Unit conversions - Johnson Controls - LIT-1201668 - System Integration - LonWorks Integration - 12.0

LonWorks Network Integration with Network Engines and LCS Technical Bulletin

Brand
Johnson Controls
Product name
LonWorks Integration
Document type
Technical Bulletin
Document number
LIT-1201668
Version
12.0
Revision date
2022-08-30
Product status
Active
Language
English

The Display Units and Field Units attributes define the conversion required to display the Present Value correctly. Table 1 and Table 2 show examples of some valid and invalid configurations. For LON Point Objects that are mapped using the auto discovery process, verify that the Display Units and Field Units attributes are set to the correct units to prevent an incorrectly displayed Present Value. When manually mapping LON Point Objects, take care to correctly set the Display Units and Field Units attributes to prevent an incorrectly displayed Present Value.

Table 1. SNVT_temp_p conversions

Field Units

(Hardware Tab)

Display Units

(Focus Tab)

Valid

Unit Conversion

Custom Scale/ Offset

Deg C

Deg F

Yes

Automatic

Optional

Deg C

Deg C

Yes

No

Optional

Blank

Blank

Yes

No

Optional

Deg F

Gpm

No

Data Conversion Error (temperature to flow)

You can select display units for hardware temperature points on the LN-PRG controllers through the point’s Hardware tab. If Deg F is selected and the network engine is polling a SNVT_count_inc or a UNVT field, the value represents a raw Deg F value; otherwise, the controller displays a raw Deg C value.

Table 2. SNVT_count_inc conversions

Field Units

(Hardware Tab)

Display Units

(Focus Tab)

Valid

Field Data

Unit Conversion

Custom Scale/Offset

Lps

Lps

Yes

200=100 LPS

Disabled

x/2

Lps

Gpm

Yes

200=100 LPS

Yes

x/2

Deg F

Deg F

Yes

831=83.1 Deg F

Disabled

x*0.1

Deg C

Deg F

Yes

252=25.2 Deg C

Enabled

B x*0.1

No Units

No Units

Yes

1000=1000

Disabled

None

Deg F

Gpm

No

831=83.1 Deg F

Data Conversion Error (temperature to flow)