8 Further Notes on Operation
B
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40
CP 443-1 for Industrial Ethernet / Manual Part B
Release 07/2010
C79000-G8976-C223
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06
Notice
Note the following regarding time-of-day synchronization in NTP mode:
If the CP recognizes an NTP frame as being “not exact” (example: NTP server is
not externally synchronized), it is not forwarded to the communication bus. If this
problem occurs, none of the NTP servers is displayed as “NTP master” in the
diagnostics; rather all NTP servers are displayed only as being accessible.
Forwarding the time-of-day message
You can configure the direction in which time-of-day messages are forwarded in
STEP 7 / NCM S7 in the properties dialog of the CP as follows.
S
Configuration “from station to LAN”
The CP forwards time frames from the CPU to Industrial Ethernet when the
local CPU is time master (SIMATIC mode only) or when the time of day is
forwarded by a different CP on the K bus.
S
Configuration “from LAN to station”
The CP forwards time frames from the CPU to Industrial Ethernet when one of
the following components is time master:
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In the SIMATIC mode:
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a remote CPU 41x
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a SIMATIC NET time transmitter
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a CP 1430 TF
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an NTP server when using the NTP mode
As default, time-of-day synchronization is not activated for the CP and it does not
therefore forward the time. However, the internal clock of the CP is also
synchronized in this situation when a time-of-day frame is received from the
communication bus or from Industrial Ethernet.
Synchronization using one of the two modes described here must be configured in
STEP 7 in the properties dialog of the CP
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“Time-of-Day Synchronization” tab.
For more detailed information on the parameters and options, please refer to the
online help in the properties dialog.