Johnson Controls VMA 1420 User Manual

Technical Bulletin
Issue Date February 28, 2006
Variable Air Volume Modular Assembly (VMA) 1400
Series Overview and Engineering Guidelines
VMA1400 Series Overview and Engineering Guidelines ...................2
Introduction......................................................................................................... 2
Key Concepts...................................................................................................... 3
VMA1400 Series Models...................................................................................................3
VAV System......................................................................................................................6
Definition of Terms............................................................................................................9
Room Sensor Placement ................................................................................................10
Pressure Independence..................................................................................................10
VMA Airflow Rate............................................................................................................10
Power Source..................................................................................................................11
N2 Bus Rules ..................................................................................................................12
Inputs and Outputs..........................................................................................................13
Zone Bus.........................................................................................................................14
CablePRO.......................................................................................................................15
CVTPRO .........................................................................................................................15
Related Documentation...................................................................................................16
Application Examples......................................................................................................17
Reference Information.....................................................................................................26
Specifications..................................................................................................................27
Detailed Procedures......................................................................................... 32
Determining VAV Box Requirements..............................................................................32
Establishing the Room Schedule ....................................................................................32
Developing the Bill of Material and Placing Orders.........................................................33
Configuring the VMA.......................................................................................................35
© 2006 Johnson Controls, Inc. www.johnsoncontrols.com
Code No. LIT-6363120

Johnson Controls VMA 1420 Specifications

General

Model	VMA 1420
Input Voltage	24 VAC ±20%, 50/60 Hz
Number of Universal Inputs	4
Number of Binary Outputs	2
Control Algorithm	PID
Type	VAV Controller
Operating Temperature	-40 to 158°F (-40 to 70°C)
Storage Temperature	-40°F to 158°F (-40°C to 70°C)
Weight	0.6 kg
Communication Protocol	BACnet MS/TP
Temperature Sensor	thermistor type
Product Type	Variable Air Volume (VAV) Controller