Appendix: Understanding the SCT and Online UI Insert Point Wizard Point Mapping Utility - Metasys - LIT-12011829 - Field Device - VMA18 VAV Modular Assembly

N2 VMA Application Note

Brand
Metasys
Product name
VMA18 VAV Modular Assembly
Document type
Application Note
Document number
LIT-12011829
Revision date
2018-11-01
Language
English

The Insert Point Wizard Point Mapping Utility interprets the information in a PRN resource file to create objects in the Metasys system that are used to monitor the points in the controller. The utility generates a table containing the point objects and folders (used to help organize the objects) that it is located in the PRN file. Here is a description of the columns in the Point Mapping Utility UI:

  • Name: For folders, the name is the folder name from the PRN file. For points, the name is the Short Name from the PRN file. The Short Name is used to conserve space but it can be changed if desired.
  • Object Type: The Point Mapping Utility's best estimate as to which Metasys object to create in order to display the point. The utility works well for most Net Point Types, but sometimes the Object Type requires an update (most often for ADI Net Point Type objects).
  • Net Point Type: The type of point specified in the PRN file. This field should not be updated.
  • Net Point Addr: The point address defined in the PRN file. This field should not be updated.
  • Units: The Point Mapping Utility interprets the unit specified in the PRN file and decides which Metasys unit matches it. The Units column in the PRN file is also used to display States Text sets. If the utility cannot determine which unit to use, this field is blank.
  • States Text: For binary points [BI and BO], the Point Mapping Utility interprets the units in the PRN file as a set name and determines which Metasys States Text set matches the name. The Point Mapping Utility does not handle sets for multistate objects.
Figure 1. Point Mapping Utility

Table 1. Point Mapping Utility Callout Numbers and Descriptions

Callout

Description

1

Points with resolved units

2

Point with no units or states text

3

Points with resolved sets

4

Point with an unresolved unit

5

Point with an unresolved set

In Figure 1, two points in the Units column have drop-down list boxes with no option selected. For the OCCTIME point, which is an ADF Net Point Type, this indicates an unresolved unit. For the OCCSCHED point, which is an ADI Net Point Type, this indicates an unresolved States Text set. Units boxes with no options selected indicate that updates may be required to correctly specify the Metasys object that is created.

PRN files contain some information that is useful only to HVAC PRO (such as Project Information, Question and Answer Session, and Sideloop Definition). PRN files also contain information that defines field device point characteristics that assist in creating objects in the Metasys system. These objects are used to monitor the application in the field device (such as Analog Inputs, Binary Inputs, Analog Outputs, Binary Outputs, and Parameters).

Each section in a PRN file that contains points has a header such as ANALOG INPUTS or VAV Box. These headers are created as folders in the Metasys system, and points are created as children of these folders. Every point in the PRN file has both a long and a short name. The Point Mapping Utility uses the short name when creating a point to save space; however, the names can be changed in the Point Mapping Utility if desired.

Each point in the PRN file is one of seven types: AI, BI, AO, BO, ADF, ADI, or BD. Some types exist in the Metasys system (AI, BI, AO, BO) while the others do not (ADF, ADI, BD). The types that do not exist in the Metasys system must be mapped to a Metasys object type. The Point Mapping Utility in the Metasys UI automatically maps the points to Metasys objects based on the rules in Table 2.

Table 2. Point Mapping Utility Rules

PRN File Point Type

PRN File Point has Monitor Only Asterisk

Metasys Object Type Suggested

AI

 

Analog Input

AO

 

Analog Output

BI

 

Binary Input

BO

 

Binary Output

ADF

Yes

Analog Input

ADF

No

Analog Output

ADI

Yes

Analog Input

ADI

No

Analog Output

BD

Yes

Binary Input

BD

No

Binary Output

Refer to the N2 Integration with the NAE Technical Bulletin (LIT-1201683) for an extensive description of the N2 VMA point mapping procedure.