Application NV Configuration View
Note: This screen displays only those NVs that are used in this
Application.
A Network Variable (NV) is a data item such as a temperature, a switch value or
actuator state. NVs can be thought of simply as point parameters. LonMark functional
profiles define Standard Network Variable Types (SNVTs), but additional non-standard NVs
are usually available, depending on the device, to store additional non-standard data.
There are three categories of NVs that the Lon Spyder supports. They are:
- Fixed_Droppable: You can use Fixed_Dropable NVs while creating an application
logic but can edit only its Internal Data Type. You can also display
Fixed Dropable NVs on the wiresheet.
- Custom: Custom NVs are the NVs you create while creating an application
logic. They can be created, edited, and deleted based on your requirements.
The Honeywell SpyderTool provides the following four built-in functions that enable you
to connect function blocks with other function blocks.
- NVI: Network Variable Inputs
- NVO: Network Variable Output
- NCI: Network Configuration Input
- Many to One NV: Many to One Network Variable
The Honeywell Spyder Tool provides built-in functions, Network Variable Inputs, to
allow the selection of variables that are available from/to the network. The configured
network variables are mapped to the Function Block memory space to be used by any Function
Block. Each Network variable may be configured with a name.
Viewing the List of Network Variables
- Browse to Station > Config > Drivers > LonNetwork > LonSpyder.
- Expand ControlProgram and right-click Application and
select Views > NV Configuration View. The summary page appears with a
list of NVs used in the Program.
The table has the following columns:
- Name: The name of the network variable.
- Type: Indicates if the NV is of type NVI, NVO, NCI or Many to One NV.
- Category: Indicates if the NV is Fixed_Droppable, or Custom.
- NV Container: Indicates the location of the NV.
- Display on WireSheet: Indicates if the NV is displayed on the wiresheet
or not.
- You have options to:
Show Mandatory and Fixed NVs - Click this button to view
list of all Mandatory and Fixed NVs for the selected Spyder model.
Show on wiresheet as points - See the Add NVI,
Add NCI, Add NVO, or Add Many to One NV topics for more details.
Add NV - See the Add NVI, Add NCI, Add NVO, or Add Many to One NV topics for more details.
Edit NV - See the Editing Network Variables
topic for more details.
Delete NV - See the Editing Network Variables
topic for more details.
- The bottom half of the NV Configuration view displays the software
points available on the wiresheet in a tabular format.
The table has the following columns:
- Point Name: The name of the software point (Software Input/Software
Output) as it appears on the wiresheet.
- Field Names: Indicates if the NV is of type NVI, NVO, NCI or Many to
One NV.
- Point Container: Indicates where the software point is used.
Note:
In a Fixed_Droppable NV, only Internal Data Type can be modified.
Custom NV is the user defined NV. A Custom NV can be edited or deleted.
Fixed_Droppable NVs marked as Fixed_Dropable can be exposed on the wiresheet.
Other fixed NVs cannot be exposed as points.
For each point that is copied and pasted on the wiresheet, a new NV of
SNVT type nearest to the selected datatype is created automatically. .