Siemens SIMATIC PCS 7 Parts list manual

SIMATIC
Process Control System PCS 7
Time synchronization (V8.0)
Function Manual
03/2012
A5E02779849-02
Preface
1
Fundamentals
2
Configurations for time
synchronization of a PCS 7
plant
3
Planning time
synchronization
4
Configuring time
synchronization
5
Checking time
synchronization
6

Legal information
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A5E02779849-02
Ⓟ 05/2012 Technical data subject to change
Copyright © Siemens AG 2012.
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Table of contents
1 Preface.........................................................................................................................................................7
2Fundamentals ............................................................................................................................................11
2.1 Using time synchronization in PCS 7..........................................................................................11
2.2 Time synchronization options for PCS 7 components.................................................................13
2.3 Time displayed in PCS 7.............................................................................................................13
2.4 Time synchronization in distributed PCS 7 plants.......................................................................14
2.5 Central plant clock.......................................................................................................................17
2.6 Time levels for a PCS 7 plant (stratum).......................................................................................17
2.7 Time synchronization in PCS 7 - mode of operation...................................................................20
2.7.1 Time master and time slave........................................................................................................20
2.7.2 Time sources for a PCS 7 plant...................................................................................................22
2.7.3 Example of the time synchronization sequence..........................................................................23
2.8 Network environment of a PCS 7 plant.......................................................................................24
2.8.1 Overview......................................................................................................................................24
2.8.2 Legend for figures used in this documentation............................................................................25
2.8.3 Network environment within a domain.........................................................................................25
2.8.4 Network environment within a work group...................................................................................26
2.8.5 Network environment in redundant, high-availability networks....................................................27
2.8.6 Network environment on separate networks with one central plant clock...................................28
3 Configurations for time synchronization of a PCS 7 plant..........................................................................31
3.1 Overview of recommended configurations..................................................................................31
3.2 Rules for time synchronization in PCS 7.....................................................................................32
3.3 Configurations for time synchronization in a work group.............................................................33
3.3.1 Configuration of time synchronization with central time master in a work group.........................33
3.3.2 Configuration of time synchronization without central time master in a work group....................35
3.4 Configuration for time synchronization in a Windows domain.....................................................36
3.4.1 Configuration of time synchronization with central time master in a Windows domain with a
hierarchy......................................................................................................................................36
3.4.2 Configuration of time synchronization with central time master in a Windows domain with a
hierarchy......................................................................................................................................39
3.4.3 Configuration of the time synchronization in a Windows domain with multiple hierarchies.........40
4 Planning time synchronization....................................................................................................................43
4.1 Selecting the time master............................................................................................................43
4.2 Selecting the central plant clock..................................................................................................43
5 Configuring time synchronization ...............................................................................................................47
5.1 Introduction..................................................................................................................................47
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Function Manual, 03/2012, A5E02779849-02 3

5.2 Setting the time displayed...........................................................................................................48
5.2.1 How to configure the operator station display.............................................................................48
5.2.2 How to convert the local time zone and daylight saving time parameters...................................50
5.3 Overview of configuration steps, depending on the configuration...............................................52
5.3.1 Configuration steps for time synchronization with central time master in a work group..............52
5.3.2 Configuration steps for time synchronization without a central time master in a work group......53
5.3.3 Configuration steps for time synchronization with a central time master in a Windows domain with
a hierarchy...................................................................................................................................54
5.3.4 Configuration steps for time synchronization without a central time master in a Windows domain
with a hierarchy...........................................................................................................................55
5.4 Commissioning a central plant clock...........................................................................................56
5.4.1 Commissioning the SICLOCK TC 400........................................................................................56
5.4.2 Commissioning the SICLOCK TM/TS.........................................................................................59
5.4.3 Commissioning GPS receivers....................................................................................................62
5.4.4 Commissioning the DCF 77 receiver...........................................................................................64
5.5 Configuring the time synchronization of the OS .........................................................................66
5.5.1 Overview of configuration steps..................................................................................................66
5.5.2 How to set time synchronization on an OS in a work group with central time master.................67
5.5.3 How to set time synchronization on an OS in a work group without central master.".................70
5.5.4 How to set time synchronization on an OS in a domain with central time master.......................73
5.5.5 How to set time synchronization on an OS in a domain without central time master..................78
5.5.6 How to set the OS server for reception of time service via DCF77RS........................................82
5.6 Configuring time synchronization for a PC station without OS ...................................................84
5.6.1 Overview of configuration steps..................................................................................................84
5.6.1.1 How to make DCF 77 Client Service settings on a PC station without OS.................................84
5.6.1.2 How to synchronize PC stations using NTP mode......................................................................86
5.6.2 Time-of-day synchronization for PC stations...............................................................................87
5.6.2.1 How to set time synchronization on an engineering station........................................................87
5.6.2.2 How to set time synchronization on a BATCH/operator station...................................................87
5.6.2.3 How to set time synchronization on a route control/operator station...........................................88
5.6.2.4 How to set time synchronization at the Process Historian and at the Information Server...........88
5.7 Time synchronization via conventional point-to-point connections..............................................88
5.7.1 Configuring directly connected time receivers.............................................................................88
5.8 Configuring time synchronization on an AS.................................................................................92
5.8.1 How to set time synchronization on an AS for SIMATIC mode...................................................92
5.8.2 How to set time synchronization on an AS for NTP mode...........................................................98
5.9 Configuring time synchronization for the SIMATIC PCS 7 BOX and SIMATIC PCS 7 AS RTX 101
5.9.1 Overview of time synchronization for the SIMATIC PCS 7 BOX and SIMATIC PCS 7 AS RTX101
5.9.2 How to set the time synchronization source..............................................................................102
5.9.3 How to set the OS properties....................................................................................................103
5.9.4 How to configure the time synchronization for the AS...............................................................104
5.9.5 How to set OS time synchronization..........................................................................................105
5.10 Configuring time synchronization with multiple networks..........................................................106
5.10.1 Configuring time synchronization for separate networks using a central clock.........................106
5.10.2 How to configure SCALANCE X414-3E for the separation of time signals...............................108
5.10.3 How to configure an OSM/ESM for separating time signals......................................................109
5.11 Configuring redundant PCS 7 systems.....................................................................................110
Table of contents
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4Function Manual, 03/2012, A5E02779849-02

5.11.1 How to configure time synchronization of OS servers with a redundant communication module
and external clock......................................................................................................................110
5.11.2 How to configure time synchronization on a PCS 7 system with redundant bus system..........111
5.12 Configuring time synchronization of the domain controller (DC) ..............................................112
5.12.1 How to configure time synchronization of the domain controller...............................................112
6 Checking time synchronization.................................................................................................................115
6.1 How to check the time of the PC stations..................................................................................115
6.2 How to configure the status check of the time master role of the OS server ............................116
Glossary....................................................................................................................................................119
Index.........................................................................................................................................................121
Table of contents
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 5

Preface 1
Purpose of this documentation
The
time synchronization documentation provides support for the configuration and
commissioning of the "time synchronization" function in a PCS 7 plant.
The documentation provides information about the following topics:
● Time synchronization in a PCS 7 plant
● Planning time synchronization in a PCS 7 plant
● Configuring time synchronization for a PCS 7 plant
Note
You will find information on high-precision time stamping in the function manual PCS 7
Process Control System; High-precision time stamping .
Organization
The documentation is organized according to the following topics:
● Fundamentals of time synchronization mode of operation in a PCS 7 plant
● Configuration possibilities of PCS 7 with time synchronization
● Planning a PCS 7 plant with time synchronization
● Configuring the time synchronization for different plant configurations
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 7

Target group and benefit
This documentation is intended for personnel working in the fields of sales, planning, and
configuration:
Target group Using the documentation Target-group relevant chapters of the
documentation
Sales Sales personnel give clear advice to their
customers on implementing the "time
synchronization" function in a PCS 7 plant.
● "Fundamentals"
● "Configurations for time
synchronization of a PCS 7 plant"
● "Planning time synchronization"
Planning The system planner uses the information
in the documentation for optimal set up
and the components necessary in this
regard for planning a PCS 7 plant with the
"time synchronization function".
● "Fundamentals"
● "Configurations for time
synchronization of a PCS 7 plant"
● "Planning time synchronization"
Configuration The configuration engineer is provided
with exact instructions relative to the "time
synchronization" function; these
instructions show the specific steps that
are necessary to adjust the time
synchronization at all relevant points.
● "Configuring time synchronization"
Options for accessing PCS 7 documentation
Note
PCS 7 Readme
The information given in the PCS 7 Readme on the Internet takes precedence over all the
PCS 7 manuals. Please read this PCS 7 Readme carefully; it contains important information
and amendments on PCS 7.
● The PCS 7 Readme on the Process Control System; SIMATIC PCS 7 DVD contains
important information regarding PCS 7 and takes precedence over the PCS 7
documentation supplied.
● After installation of PCS 7, you can find documents such as Process Control System PCS
7; PCS 7 Readme and What's New in PCS 7? via the submenu SIMATIC > Product
Information > <Language>.
As of PCS 7 V8.0, you receive basic PCS 7 system documentation with the Process Control
System; SIMATIC PCS 7 DVD.
The PCS 7 Internet site www.siemens.de/pcs7-dokumentation (www.siemens.com/pcs7-
documentation) provides convenient access to the complete PCS 7 documentation. You can
find the following for the latest PCS 7 versions:
Preface
Time synchronization (V8.0)
8Function Manual, 03/2012, A5E02779849-02

●In the section "Hardware manuals for SIMATIC PCS 7 ..."
– The manuals for components approved for a PCS 7 version
●In the section "Software manuals for SIMATIC PCS 7 ..."
– The complete system documentation
– The separate setup program for PCS 7 documentation and the PCS 7 help system for
download. After the installation of the setup program, you will find the documentation at
the following locations on the Engineering Station:
- As online help (CHM file) for the SIMATIC Manager application
- As a PDF file in the Windows Start menu with the SIMATIC documentation
– The complete documentation for PCS 7 as a Manual Collection
Skills required
Only qualified personnel should commission and operate the PCS 7 products.
Skills in the following areas are prerequisite:
● STEP 7
● PCS 7
● "Automation technology"
● Basic WinCC skills
● For plants with domain structure: Knowledge of the Windows administration
Validity of the documentation
This documentation is valid for the
Process Control System; SIMATIC PCS 7 DVD software
package as of V8.0.
Changes compared to the previous version
Below, you will find an overview of the most important changes in the documentation compared
to the previous version.
New as of PCS 7 V8.0
● Synchronization for PC stations
For additional information, refer to the section "How to make DCF 77 Client Service settings
on a PC station without OS (Page 84)."
Preface
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 9

Fundamentals 2
2.1 Using time synchronization in PCS 7
Introduction
Plants in which Process Control Systems are used contain numerous components that
exchange data. Most plants require time synchronization for controlling processes and
information. There are additional requirements in terms of the documentation of event
sequences.
If the timing of components in the overall system is not synchronized, these tasks can only
be supported by the internal clock of the individual components.
Components that are equipped with an internal hardware clock (RTC = Real Time Clock)
include:
● Domain servers
● Servers
● Clients
● PC stations
● Automation systems
● I/O
● Sensors
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Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 11

Time synchronization
Time synchronization means that one system component (time master) provides a precise
time for all the other components (time slaves). The time information (date and time) can either
be distributed by the time master, or be requested by the time slaves. For the overall task, all
components within the system must evaluate this time information.
Time synchronization applications
The list below contains various examples of aspects requiring time synchronization of all
components within the process automation:
● Synchronizing processes
● Controlling complex sequences
● Logging and documenting sequences
● Validating processes
● Analyzing processes
● Analyzing the causes and effects of events
PCS 7 functions
The following list contains some of the key PCS 7 functions for which time synchronization is
absolutely necessary:
● Interpretation of causal relationships
● Message processing in correct sequence
● Time stamp
● Time-of-day interrupts
● Runtime meter
● Redundancy compare
● Batch monitoring
● Authentication of a domain client
Fundamentals
2.1 Using time synchronization in PCS 7
Time synchronization (V8.0)
12 Function Manual, 03/2012, A5E02779849-02

2.2 Time synchronization options for PCS 7 components
Time synchronization for PCS 7 components
The table below shows the PCS 7 components for which time synchronization is possible:
Station Time synchronization For further information, refer to the section ...
Operator station ● Via the terminal bus
● Via the plant bus
● "How to set time synchronization on an OS in a domain with
central time master. (Page 73)"
● "How to set time synchronization on an OS in a work group
with central time master (Page 67)"
BATCH station ● Via the operating system ● "How to make DCF 77 Client Service settings on a PC station
without OS (Page 84)"
● "How to set time synchronization on a BATCH/operator
station. (Page 87)"
Route Control
Station
● Via the operating system ● "How to make DCF 77 Client Service settings on a PC station
without OS (Page 84)"
● "How to set time synchronization on a route control/operator
station. (Page 88)"
SIMATIC PCS 7
BOX
● At integration in a
PCS 7 plant
● "Configuring time synchronization for the SIMATIC PCS 7
BOX and SIMATIC PCS 7 AS RTX (Page 101)"
AS ● Via the plant bus ● "How to set AS time synchronization (Page 92)"
Domain controller ● With a domain controller as time
master on the terminal bus
● "How to set time synchronization in a Windows domain with
a central time master (Page 36)"
● "How to set time synchronization in a Windows domain without
a central time master (Page 39)"
V5-compatible mode
Note
Contact Customer Support if you want to use time synchronization in V5-compatible mode.
2.3 Time displayed in PCS 7
Coordinated Universal Time (UTC)
Coordinated Universal Time (UTC) is an international time basis that takes as its precedent
the precision of atomic clocks. UTC refers to the Greenwich prime meridian in London.
UTC does not take daylight saving time into account.
Fundamentals
2.3 Time displayed in PCS 7
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 13

Local time
East of the prime meridian, one or more hours is added to the universal time measured in
Greenwich, depending on the distance in question. West of the prime meridian, the hours are
subtracted.
The following table shows some examples of time zones and their time differences in relation
to UTC:
Location Time zone Zone time Time
Greenwich 0. Longitude UTC = Coordinated Universal Time UTC 12:00
Berlin 15. Eastern longitude CET = Central European Time UTC + 1h: 13:00
Moscow 45. Eastern longitude MSK = Moscow Time UTC + 3h: 15:00
Tokyo 120. Eastern longitude JST = Japan/Korea Standard Time UTC + 9h: 21:00
Buenos Aires 45. Western longitude No designation UTC – 3h: 9:00
Daylight saving time/standard time
A number of countries have introduced conversion of standard time (local time) to daylight
saving time for the summer months.
Example:
In central Europe, standard time differs by plus one hour, while daylight saving time differs by
plus two hours in relation to standardized universal time (UTC).
UTC CET standard time CEST daylight saving time
12:00 UTC + 1h = 13:00 UTC + 2h = 14:00
Time display in process mode
In PCS 7, the operator can toggle the time displayed on the operator station between UTC
and local time while the plant is in process mode. The operator station can display the local
time, including daylight saving time and standard time.
Note
If time-dependent data of different time zones is displayed or processed on a PCS 7
component, then use UTC for display on the operator station as well.
2.4 Time synchronization in distributed PCS 7 plants
Introduction
PCS 7 supports system configurations where subcomponents are installed at different
locations, or even in different time zones. An example would be the installation of an automation
Fundamentals
2.4 Time synchronization in distributed PCS 7 plants
Time synchronization (V8.0)
14 Function Manual, 03/2012, A5E02779849-02

system and an operator station at different locations. The time must be synchronized for the
entire PCS 7 plant in order to optimize the sequence of all the processes.
In PCS 7, the times of subcomponents are directly synchronized within a time zone. PCS 7
uses the "time synchronization" function to synchronize different time zones.
Time response in distributed PCS 7 plants
The following figure shows that time jumps may occur in process control systems (for example,
in the alarm lists) if there is no time synchronization. The processes do not run synchronously:
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If the times for the components of a distributed PCS 7 plant are synchronized, all of the
processes will run in correct chronological order and will be archived correctly.
Fundamentals
2.4 Time synchronization in distributed PCS 7 plants
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 15

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Rules for configuring distributed PCS 7 plants
Since PCS 7 plants generally operate on the basis of UTC internally, their specific components
can be distributed on a global scale. In order to safeguard the interplay of components - even
across different time zones - please observe the following:
● Use UTC as the common time base in all PCS 7 plants. All plant components running with
UTC will display the same time after time synchronization.
● Set up a PC station as a PCS 7 Web server in all PCS 7 plants, using the PCS 7 OS web
option. This will allow you to access the PCS 7 Web servers of the PCS 7 plants via multiple
Web clients (in PCS 7: WebNavigator client or WebNavigator diagnostic client) at the
company's headquarters. You can convert the time display on the Web client to the local
system time. Please note the resulting time difference.
● If monitoring a PCS 7 plant in a different time zone on an OS, you can convert the time
displayed from UTC to the local system time using the OS control panel. Please note the
resulting time difference.
Note the following to prevent external synchronization:
NOTICE
Time message frames from external networks
Time message frames from external networks must be prevented from infiltrating process
control systems that are distributed across several networks or connected to the Intranet
or Internet.
Always connect the company network and the plants using network components that
enable separation of time signals, e.g. a router. Configure those network components so
that forwarding of time message frames is blocked.
Fundamentals
2.4 Time synchronization in distributed PCS 7 plants
Time synchronization (V8.0)
16 Function Manual, 03/2012, A5E02779849-02

Further information
● Section "Setting the time displayed (Page 48)"
● WinCC online help
2.5 Central plant clock
Using a central plant clock
You should always synchronize all Process Control Systems using either a precise time or a
standard time. In the case of PCS 7 plants, we recommend performing synchronization by
means of a central plant clock. The central plant clock manages the time centrally for the entire
plant and synchronizes all of the other plant components via their interfaces.
Recommendation:
Using the SICLOCK TC 400 as the central plant clock. The SICLOCK should be synchronized
with a standard time, e.g. using GPS or DCF 77, as this ensures that a correct reference to
the actual time is constantly available.
Standard time
The following standard times are typical for PCS 7 plants:
● GPS
The GPS signal is provided by a global satellite system.
● DCF 77
The DCF 77 signal is available in Germany and in certain parts of Europe using
corresponding radio signal receivers.
2.6 Time levels for a PCS 7 plant (stratum)
Introduction
Time synchronization of a system involves one component synchronizing the next component
by forwarding a time message frame. Forwarding time message frames will result in time
delays. You should make allowances for this fact when setting up a PCS 7 plant.
The following figure shows an example of the structure of a PCS 7 plant with several domains:
Fundamentals
2.6 Time levels for a PCS 7 plant (stratum)
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 17

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Definition stratum
A PCS 7 plant component such as the central time clock (SICLOCK) receives the definitive
time from an external time source (e.g. a GPS signal) and forwards it to other components to
be synchronized. As a result, the SICLOCK is the time master for those components whose
time is determined in relation to the SICLOCK time. Components which are capable of
providing a time are considered time masters if other components use their time information.
All time masters form a hierarchy that consists of higher-level and lower-level time masters.
Relative position within this hierarchy is designated with a number; the "stratum". Multiple time
masters may be located within a single stratum. These time masters use the time message
frame at the same point in time to synchronize their own clock.
The stratum indicates the following:
● The number of time levels between the stratum in which the time master is located and the
stratum in which the time source (e.g. the GPS satellite) is located
● The time level where the components in a network are located
Fundamentals
2.6 Time levels for a PCS 7 plant (stratum)
Time synchronization (V8.0)
18 Function Manual, 03/2012, A5E02779849-02

Time synchronization using strata
The following figure shows an example of time synchronization using strata:
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The above example shows time synchronization with the following structure:
● Stratum 0
The time source is an atomic clock. This atomic clock synchronizes the GPS satellites or
the DCF 77 senders, for example.
● Stratum 1
The central plant clock (SICLOCK) receives the time via a radio signal (e.g. GPS decoder
or DCF 77 receiver). SICLOCK transfers the time to domain controller 1 in stratum 2.
● Stratum 2
Domain controller 1 is the time slave of the central plant clock. Domain controller 1 transfers
the time to several domain controllers in stratum 3. Domain controller 1 is the time master
of the domain controllers in stratum 3.
● Stratum 3
The domain controllers in stratum 3 synchronize the time of their own process units in
stratum 4. The domain controllers in stratum 3 are the time masters of their own process
units.
● Stratum 4
The process unit components are time slaves.
Meaning of the strata for a PCS 7 plant
The higher the stratum level, the higher the potential time difference in relation to the original
time signal source. As time forwarding in a network also takes time, the time of lower strata
time masters is more precise than the time of higher strata time masters.
Fundamentals
2.6 Time levels for a PCS 7 plant (stratum)
Time synchronization (V8.0)
Function Manual, 03/2012, A5E02779849-02 19

Rules for planning a PCS 7 plant taking strata into account
Please observe the following rules when planning time synchronization, to ensure that the time
deviation of the time master is not too high in relation to the components in the lowest stratum:
● Use as few strata as possible.
● In most cases using a maximum of four strata is recommended.
● Use the same strata for the same structure elements.
When planning a PCS 7 plant to be synchronized, you should define exactly which hierarchy
would be best for receiving and forwarding the time.
2.7 Time synchronization in PCS 7 - mode of operation
2.7.1 Time master and time slave
Introduction
To ensure that all Process Control System components operate with as precise a time as
possible, one system component must be the time source for all other components. The precise
time must be permanently available and be used for synchronization on a cyclical basis
(synchronization interval).
Time master
The component that provides the precise time within a bus system is referred to as the time
master. Only one component within a stratum can be the active time master.
Time slave
The time slaves within a bus system are components which receive or fetch their time from a
time master.
Cooperative time master
On OS servers, in the WinCC Editor "Time Synchronization" permanently defined computers
are set for the time synchronization.
The OS server works as a cooperative time master, i.e. the first active OS server on the plant
bus which does not receive time message frames on the plant bus automatically switches to
time "Master" mode. All other OS servers on the plant bus detect the time message frame from
the time master and automatically switch to time "slave" mode.
Fundamentals
2.7 Time synchronization in PCS 7 - mode of operation
Time synchronization (V8.0)
20 Function Manual, 03/2012, A5E02779849-02