Controlling Devices
This section describes supervisory control sequences that you can use. The following statements apply to all of the sequences:
Each control sequence requires strict adherence to the procedure.
If any action that is not permissible is requested or if any error is encountered when attempting to issue the control, it is reported in a popup box and the sequence is canceled.
If any step of the sequence is not completed within a timeout period, the entire sequence is canceled.
All control actions are recorded in the system event logs.
“Selecting” an object means positioning the cursor over the object (picture, text, etc.) and pressing the left mouse button.
When a particular control is selected, it is checked to see if that control is permitted. Reasons for preventing the control include:
The SCADA Front End is not available.
The control point is not in service.
The control point’s parent is not in service (if this feature is enabled for this type of equipment group).
The control point has a safety tag on it.
The parent equipment group has a safety tag on it (if this feature is enabled for this type of equipment group).
The control point is in the wrong mode (i.e., device under local control).
A control is already pending on the device.
Another control is already active in the same equipment group (if this feature is enabled for this type of equipment group).
The site is not active.
Other conditions in the system block the controls (Interlocks). These conditions are listed in the popup.
Before the command is issued to the SCADA Front End, it is again checked to ensure that current conditions allow the control. Reasons for failing to issue the control are:
A problem occurs when attempting to communicate to the SCADA Front End.
A control is already pending on the same point; try again later.
Controls are temporarily inhibited (i.e., for capacitor valves); try again later.
The control does not exist in the database.
You can perform these procedures from any SCADA one-line diagram display, and from tabular displays for which the control capability has been provided. Supervisory control sequences are described in the following sections.
Controlling Switching Devices from a One-Line
The following procedure is used to operate telemetered controllable switching devices (i.e., valves, capacitor/reactor bank breakers) from a one-line:
From a one-line display, select the switching device symbol.
The device pop-up box appears.
On the pop-up, click the Controls button.
The Control Function popup appears. (Some pop-ups might present switch control as a one-step operation, omitting the Select and Execute steps.)
A flashing “X” indicates that another control is currently blocking this control or the site is not active.
Click the Trip or Close button.
In the pop-up, the Execute and Close buttons become available.
Note: If the device has a restricted tag on it, SCADA notifies the user that an additional Trip or Close action is required to override the restriction tag.
Click the Execute button (or Cancel, if desired).
If control is permitted and successful, the device’s status changes, as depicted on the one-line.
Controlling Switching Devices from a Tabular
The following procedure is used to operate telemetered controllable switching devices (i.e., valves, capacitor/reactor bank breakers) from a tabular:
- On the Substation Tabular display, click the Controls button for the appropriate point.
The Control Function pop-up appears.
A flashing “X” indicates that another control is currently blocking this control or the site is not active.
Click the Trip or Close button.
In the pop-up, the Execute and Cancel buttons become available.
Note: If the device has a restricted tag on it, SCADA notifies the user that an additional Trip or Close action is required to override the restriction tag.
Click the Execute button (or Cancel, to quit at this stage).
If control is permitted and successful, the device’s value on the tabular indicates the new state.
Tap Control from a One-Line Display
The following procedure is used to issue raise/lower controls to transformers from a one-line display.
When raising or lowering taps, be aware that, for some transformers, an alarm is issued if the tap is at its highest, next-to-highest, lowest, or next-to-lowest position.
- On a one-line, select the diamond-shaped transformer raise/lower symbol.
The Raise or Lower Tap pop-up appears.
A flashing “X” indicates that another control is currently blocking this control or the site is not active.
On the pop-up, select the up or down arrows (to raise or lower) as many times as desired, or select Cancel to quit at this stage.
Click the Done button.
The pop-up disappears. The transformer’s new state is indicated on the one-line.
Tap Control from a Tabular Display
The following procedure is used to issue raise/lower or auto/manual controls to transformers from tabular displays.
When raising or lowering taps, be aware that, for some transformers, an alarm is issued if the tap is at its highest, next-to-highest, lowest, or next-to-lowest position.
- On the Substation Tabular display, click the Controls button for the desired transformer.
The Controls Function pop-up appears.
A flashing “X” indicates that another control is currently blocking this control or the site is not active.
Select Raise or Lower, as desired.
The selected control is checked to see if it is prevented.
Select Execute (or Cancel, if desired).
When Execute is pressed, the command is issued to the substation RTU.
Click the Done button.
The pop-up disappears.
Executing Control Groups
This procedure is used to issue a related group of controls in a single command sequence:
- Call up the Group Control display.
Click the Details button for the desired group control.
The Group Control: Execution display appears. The master control is listed at the top of the display and its components are listed below.
Click the Controls button for the master control.
A pop-up displays the valid control options.
Click the Select button, then the desired control, then click Execute (or Cancel, if desired).
When complete, click Done.
If the control is prevented, the sequence is canceled; otherwise, the control is issued to all of the components that are not marked Skip. If Cancel is selected, the sequence is canceled.
Setting Control Skip Status
This procedure is used to indicate whether or not to skip a particular component of a control group when the control group is executed:
- Call up the Group Control display.
Click the Details button for the desired group control.
The Group Control: Execution display appears. The master control is listed at the top of the display and its components are listed below.
In the column labeled Skip, click the button associated with the component that you want to skip (or not skip).
The Skip buttons toggle between the “Skip” and “No Skip” states. The next time this control group is executed, the components in the “Skip” state are not controlled.