Johnson Controls VMA 1410 Installation guide

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

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin2
VMA1400 Series Overview and
Engineering Guidelines
IntroductionThe Variable Air Volume Modular Assembly (VMA) 1400 Series is a
configurable, integrated module that includes a Variable Air Volume
(VAV) controller, differential pressure sensor, and, with the exception
of the VMA1430, an actuator.
Note: This document focuses on the VMA1410, 1420, and 1430
controllers. The VMA1400 Series also includes the VMA1440, which
is used exclusively as part of the Metasys® Zoning Package. See the
Metasys Zoning Package Product Bulletin (LIT-639050) and the
Metasys Zoning Package Overview Technical Bulletin (LIT-639100)
for information on this specialized product.
The VMA engineering procedures vary from location to location. The
information provided here is a general engineering guideline. Where
available, use the Advanced Installation Management (AIM) tools for
developing schedules and drawings.
This document provides a VMA1400 Series overview and describes
how to:
determine VAV box requirements
establish the room schedule
develop bills of material and place orders
configure the VMA

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin 3
Key Concepts
VMA1400 Series Models
VMA1410
VMA1420 VMA1430
VMA14xx
Figure 1: VMA1400 Series Models
The VMA is a configurable, integrated module that includes a VAV
controller and differential pressure sensor. The VMA1400 Series
includes three models:
VMA1410 (cooling only, includes actuator)
VMA1420 (cooling with reheat, includes actuator)
VMA1430 (controller and differential pressure sensor only for use
with an external incremental or proportional actuator)
Note: The VMA1400 Series also includes the VMA1440, which is
used exclusively as part of the Metasys Zoning Package. See the
Metasys Zoning Package Product Bulletin (LIT-639050) and the
Metasys Zoning Package Overview Technical Bulletin (LIT-639100)
for information on this specialized product.
The models are designed for pressure independent, single duct
(all VMA1400 Series models), and dual duct (VMA1420 and
1430 only) applications. The VMA1420 and 1430 models can be used
with parallel or series fan-powered boxes.
Note: The VMA1420 can be configured for the Metasys Zoning
Package application, but the internal pressure sensor can only be used
for monitoring purposes. Refer to the Metasys Zoning Package
Commissioning Technical Bulletin (LIT-639250).

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin4
Table 1: VMA1400 Series Comparison Checklist
VMA Features 1410 1420 1430 Comments
Applications
Pattern Recognition Adaptive
Control (PRAC) on Zone Proportional
plus Integral plus Derivative (PID)
Temperature Loops
Y Y Y Eliminates manual tuning and
seasonal re-tuning
Adaptive Flow Control Loops Y Y Y Eliminates manual tuning,
improves control and energy
savings
Single Duct, Pressure Independent
VAV Y Y Y Meets most VAV applications
Side Loops without Interlocking N Y Y Single Analog Input (AI) to Analog
Output (AO) or Binary Output
(BO)
Single Duct Supply/Exhaust VAV N Y Y Flow differential control
Fan Powered Boxes N Y Y Series or parallel
Incremental, Proportional
Two Position, and Three Stages of
Box Heat
N Y Y Staged heat or normally
open/normally closed valves
Incremental, Proportional
Two Position, or One Stage
Supplemental Heat
N Y Y Normally open or closed valves
Dual Duct, Pressure Independent
VAV N Y Y Flexible flow setpoint specification
Damper Actuator (Internal)
Accurate Positioning Y Y N/A 23,000 step resolution
Stall Detection Y Y N/A Detects damper travel stops
Automatic Damper End Stop
Detection at Power Up Y Y N Sets damper stroke time
Clockwise (CW)/
Counterclockwise (CCW)
Rotation Selection
Y Y Y Set via HVAC PRO™ software for
either direction to close
EP8000 with Pneumatic Actuator N Y Y
Software Tools
Ability To Download Code Firmware Y Y Y Allows firmware code upgrade
without removing the VMA
Diagnostics
Moving Average Flow/Temperature
Diagnostic Y Y Y Provides standard measure of
control loop performance over
time
Actuator Stall Y Y N/A
Flow Test Y Y Y
Data Graphing Y Y Y Only for single duct applications
Starved Box Detection Y Y Y Allows air handler reset and flow
diagnostics
Actuator Duty Cycle Diagnostic Y Y Y Indicates shaft slippage
Continued on next page . . .

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin 5
VMA Features (Cont.) 1410 1420 1430 Comments
Commissioning
Balancing Tool with Automatic
Pickup Gain Calculation Y Y Y HVAC PRO software (single duct
only) or VMA Balancing Tool
(VBT) software on Zone Bus
Hardware
24 Volts Alternating Current (VAC)
Isolation Built-in Y Y Y Eliminates 24 to 24 VAC
transformer and polarity concerns
Multiple VMAs per 100 VA
Transformer Y Y Y Ten cooling only (VMA1410) or
14 VMA1430s. Reheat/fan unit
depends on valve/fan relays
Isolated N2, Binary Outputs, and
24 VAC Y Y Y Saves installed cost and improves
electrical noise rejection
Ability to Drive Low Current Relays
Down to 25 milliampere (mA) N Y Y Eliminates relay chatter
15 Bit Analog Input/12 Bit Analog
Output Resolution AI
only Y Y Provides improved control device resolution
Analog Input Jumpers Eliminated Y Y Y Reduces labor because all analog
inputs are preset
Differential Pressure Transducer
Dead Ended Transducer Y Y Y Requires no filters or maintenance
Stainless Steel Capacitive
Technology Y Y Y Provides improved stability
Industry Accepted Flow
Measurement Accuracy Y Y Y Provides stability below 1 m/s
(200 fpm)
Temperature Sensors
Variety of Sensors Y Y Y Nickel, 1 K platinum, silicon,
2.25K NTC
Temporary Occupied Button Y Y Y On TE-6700, TE-7000 (Europe
only), and TMZ1600 Series room
sensors
Temporary Occupied Light-Emitting
Diode (LED) Y Y Y On TE-6700, TE-7000 (Europe
only), or TMZ1600 for timed
override (Temporary Occupied)
LED Indicator for N2/Power Y Y Y Verifies N2 and power
connections
Physical
Small, One Piece Assembly:
VMA1410, VMA1420
152.4 x 101.6 x 101.6 mm
(6 x 4 x 4 in.)
VMA1430
152.4 x 101.6 x 82.6 mm
(6 x 4 x 3.25 in.)
Y Y Y Reduces installation cost
Plenum Plastic Housing Rating Y Y Y Underwriters Laboratories®, Inc.
(UL) 94-5VB plenum flammability
eliminates metal box
Removable I/O Screw Terminals Y Y Y Two or three position accessories

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin6
VAV System
Theory of Operation
A VAV air handling system typically consists of a single air handling
unit and multiple terminal units. Terminal units typically consist of a
damper and flow sensing probe installed in an enclosure. VAV
terminal units are also called VAV boxes. VAV systems are
predominantly single duct, but about 15% are dual duct designs.
In either case, the supply air temperature and static pressure of the
air handling unit are controlled by an AHU (Air Handling Unit)
controller, while each zone has its own VMA controller.
The air handling unit typically maintains a static pressure in the range
of 125 to 375 Pa (0.5 to 1.5 inches water column (w.c.) inside the
longest run of duct away from the supply fan. This ensures that each
VAV terminal unit has enough pressure at its inlet to deliver the
maximum required flow of air into the space. The supply temperature
is typically in the range of 7 to 16°C (45 to 60°F) for a single duct
VAV system or the cold deck of a dual duct VAV system. The hot
deck temperature of a dual duct VAV system is typically in the range
of 29 to 49°C (85 to 120°F).
VAV systems are most easily understood by first considering a
cooling-only application. As the zone temperature increases, the VAV
controller opens the VAV box damper to allow more cool air to reach
the space. The volume of air required to maintain a particular zone
temperature setpoint is dictated by the size of the space and the
internal and external heat loads. In addition, since the size of the VAV
box dictates its maximum cooling capacity, a VAV box’s performance
is dependent upon the mechanical engineer’s correct box sizing for
each zone.
Sometimes the size, and thus the capacity, of the VAV box may not
match the zone loads. If the installed unit is too small, insufficient
cooling results and noise may be emitted at high flow. If the installed
unit is too large, proper control may be difficult to attain, since a small
change in damper position causes a large change in airflow. Boxes can
be oversized to allow for quieter operation or reserve cooling capacity
at the expense of controllability.

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin 7
The VMA quickly adjusts the damper position to new conditions, and
minimizes position hunting and motor runtime. The fast response
stepper actuator on the VMA1410 and 1420 drives the damper from
full open to full closed in 30 seconds. This significantly reduces the
time to commission a VAV box. Response time of the VMA1430 with
an external synchronous actuator is dependent upon the speed of the
actuator used. The VMA incorporates flow feedback to accurately
position the damper. Control performance metrics are recorded and are
available via the Metasys Operator Workstation (OWS) for timely
indication of system problems.
The VMA is configured for most VAV applications. Configuration
Tools (HVAC PRO software), Version 7.00 or later builds the
applications for VMA1410/1420. Version 7.02 or later includes the
VMA1430 as well as the VMA1410/1420.

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin8
N2
N2
Network
Control Unit
(NCU)
Operator Workstation
Network
Control
Module
(NCM)
Ethernet LAN
DX9100
TC9102
VMA1400
AHU
DX9100
VAV
Room
Sensor
Laptop
Room
Sensor
UNT
Unitary
Controller
(UNT)
V
MA1400
V
MA1400
Zone
Bus
CablePRO
Converter
UNT
VMAMTSY6
N30
N30
Zone
Bus
Palm Compatible
Handheld Device
™
CVTPRO
Converter
Figure 2: VMA in Metasys Network Diagram

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin 9
Definition of Terms
Autocalibration
To correct for pressure sensor drifts over time, the VMA has an
Autocalibration mode that automatically compensates for temperature
and humidity effects.
N2 Switches
Single-pole, single-throw switches used to set the N2 address of a
controller.
Room Schedule
A set of information listing all parameters required in a room or zone.
Test and Balance (TAB)
Test and Balance (TAB) is a function performed to ensure the installed
system operates to design specifications. Balancing of the VMA zone
indicates whether the VAV terminal box is able to achieve
minimum/maximum airflow settings. TAB must also be performed for
the air handler and the air duct distribution to the VAV box.
Zones
When designing VMA systems, it is critical to establish zones
correctly to take full advantage of VMA’s exceptional accuracy and
rapid response capabilities.
The designer strives for the most uniform indoor environmental
conditions possible. A single thermostatic device (room sensor)
controls each area. Also, you may consider a zone any area where the
load is approximately the same for every square foot of floor space.
Heating, Ventilating, and Air Conditioning (HVAC) system zones fall
into two major categories: exterior zones and interior zones. Exterior
zones are spaces directly affected by outdoor weather conditions.
Interior zones are not influenced by heat losses or outdoor air
conditions. Interior zones usually have cooling or ventilation
requirements only.
Further division of interior/exterior zones is occasionally required to
accommodate different occupancy schedules and/or solar loads.
Variations in internal loading also dictate the selection of separate
zones. For example, in a restaurant, the kitchen has much different
heating and cooling requirements than the customer seating area.

VMA1400 Series Overview and Engineering Guidelines Technical Bulletin10
Room Sensor Placement
When considering room sensor placement for each zone:
• Verify that the room sensor is the correct one for the
application.
• Review architectural requirements such as furniture height and
location, aesthetics, and type of mounting. Wall plates are
required if mounting on a conduit handibox.
• Review room sensor location. The best room sensor location is
on an interior wall, about 1.5 m (5 feet) above the floor, out of
direct sunlight, out of the direct path of supply air from the
diffuser, away from heat sources, such as equipment, machines,
and perimeter radiation, and away from doors and other draft
sources. Local codes or disabilities act requirements
occasionally influence the actual mounting height.
• Do not locate a sensor near zone boundaries, where primary
influence is from an adjacent zone.
Pressure Independence
The pressure independent VMA employs patented self-tuning,
cascaded proportional/integral control loops. The zone temperature
loop samples space temperature and resets the airflow setpoint
between the minimum and maximum flow settings. Since inlet duct
static pressure influences the amount of air passing through the VAV
box, the VMA airflow loop samples airflow via a flow pickup in the
box inlet. It modulates the damper to control the flow. Thus, the
VAV box flow is independent of duct static pressure.
The engineering basis for this method of control is that the temperature
of a space with a constant load is linearly proportional to the flow of
conditioned air into the space. The engineer must accurately determine
the required maximum and minimum flow for each space based on
heating, cooling, and ventilation loads.
VMA Airflow Rate
The VMA determines airflow rate by dynamic pressure measurement.
The VMA contains a Differential Pressure Transducer (DPT) to sense
velocity pressure in pressure independent VAV applications.
The DPT is connected to the VAV box airflow pickups. It measures
velocity pressure and generates a proportional voltage signal. The
VMA reads voltage signal from the DPT and converts it to airflow in
cubic feet per minute (cfm), liters/second, or cubic meters/hour.
Calibration is not required, with the exception of zero calibration,
which the controller performs automatically as set in the configuration.