Licensing Entitlements and PO Stacking in Single Station Redundancy 6ES7652-3AA58-2YA0

The SIMATIC PCS 7 V9.0 Single Station Redundancy software package under order number 6ES7652-3AA58-2YA0 includes one WinCC Redundancy license authorization valid for a pair of redundant single stations, bundled with a baseline allocation of 100 OS Runtime Process Objects (OS RT PO) for the master station and 100 OS RT PO for the standby station. Furthermore, these OS RT PO licenses stack additively in Automation License Manager (ALM) with baseline POs supplied by engineering bundles like 6ES7651-5AA58-0YA0 (which includes 250 OS RT POs). Combining both packages expands the active operational capacity of the ES/OS master station to 350 OS RT POs without requiring separate modular expansion licenses.

Architecture of PCS 7 Single Station Redundancy Packages

In SIMATIC PCS 7, small-to-medium industrial plants that require continuous operator visibility without investing in dedicated multi-client server hardware deploy a Redundant Single Station architecture. This topology consists of two independent PC stations running WinCC Single Station software, interconnected via a dedicated Ethernet redundancy link.

Both stations communicate independently with the S7-400 or CPU 410 controllers over the Plant Bus, while WinCC Redundancy continuously synchronizes historical process value archives (Tag Logging), message journals (Alarm Logging), and internal operator tracking data. To authorize this redundant operation, Siemens provides dedicated Single Station Redundancy packages that bundle both the database synchronization software options and base runtime Process Objects.

Entitlement Breakdown of 6ES7652-3AA58-2YA0

The order number 6ES7652-3AA58-2YA0 (SIMATIC PCS 7 Single Station Redundancy V9.0) delivers explicit software license keys via a USB hardware stick or Online Software Delivery (OSD):

WinCC Redundancy Option License: Authorizes bidirectional archive synchronization across two single stations.
Master Station OS Runtime POs: Supplies an initial block of 100 OS RT POs for the primary single station.
Standby Station OS Runtime POs: Supplies a matching block of 100 OS RT POs for the secondary single station.
License Pairing: The single redundancy license key enables the partner synchronization protocol between the two defined PC nodes without requiring separate server-client licensing.

Process Object Stacking and Reconciliation Matrix

The following table demonstrates how license entitlements combine additively when deploying an ES/OS Master and OS Standby:

Software Package / ComponentMaster Station EntitlementStandby Station EntitlementCumulative Master CapacityES Single Station Bundle (6ES7651-5AA58-0YA0)250 OS RT PO + Unlimited ES0 PO (Installed on Master)250 OS RT POSingle Station Redundancy (6ES7652-3AA58-2YA0)100 OS RT PO + Redundancy100 OS RT PO + Redundancy350 OS RT POOptional OS PO Expansion (6ES7658-2XA00-0XB0)100 OS RT PO100 OS RT PO (Must match)450 OS RT POAS RT PO Baseline (From ES Bundle)250 AS RT PO (In Controller)Shared Controller Resource250 AS RT PO

[!NOTE]
Commercial Accuracy Guardrail: Exact software order numbers (MLFBs), Process Object counting rules, and redundancy package combinations must be validated using Siemens Catalog ST PCS 7 and verified through an authorized Siemens distributor. Redundant OS stations must always maintain identical Process Object licensing to prevent synchronization failures.

Managing License Keys in Automation License Manager

To ensure proper license allocation across redundant stations:

Master Station License Distribution:
- On the ES/OS Master station, transfer the PCS 7 Engineering V9.0 license, the WinCC Single Station Redundancy license, the base OS Single Station RT 250 PO license, and the redundancy package's OS Single Station RT 100 PO license to drive C:.
- Automation License Manager aggregates the two OS RT PO keys into a single usable pool of 350 POs.
Standby Station License Distribution:
- On the OS Standby station, install the second OS Single Station RT 100 PO license and the partner redundancy entitlement.
- If the Master station utilizes 350 POs, you must procure additional expansion licenses (6ES7658-2XA00-0XB0 or 6ES7658-2AA58-0YA0) for the Standby station so both nodes possess identical 350 PO capacities.
License Verification in ALM:
- In ALM, select View -> Manage, click drive C:, and verify that the 'Total License Count' matches the sum of all installed Process Objects.

Verification

Verify redundant licensing operation:
1. Start WinCC Runtime on both Master and Standby stations.
2. Check the internal WinCC tag @RedundancyState. Value 1 confirms active, fully synchronized redundancy.
3. In WinCC Explorer, verify that the runtime tag count matches the expected process objects without triggering license warning popups.
4. Deactivate the Master station and confirm that the Standby station assumes visualization duties without displaying license shortfall warnings.

Limitations and Operational Precautions

Asymmetric PO Overrun Risk: If the Master station is licensed for 350 POs but the Standby station is only licensed for 100 POs, the Standby station will enter WinCC Demo Mode upon project download, disrupting operations.
No Multi-Client Capability: Single Station Redundancy packages authorize only the two physical single stations. Remote OS Clients cannot connect without upgrading to full OS Server packages.
Automation License Manager Backup: Always maintain digital backups or license key transfer logs; lost floating license keys require Siemens authorization certificate recovery.

Engineer FAQ

Do Process Object licenses from multiple packages stack automatically in ALM?

Yes. Automation License Manager automatically sums all valid Process Object licenses installed on local drives, allowing base and expansion packages to combine seamlessly.

Does 6ES7652-3AA58-2YA0 include AS Runtime Process Objects for the PLC?

No. 6ES7652-3AA58-2YA0 is strictly an Operator Station redundancy and OS Runtime PO package. AS RT POs are procured separately using packages like 6ES7653-2BA00-0XB5.

Can I use Single Station Redundancy on Windows 10?

Yes. Unlike redundant OS Servers which require Windows Server operating systems, Redundant Single Stations are officially certified to run on Windows 10 Enterprise LTSB / LTSC.

What happens if one redundant single station runs out of PO licenses?

The station with insufficient licenses will display recurring WinCC Demo Mode warning banners and disable historical archiving after the trial period expires.