The Main Window

This consists of the main drawing area and the toolbar. The main drawing area contains the wiring diagram. See 'Creating an Application' for an example.

NAVIGATION

The visible part of the diagram can be moved within the window in the following ways:

1. By using the up, down, left and right keyboard keys.

2. By using the horizontal and vertical scroll bars

3. In select mode , by holding down the shift key, then click-dragging on the diagram.

4. In Pan mode , by click-dragging on the diagram.

5. By using the Pan tool .

See 'Wiring editor toolbar' for details of these and other tools.

7.4.2 The Tree View

To add a comment to the wiring diagram, click/drag the Comment item from the Tree View to the Main Window.

A text entry box appears to allow the user to enter the comment text, followed by 'OK'. The text entry box closes, and the comment box appears in the wiring diagram at the point at which the mouse button was released.

To link the comment to an item, click on the chain symbol at bottom right-hand corner of the comment box, then again on the destination point. Once linked, the chain symbol disappears, and reappears only when the mouse pointer hovers over bottom right-hand corner of the comment box.

Note: For some devices, new items are drawn with 'dashed' outlines until the file has been downloaded to the device. For all devices, the Link Line is dashed both before and after downloading.

Monitor

Monitor windows are added to the wiring diagram using the same method as described above for Comments (except that the monitor points do not have a text entry window). Monitor windows are linked to the input or output of a function. Once the link is established, the displayed value changes from its initial ???????? to the current value of the input or output point (e.g. PV = 1243.09).

IO IO shows all the IO function block types and the instances in use in the wiring diagram.

Function block types Notes

Where there is only one available instance of a function block type (Instrument for example) the tree cannot be expanded at this point.

If a function block is in use on the diagram it is 'faded' in the tree view.

If all available instances of a block have been used, the block type also becomes faded.

Block names vary from device to device.

To enable a block and make it available for wiring, click-drag either the type, or an instance of it, from the tree to the required position on the diagram. (If the type is dragged, the first available instance of that type will be used.) Once the block appears on the diagram, a context menu becomes available in the tree window, allowing the user to open the iTools Function block view for all the parameters in that block. Function block view can be opened by double clicking on the block, either in the tree or in the diagram, or by clicking the right-hand mouse button over the block, and selecting Function Block View from the resulting menu.

If the active iTools window is not maximised, multiple function block views can be open at the same time.

7.5 Creating an application

When the wiring editor is opened on a connected instrument, the current wiring and diagram layout is read from the instrument.

For models 2604/2704, any changes made in the diagram are downloaded immediately to the instrument. For such devices, new items (e.g. blocks, wires) are drawn with solid outlines. The 'download' key writes the wiring layout to a file on the pc.

For series 3500 devices, EPower controllers and Mini8 controllers, changes made in the diagram have no effect on the block execution or wiring of the actual instrument until the download key is pressed, at which time, the wiring diagram is written to the instrument. For such devices, new blocks, wires etc. are drawn with green, dashed outlines, and deleted items are drawn 'ghosted' and dashed, (and can be 'undeleted'), until the download button is

operated. If changes are made, and the editor is subsequently closed without those changes being saved, a delay will occur whilst the editor clears the changes.

7.5.1 Using function blocks INTRODUCTION

If a function block is not 'faded' in the tree, then it can be dragged into the diagram. Once in the diagram, it can be moved by click-dragging with the mouse, or the selected item can be moved using the keyboard left, right, up and down keys. Blocks can be deleted using the right mouse-click 'context' menu or by operating the <Delete>

key.

A block labelled 'Loop' is depicted below, where 'Loop' is the name of the block instance.

Hovering the mouse cursor over the block, causes 'tooltips' to appear. In the figure below the tooltip for 'Main PV' is shown as an example.

If the Block Type information is editable, clicking on the adjacent down arrow, causes a pop-up window to appear, allowing the user to select or enter a new value:

The inputs and outputs which are commonly of most use appear within the body of the block. Further parameters can be selected by clicking on the 'Select Output' icon at the bottom right of the block.

Generally, for blocks to be of use, parameters must be 'wired' to other parameters. To start a wire from a recommended output, click on the output parameter, then move the mouse cursor to the destination point, and

7.5.2 Block Appearance (3500 series, EPower and Mini8 controllers) DASHED OUTLINE

When first dragged into the diagram, the block is shown with a green, dashed outline. This shows that the block is enabled, but is not yet being executed by the instrument. The block remains in this state, until the wiring diagram is downloaded into the instrument. The block is then added to the instrument function block execution list and is drawn with a solid outline.

If a dashed outline block is deleted, it is removed from the diagram immediately.

SOLID OUTLINE

When the wiring diagram has been downloaded, any dashed items are re-drawn with solid lines. The block is in the instrument's function block execution list, and is being executed.

GHOSTED OUTLINE

Not applicable to all devices.

If a solid outline block is deleted, it remains on the wiring diagram in a dashed and ghosted form, to show that it is still being executed by the instrument. The ghosted image is removed from the diagram, and from the instrument function block execution list, after the diagram has been downloaded to the device.

A ghosted outline block can be 'undeleted' using the right mouse-click 'context' menu.