Control Models

Each control object has an associated control model (ctlModel) that specifies how the control behaves.

The different Control Models available in IEC 61850 are:

• Status Only

• Direct Control with Normal Security

• Select Before Operate (SBO) with Normal Security

• Direct Control with Enhanced Security

• Select Before Operate (SBO) with Enhanced Security

Direct Control or Select Before Operate specifies if a select command is required before operating the control. The select command prevents other devices operating the control while it remains selected.

Normal or Enhanced Security specifies if a command termination message is sent following the control operation. This message is sent by the device and indicates if the control was successful and provides some further information about the control state.

Status Only indicates the control is not currently operable and can only be read.