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Siemens IK PI · 2015
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Application
(continued)
PROFINET/Industrial Ethernet
Accessories
Time synchronization
As an alternative to receiving satellite signals, the DCF77 time
signal transmitter can be used as primary time source. The
transmitter is located near Frankfurt am Main and transmits long-
wave signals at a frequency of 77.5 kHz. Under normal condi-
tions, reception is possible up to a distance of about 1 500 km
from the transmitter.
The SICLOCK DCFRS wireless receiver with TTY output
(Article No. 2XV9450-1AR16) is used in this application.
Here too, a separate power supply is not required if a
SICLOCK TC100 or SICLOCK TC400 central plant clock is
used.
The advantages over satellite reception are lower costs and the
option of mounting the receiver inside a building. The last advan-
tage is especially useful if outdoor installation is not advisable,
e.g. due to vandalism.
Redundant modes
Due to the importance of having a reliable time supply in many
demanding applications, the SICLOCK system offers optional
redundant modes to further increase plant reliability. The redun-
dancy can be on the reception side, the network side, or even
be combined with a redundant central plant clock for highly sen-
sitive applications.
Reception-side redundancy
SICLOCK TC400 central plant clock with SICLOCK GPS1000 and SICLOCK DCFRS wireless receivers
In this application, SICLOCK GPS1000 and SICLOCK DCFRS
wireless receivers are used in parallel. External time information
can continue to be received even if one of the two primary time
sources fails. The SICLOCK TC100 and SICLOCK TC400 cen-
tral plant clocks each have two inputs for the wireless receivers.
Outdoor installation
Outdoor installation/
Indoor installation
up to 4 independent Ethernet networks
Twin wire
max. 1000 m
Twin wire
max. 1000 m
GPS satellite
DCF77
longwave time signal
Mainflingen near
Frankfurt/Main
SP01_00021
SICLOCK
GPS1000
SICLOCK
TC400
Industrial Ethernet
SICLOCK
DCFRS
ETH4
ETH1
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© Siemens AG 2014