Time synchronization, user administration

General principle

Process data are only evaluable, if all components of a process control system are using the same time of day. Because that, all subsystems like OS and AS should run with time synchronization. The synchronization is basing on a master / slave architecture. Two general synchronization modes can be distinguished:

The NTP mode is suitable for PC Stations without own time synchronization functionality. By the NTP mode, network components fetch the time from an external NTP server. SICLOCK TC 400 is recommended as NTP server in PCS 7 plants.

The SIMATIC mode uses an internal time synchronization functionality provided by WinCC Software on OS Server Stations. Those OS Servers are able to work as cooperative time masters.

PLC Clock Setting in OS Computer properties Operating with Local Standard Time and Coordinated Universal Time (UTC)

In PCS 7, UTC is used internally as a rule within the system. Time information displayed to the operator in process mode can be converted from UTC to the respective local time. This makes it possible to configure a system, for example, with the automation system in a different time zone than the operator station. If necessary, the plant operator can also switch back and forth between coordinated universal time display and local time display in runtime. See the OS Computer properties below with its preferred settings:

Time Synchronization Settings in the WinCC Explorer

Time synchronization via the plant bus requires one of the following settings in the WinCC project of the OS Server / Single station. These settings have to be done in the Editor ―Time Synchronization‖ of the WinCC Explorer.

Settings in the HW configuration of the AS & Settings in the AS-CP for the plant bus

The time message frames of the time master are forwarded to the automation systems on the plant bus. The AS Communication Processor for Industrial Ethernet requires settings:

life beat Monitoring

The life beat monitoring function is used to monitor the functionality of all AS and OS of the process control system. A process control message is generated if an AS or OS do not respond to a life beat request.

Life beat monitoring is performed centrally from an OS that you have designated as the lifebeat monitor. The lifebeat monitor monitors all OS servers, OS clients, and automation systems. You configure lifebeat monitoring in the "Lifebeat Monitoring" editor of the WinCC explorer. 

Requirements

The hardware configuration and network connections for all automation systems and operator stations have been configured in SIMATIC Manager. An OPC connection is created in WinCC Explorer for each operator station that you wish to monitor.

What you see in the OS Runtime

No problem: If there is no problem on the level of communication between the OS and the system being monitored, the Plant Network Configuration picture displays the icon of the AS as shown below:

User administration

Basic User Authorization Concept

User rights are administered in the "User Administrator" Editor of WinCC Explorer.

Example: For an operator it is possible to operate valves Manual/Auto and Close/Open, but changing the Monitoring Time is not possible (field is grayed out).

Function: It is because this operator is not authorized for the related function.

Setting User Administrator

You manage and supervise user access rights in the User Administrator. The main task of the User Administrator in runtime is to monitor system login and access rights. In the editor "user administrator" two possibilities are available for managing user rights: WinCC Logon: creation of user groups/users and authorization assignment SIMATIC Logon: activate check box "SIMATIC Logon"; creation of user groups and authorization assignment The different OS areas and the plant structure from the SIMATIC Manager are shown in the User Administrator. Some of the authorizations can be assigned area specific.

As of PCS 7 V8.0, 2 new operation levels are pre-defined in the User Administrator being freely configurable:

Extended operation 1

Extended operation 2

Instance-specific parameterization

There is a new input field "Operation Level" (new attribute "Op_Level") at every relevant 

Operator-controllable input.

The numbers 1 to 5 are permitted inputs. They are assigned as follows:

1 = OperationLevel1_backup = Process Controlling (Preset in the block icon)

(Corresponds to WinCC User Administrator „Level 5―)

2 = OperationLevel2_backup = Higher process Controlling (Preset in the block icon)

(WinCC „Level 6―)

3 = OperationLevel3_backup = Highest process Controlling (Preset in the block icon)

(WinCC Level 1100―)

4 = OperationLevel4_backup = New: Extended operation 1 (WinCC „Level 1101―)

5 = OperationLevel5_backup = New: Extended operation 2 (WinCC „Level 1102―)

This permits instance-specific configuration that supports a detailed definition which functions are available for a specific user (group).

Introduction to OS project editors