Configuration
4.4 Time-of-day synchronization
CP 1243-7 LTE
Operating Instructions, 04/2017, C79000-G8976-C381-03
49
Dependence of the synchronization method on the use of the CP
Depending on the use of the telecontrol communication or the security functions, the
following synchronization methods can be selected:
●
Telecontrol communication disabled, security disabled
–
NTP
–
Time from the CPU
●
Telecontrol communication disabled, security enabled
–
NTP
–
NTP (secure)
–
Time from the CPU
●
Telecontrol communication and security enabled
–
Time from partner
–
NTP
–
NTP (secure)
–
Time from the CPU
Time-of-day synchronization with the S7-1200
When using an external time source, the S7-1200 station can obtain the current time of day
both via the CPU as well as via a CP.
With the S7-1200 there is no forwarding of the time of day from the station to the subnet.
Note
Recommendation: Time-of-day synchronization only by 1 module
Only have the time of day of the station from an external time source synchronized by a
single module so that a consistent time of day is maintained within the station.
When the CPU takes the time from the CP, disable time-of-day synchronization of the CPU.
Time-of-day synchronization of the CPU
The following synchronization methods are possible for the CPU:
●
NTP
Only this option can be configured actively for the CPU:
●
Time from CP
The CPU adopts the time of day from a CP of the station if time forwarding from the CP to
the CPU is enabled (see below).
