86
Glossary
WAGO-I/O-SYSTEM 757
757-801 Bluetooth® Module RS-232
Manual
1.0.0
FE
(
F
unctional
E
arth)
FE is used for discharging electromagnetic faults. It is used only an EMC ground
connector and does not fulfill the protective earth (ground) (PE) function
according to VDE 0100.
FHSS
(
F
requency
H
opping
S
pread
S
pectrum)
General: The frequency hopping process known as “Frequency Hopping Spread
Spectrum” involves the division of a frequency range into sub-ranges, between
which the data transmission then alternates. This improves co-existence with other
networks and provides additional tapping protection and strength against narrow
band disturbing influences.
In the context of
Bluetooth
®
: Subdivision of the radio channel into 79 sub-
channels. The current subchannel is changed each time after transmission of a
packet. This may occur up to 1600 times per second.
H
Hardware Flow Control
Data flow control denotes different procedures for controlling data transmission
from terminal devices to a data network which do not operate synchronously in
such a manner as to provide a continuous data transmission flow as possible
without any losses.
Hardware procedures transfer control information via lines, which are also routed
to the data lines on the connectors. Hardware flow control is implemented using
corresponding signal levels on the associated interface lines.
HF
H
igh
F
requency
I
IEEE
I
nstitute of
E
lectrical and
E
lectronic
E
ngineers
IP Rating
(I
ngress
P
rotection acc. to IEC 60529)
Protection classes define, on the one hand, the measures for protection against
hazardous voltages (touch protection) and, on the other, protection measures
against moisture.
L
LED
(
L
ight-
E
mitting
D
iode)