Controls with Normal Security

In the case of control with normal security, there shall be no additional supervision of the status value by the control object. This means that for the negative case, for example if the status value did not change to the demanded value, the client will not get information about the failure from the control object.

Direct Control with Normal Security

This model shall use the services Operate and Cancel. Direct control with normal security should be used for operations that act either on a local data object (for example, a LED test) or on a data object that influences external devices where returned information is not supervised and independent from any other object (for example, switch on a heating).The below state machine diagram defines the operation.

Select Before Operate (SBO) control with Normal Security

This model shall use the services Select, Cancel and Operate. Once not in the unselected state, only the client that selected the control object shall be able to force state transitions for the control object. All control requests for the selected control object from other clients shall generate a negative response. The below state machine diagram defines the operation.