. a PLC or a processor.
>