Device redundancy
Configuration
The settings for configuring device redundancy are shown when the checkbox "Redundant device" is activated. In this case the settings for the second device and the tab "Redundancy state" will be available.
If the WinCC OA device is activated, the client tries to establish connection those IEDs, where the checkbox "Connect" (see next paragraph) has been set. On establishing connection the primary IED will be active, the secondary IED passive. If the WinCC OA device is deactivated, the connections to both IEDs will be terminated.
Each single connection of the redundant pair can be enabled or disabled via the respective checkbox "Connect" (See "Parameterization" below) or by setting the data point elements _IEC61850_IED.DeviceRedundancy.Config.ConnectPrimary or _IEC61850_IED.DeviceRedundancy.Config.ConnectSecondary.
The outcome of a switchover is written to the internal data point element _IEC61850_IED.DeviceRedundancy.State.ActiveDevice. The value written is the combination of the following bits:
| Bit | Description |
|---|---|
| Bit 0 | Is set if the first device is active |
| Bit 1 | Is set if the second device is active |
| Bit 2 | Is set if the switchover has failed and is immediately reset afterwards |
| Bit 3 | Invalid switch tag state |
Parameterization
The parameterization is done on the "Devices" tab of the driver cofiguration panel.
Devices
First Device/ Second Device
Enter the IP address and the IED name for the first and second device respectively. Activate the checkbox "Connect" if the client should connect to the respective IED as soon as the WinCC OA device is activated. For details on the configuration, see Devices.
Device switching
Health tag
Address string of the tag which contains the IED's health information. The tag can be selected with the Configure tag button.
The health state is generated by the respective IED. The allowed values can be defined by the user. The client monitors the state of the health tag in a configurable interval (see _IEC61850_IED.DeviceRedundancy.Config.HealthTagInterval). Depending on the user-defined logic, the information on the health tag can be used to trigger a switchover. The logic must decide if the appropriate value shall be written to _IEC61850_IED.DeviceRedundancy.Command.Switchover to trigger the switchover, or the connection to the IED shall be disabled when the IED's health status falls below a defined level.
Switch tag
Address string of the tag which contains the information for device switching. The tag can be selected with the Configure tag button.
The active IED writes TRUE, the passive IED writes FALSE to the address. The WinCC OA IEC 61850 client triggers a switchover when the tag of the active IED changes to FALSE and the tag of the passive IED changes to TRUE. The client monitors the state of the switch tag in a configurable interval (see _IEC61850_IED.DeviceRedundancy.Config.SwitchTagInterval).
Advanced Settings
In case of device redundancy you will get the tabs "First device" and "Redundant device". Configure the settings for each as described on Advanced Settings.
Security
In case of device redundancy you will get the tabs "First device" and "Redundant device". Configure the settings for each as described on Secure Connection.
Redundancy state
Provides state information for both devices and allows triggering a switchover. This tab is only displayed if the option redundant device is enabled.
Primary device / Secondary device
Connection state
Shows the current connection state of the primary / secondary device.
Redundancy state
Shows if the respective device is active or passive.
IED health
Shows the health state if an IED health tag is configured.
IED master
Shows the master/slave state which is received from the respective IED if a switch tag is configured.
Switchover
Allows to manually trigger a switchover to the currently passive IED.
