You can partially modify Fixed Dropable NVs and totally modify Custom NVs. However, you cannot modify Mandatory and Fixed NVs.
Note: If you delete a point of an NV and if this point is the only point in that NV, the NV itself is deleted.
The following table summarizes what you can or cannot do with NVs in the Wiresheet and the NV Configuration View.
| Type | Show NV on wiresheet | Create | Edit | Delete | ||||
| Wiresheet | NV Config View | Wiresheet | NV Config View | Wiresheet | NV Config View | Wiresheet | NV Config View | |
| NVI NCI NVO |
Yes. Any NV added to the wiresheet is automatically displayed on the wiresheet |
Yes. You need to add an NV and select the points you want to be displayed on the wiresheet by clicking the Display on Wiresheet button. |
Yes. You can only add an NV with a single point. |
Yes. You can add an NV with multiple points. |
Yes. You can only edit an NV with a single point at a time. |
Yes. You can edit an NV with multiple points at a time. |
Yes. You can only delete an NV with a single point at a time. NVs of Fixed Dropable type and NVs with Bit Configuration are not deleted but only hidden from the wiresheet. They are still available in the NVs list. |
Yes. You can delete an NV with multiple points at a time. |
| Many to One | Yes. Any NV added to the wiresheet is automatically displayed on the wiresheet |
Yes. You need to add an NV and select the points you want to be displayed on the wiresheet by clicking the Display on Wiresheet button. |
No | Yes. You can add an NV with multiple points. |
No | Yes. You can edit an NV with multiple points at a time. |
Yes. You can only delete an NV with a single point at a time. |
Yes. You can delete an NV with multiple points at a time. |
To edit an NV:
Example: The nciSetPoints is an NV used in the Temperature Set Point Calculator. You can only change its Internal Data Type and the Value.
The following table summarizes editing network variables from the Wiresheet and NV Configuration Views.
| NV Type | Action | From | Procedure |
| NVI/NCI/NVO | Remove points from wiresheet | Wiresheet | You cannot remove (hide) a point from the wiresheet. |
| Remove points from wiresheet | NV Configuration View |
|
|
| Edit NV | Wiresheet | You can only edit individual points of an NV at a time.
|
|
| Edit NV | NV Configuration View | You can edit multiple points of an NV at a time.
|
|
| Delete NV | Wiresheet | You can only delete individual points of an NV at a time. | |
| Delete NV | NV Configuration View | You can delete an NV with multiple points at a time. To delete
an NV with multiple points:
You can also delete individual points in an NV
|
|
| Many to One NV | Remove points from wiresheet | Wiresheet | You can remove (hide) a point from the wiresheet.
|
| Remove points from wiresheet | NV Configuration View |
|
|
| Edit NV | Wiresheet | You can only edit individual points of an NV at a time.
|
|
| Edit NV | NV Configuration View | You can edit multiple points of an NV at a time.
|
|
| Delete NV | Wiresheet | You cannot delete points of a Many to One NV from the wiresheet. | |
| Delete NV | NV Configuration View | You can delete an NV with multiple points at a time. To delete
an NV with multiple points:
|
Note: For special NVs used in function blocks, you can only change the Internal Data Type and the Value. All other fields are unusable. Also, you cannot use the name nciSetPoints to name any other item as it is a reserved name.
Note: If you edit software point details of an NVO, whose points are grouped (shared), all newly created/shared NVOs in which the point is grouped (shared) are modified. You can only edit field names of the points selected to be grouped as NVO. This is true even if the points are added to an existing NVO. However, no information of the existing NVO fields is editable. Only the field names of the newly selected points are editable.
Note: When an NVO is edited such that the details of the field whose exposed point is grouped across multiple NVs are modified, the association of the point with the NV is lost. The point is no longer shared with this NVO. The lower pane in the NV Configuration View does not list this NVO in the list of NVOs to which that point belongs. The modified field becomes local to the NVO and you r must explicitly expose it on the wiresheet to use it in the logic.
To delete an NV:
Note: While deleting an NV, if you select the Retain Points option, points of the NV are converted to invalid points. The option to retain exposed points of deleted NVs is available only from the NV Configuration View. The invalid points are displayed in the lower pane of the NV Configuration View.
If you delete a software point on the wiresheet, the NV to which the point belonged to is modified such that the corresponding field is deleted. The NV itself is deleted if the field happens to be the last field.
Note: In the following cases, deleting a point from the wiresheet puts the
point back in the NV.
If the point is attached to Many to One NVI or Fixed NV
or
if the point is configured as Bit Field
or
if the point is attached to nciTempSetpoints
You can delete an NV without deleting its exposed points. Points of such NVs are converted as invalid points. This option is available only from the NV Configuration view.
You can copy and paste NVs from a source controller to a target controller. When an application folder containing points, but the NV to which it belongs is present in the parent folder of the folder in which the points are present, is copied/cut and pasted to the target controller, the points become invalid.
When an application folder containing NVs whose points are exposed in its parent folder, is cut/copied and pasted to a target controller, the corresponding field (to which the exposed point belonged) is removed from the NV. The NV is deleted if the point happens to be the last field in the controller.
When an application folder containing NVs (containing bit field configuration) whose points are exposed in its parent folder, is cut/copied and pasted to a target controller, the corresponding field (to which the exposed point belonged) is removed from the NV. However, an additional field is added to the NV to make the NV valid.
Note: The tool shall allow grouping of invalid software output points to NVOs.
When the invalid points shall be grouped to form NVs, the invalid points shall be converted to valid software points.
When an invalid software input or an output point is copied and pasted, the resulting point is an invalid point.
When a folder containing some software points (NVI/NCI points) whose NVs are present in other folders (other than its child folders) is deleted, the NV itself is deleted if the point happens to be the last field of the NV.
The following table summarizes how you can convert an NV of a particular type into another type.
| To Convert | To | Configure Point Type as | Configure Share Point on Network as | Result |
| NVI | Constant | Constant | Unselected | Constant |
| NVI | NCI | Constant | Selected | NCI |
| NCI | NVI | Software Input | Selected | NVI |
| NCI | Constant | Constant | Unselected | Constant |
| Constant | NVI | Software Input | Selected | NVI |
| Constant | NCI | Constant | Selected | NCI |