How to Configure Operator Authorization Levels for SFC Auto and Manual Mode Switching in PCS 7

In SIMATIC PCS 7 V8.1, the AUTO and MANUAL mode switching buttons on SFC (Sequential Function Chart) faceplates appearing disabled for standard plant operators occur because Siemens elevated the default security authorization level for sequence mode transitions from Level 5 ('Process controlling') to Level 6 ('Higher process controlling'). To allow operators possessing Level 5 permissions to switch SFC operating modes, open WinCC Explorer, right-click the SFC editor, select Properties -> Open, navigate to the 'Authorization Levels' tab, and reassign the 'Operating mode / Auto-Manual' function to Authorization Level 5.

SFC Visualization Security Architecture in PCS 7

In SIMATIC PCS 7, procedural and state-based control sequences are engineered using Sequential Function Charts (SFC). When an operator interacts with SFCs in WinCC Runtime—via standard SFC faceplates, SFC controls, or overview picture windows—every interactive action is governed by the SIMATIC Logon user administration system.

WinCC evaluates access rights against pre-allocated authorization levels (Levels 1 through 16):
* Level 5 ('Process controlling'): Standard operational authority granted to control room operators, permitting routine setpoint modifications, valve opening/closing, and motor starting.
* Level 6 ('Higher process controlling'): Elevated authority typically reserved for shift supervisors, process specialists, or lead operators, permitting critical interlock overrides, batch aborts, and structural recipe interventions.

In modern PCS 7 versions (such as V8.0, V8.1, and V8.2), Siemens enhanced system security defaults by shifting critical state-machine transitions into higher authorization tiers.

Root Cause Analysis for Inactive Auto/Manual Buttons

Plant operators accustomed to legacy PCS 7 versions (such as PCS 7 V6.x and V7.x) frequently find that after an upgrade to PCS 7 V8.1, the AUTO and MANUAL buttons on SFC faceplates remain persistently greyed out and unclickable.

Why the Buttons Remain Disabled

Security Hardening Defaults: In legacy systems, switching an SFC between Automatic and Manual modes was assigned to Authorization Level 5. In PCS 7 V8.1, the default installation template binds this action to Authorization Level 6.
User Profile Restriction: Plant operators configured with standard Level 5 permissions satisfy regular process control checks, but WinCC rejects their access when attempting to toggle SFC operating modes.
Faceplate Behavior: Rather than prompting for an administrator password, the WinCC SFC faceplate simply renders the AUTO/MANUAL toggle buttons inactive (disabled) whenever the currently logged-in user lacks Level 6 rights.

Step-by-Step Authorization Reassignment Procedure

To adjust authorization levels and restore mode-switching capabilities for Level 5 operators:

Step 1: Open the SFC Configuration in WinCC Explorer

Launch WinCC Explorer on the Engineering Station (or OS Single Station / OS Server).
In the project component tree on the left, locate the SFC editor.
Right-click SFC and select Properties (or double-click to open SFC properties).

Step 2: Modify Authorization Level in the SFC Properties Dialog

In the SFC Properties dialog, navigate to the 'Authorization Levels' tab (or 'Authorizations').
In the list of configurable SFC runtime operations, locate:
* Operating mode / Auto-Manual (or Change operating mode).
Double-click the authorization level entry (currently displaying 6 - Higher process controlling).
Select 5 - Process controlling from the dropdown list.
Review auxiliary SFC operations if required:
* Step control modes: Determine whether manual step transitions should remain at Level 6 or drop to Level 5.
* Setpoints / Parameters: Verify assignment (typically Level 5).
Click Apply and then OK.

Step 3: Compile and Download to OS

Because SFC authorization settings reside within the WinCC project configuration, compile the OS if changes were made on the ES.
In redundant systems or client-server setups, download the project changes to the target OS Servers.
The change takes effect immediately without requiring an Automation Station (CPU) stop or program reload.

WinCC Standard Authorization Levels and SFC Operations Matrix

The following table outlines the relationship between WinCC authorization levels and configurable SFC operational rights in PCS 7:

WinCC Authorization LevelStandard Descriptive RoleDefault SFC Function in V7.xDefault SFC Function in V8.1Recommended Setting for OperatorsLevel 1User administrationNoneNoneAdministrators onlyLevel 5Process controllingAuto / Manual SwitchingParameter entry onlyAuto / Manual SwitchingLevel 6Higher process controllingStep jump / AbortAuto / Manual SwitchingEmergency Stop / Step JumpLevel 7Batch controlRecipe executionRecipe executionSIMATIC BATCH usersLevel 1100Maintenance technicianHardware releaseHardware releaseMaintenance personnel

Aligning authorization levels with plant operational hierarchies prevents unnecessary supervisor callouts.

Verification

To verify that SFC mode switching authorization operates as intended:
1. In WinCC Runtime, log on using a standard operator user account configured with Authorization Level 5 (and lacking Level 6).
2. Open an active SFC faceplate from a process picture or the SFC overview list.
3. Verify that the AUTO and MANUAL pushbuttons are now visually active (enabled with black text and active borders).
4. Click MANUAL: verify that the SFC transitions smoothly to Manual mode, enabling step navigation.
5. Click AUTO: confirm that the SFC returns to Automatic mode.
6. Log out; confirm that with zero users logged on, the buttons return to their disabled, locked states.

Limitations and Operational Precautions

Lowering SFC mode switching to Level 5 allows any standard operator to pause, halt, or take manual control of automated chemical recipes; ensure operational training is provided.
Reassigning authorization levels in WinCC SFC editor applies globally to all SFC instances in that WinCC project; individual chart-level authorization overrides require custom SIMATIC Logon scripts.
Never assign Level 6 permissions globally to generic shift operator accounts simply to bypass SFC buttons, as Level 6 grants authority to override safety interlocks.
If using redundant OS servers, verify that the WinCC User Administrator user database is synchronized across both server nodes.

Engineer FAQ

Do I need to compile the AS in CFC after changing SFC authorization levels?

No. SFC authorization levels are evaluated entirely within the WinCC human-machine interface runtime. Modifying them in WinCC Explorer does not require compiling or downloading the AS.

Why did Siemens elevate the default authorization to Level 6 in PCS 7 V8.1?

Siemens elevated the default level to prevent un-authorized operators from interrupting critical state-based automated sequences or batch operations without supervisor authorization.

Can I configure different authorization levels for individual SFC charts?

By default, the settings in WinCC SFC properties apply to all SFCs in the OS project. Chart-specific restrictions can be enforced in CFC by utilizing SIMATIC BATCH permissions or parameterizing the EN_AUT input.