Johnson Controls VMA18 Series User manual

VMA1826/1832 VAV Controller Installation Guide
Applications
The VMA18 Series programmable VAV box
controllers are intended for use as functional
replacements for the VMA1410, VMA1415, VMA1420,
and the VMA1440 controllers.
VMA1826 controllers are well-suited for commercial
zoning applications and can be used for pressure
dependent VAV box applications where no
differential pressure tranduser (DPT) is required.
Note: At Controller Configuration Tool (CCT)
13.0 or later, using Release Mode 10.1, VMA18
Series controllers can be configured as either
N2 devices or as standard BACnet® MS/TP
devices. This ability provides a potential cost-
effective protocol upgrade path for existing
customers and should be considered when you
install the controller.
Important: When you receive a VMA18 Series
controller from the factory or upgrade the
firmware or main code, the controller defaults
to using the MS/TP communications protocol.
The Load Summary screen of CCT shows the
connection as Wired Field Bus, indicating that
the MS/TP protocol is in use. If you have an N2
application, the Load Summary screen indicates
that you need to switch the communications
protocol to N2.
These VMA controllers feature an integral digital
pressure sensor, a damper actuator, and a 32-bit
microprocessor. The controller's small package size
facilitates quick field installation and efficient use
of space for field replacements, while still enabling
precision control performance.
Note: Connecting an IOM to the VMA via the SA
Bus connection is not supported.
For information about sensor compatibility and
replacement, see Sensor replacement and reuse
scenarios.
North American emissions
compliance
United States
This equipment has been tested and found to
comply with the limits for a Class A digital device
pursuant to Part 15 of the FCC Rules. These limits
are designed to provide reasonable protection
against harmful interference when this equipment
is operated in a commercial environment. This
equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in
accordance with the instruction manual, may cause
harmful interference to radio communications.
Operation of this equipment in a residential area
may cause harmful interference, in which case the
users will be required to correct the interference at
their own expense.
Canada
This Class (A) digital apparatus meets all the
requirements of the Canadian Interference-Causing
Equipment Regulations.
Cet appareil numérique de la Classe (A) respecte
toutes les exigences du Règlement sur le matériel
brouilleur du Canada.
Installation
Observe these guidelines when installing a VMA18
Series controller:
• Transport the VMA controller in the original
container to minimize vibration and shock
damage to the VMA controller.
• Do not drop the VMA controller or subject it to
physical shock.
Parts included
• One VMA18 Series controller with removable N2/
FC bus terminal block
• One installation instructions sheet
• Two 6.35 mm x 6.35 mm (1/4 in. x 1/4 in. ) brass
fittings
*2410143373K*
Part No. 24-10143-373 Rev. K
2019-10-18
(barcode for factory use only)
MS-VMA1826-x, MS-VMA1832-x

• One self-drilling No. 10 x 25 mm (1 in.) screw
• Two 12-in. (30.48 cm.) pieces of flexible tubing
• One controller/sensor Y cable adapter
• One 8-pin to 6-pin single-socket cable adapter
Note: Remove the cap plug from the TSTAT port
of the controller and save for future use. The
cap plug is used on existing sensor ports that
are no longer used.
Materials and special tools needed
Note: You may not require all the materials
listed for your controller installation.
• Several 6 mm (1/4 in.) female spade terminals
for input and output wiring and crimping tool or
spade mounted terminal blocks
• Small straight-blade screwdriver for securing
wires in the terminal blocks
• 8 mm (5/16 in.) wrench or 10 mm (3/8 in.) 12-point
socket to tighten the square coupler bolt
• Several shims or washers to mount the VMA
• Power screwdriver, 100 mm (4 in.) extension
socket, punch, drill, and 3.5 mm (9/64 in.) drill bits
to mount the VMA
• Pliers to open and close the damper
• Required length of 3.97 mm (5/32 in.) ID
pneumatic tubing and barbed fittings
Physical features
Figure 1: VMA18 Series Controller Wiring Terminations and Physical Features
Table 1: VMA18 Series Controller feature callout numbers and descriptions
Physical features: description and references
1 24 VAC, Class 2 Supply Power Spade Terminals (see Supply power spade terminals)
2 Device Address DIP Switch Block (see Setting the device address)
VMA1826/1832 VAV Controller Installation Guide2

Table 1: VMA18 Series Controller feature callout numbers and descriptions
Physical features: description and references
3 Binary Outputs, 24 VAC Triacs (see Table 4)
4 Configurable Outputs: Voltage Analog Output (0–10 VDC) and Binary Output (24 VAC Triac) (see Table 4)
5Dual Port Fitting (see Figure 1)
Not included in the VMA1826 model.
6 Manual Override Switch (see Mounting)
7 Controller Coupler (see Mounting)
8 Coupler Bolt (see Mounting)
9
Universal Input: Voltage Analog Input (0–10 VDC)
Resistive Analog Inputs (0–600k ohm) (see Table 4):
0–2k Potentiometer
RTD: 1k Nickel, 1k Platinum, or A99B SI
NTC: 10K Type L (10K JCI Type II is equivalent to Type L) or 2.252K Type II
Dry Contact Binary Input
10 N2/FC Bus Pluggable Screw Terminal Block (see N2/FC bus terminal block)
11 EOL (End-of-Line) Switch (see Setting the EOL switch)
12 SA Bus Spade Terminals (see SA bus spade lugs)
13 TSTAT Modular Port: RJ-45 8-Pin Modular Jack (see Modular port)
14 Captive Spacer and Screw (see Figure 1)
15 LED Status Indicators (see Table 8)
Mounting
Observe these guidelines when mounting a VMA:
Important: When the air supply to the VAV
box is below 10°C (50°F), make sure that any
condensation on the VAV box, particularly on
the damper shaft, does not enter the VMA
electronics. Mount the VMA vertically above the
damper shaft to allow any shaft condensation
to fall away from the VMA. Additional measures
may be required in some installations.
• Ensure the mounting surface can support the
VMA and any user-supplied enclosure.
• Mount the VMA on a hard, even surface whenever
possible.
• Use shims or washers to mount the VMA securely
and evenly on the mounting surface.
• Mount the VMA in an area free of corrosive
vapors that matches the ambient conditions
specified in the VMA1832 Technical Specifications
section.
• Provide sufficient space around the VMA for cable
and wire connections and adequate ventilation
through the controller (50 mm [2 in.] minimum
on the top, bottom, sides, and front of the
controllers).
• Do not mount the VMA in areas where
electromagnetic emissions from other
devices or wiring can interfere with controller
communication.
• Avoid mounting the VMA on surfaces with
excessive vibration.
• Because the VMA controller is smaller than the
VMA1410, VMA1415, VMA1420, and the VMA1440
controllers, we recommend plugging the unused
open hole with the screw from the original VMA14
mounting when using the VMA18 to replace a
VMA14 Series controller.
On panel or enclosure mount applications, observe
these additional guidelines:
• Do not install the VMA in an airtight enclosure.
• Mount the VMA so that the enclosure walls do not
obstruct cover removal or ventilation through the
controller.
• Mount the VMA so that the power transformer
and other devices do not radiate excessive heat to
the controller.
VMA1826/1832 VAV Controller Installation Guide 3

To mount the VMA18 Series controller, complete the
following steps:
1. Place the VMA18 Series controller in the proper
mounting position on the damper shaft so that
the wiring connections are easily accessible.
Note: The line from the captive spacer and
screw through the center of the damper
shaft must be either horizontal or vertical,
and the wall plate must be wall-mounted
to comply with UL requirements. See the
following figure for possible mounting
positions.
Figure 2: Possible VMA18 Series Controller
Mounting Positions
Make sure the VMA controller base is parallel
to the VAV box (perpendicular to the damper
shaft). If needed, use a spacer to offset tipping
of the VMA controller caused by the shaft
bushings.
Note: Using the alignment marks to center
the captive spacer ensures sufficient
VMA18 controller movement in either
direction.
2. Secure the self-drilling No. 10 screw through
the shoulder washer (Figure 1) with a power
screwdriver and 100 mm (4 in.) extension
socket. Otherwise, use a punch to mark the
position of the shoulder washer, and then drill a
hole into the VAV box using a 3.5 mm (9/64 in.)
drill bit. Insert the mounting screw and tighten
against the washer.
Note: The mounting screw for the VMA
controller does not use the same hole
as the screw for the VMA1410, VMA1415,
VMA1420, and the VMA1440 controller.
We recommend plugging the unused
open hole with the screw from the original
VMA14 mounting when using the VMA18
to replace a VMA14 Series controller.
Important: Do not overtighten the screws,
or the threads may strip. If mounting to
the VAV box, make sure the screws do not
interfere with damper blade movement.
3. Locate the damper position using the typical
marking on the end of the damper shaft. See
the following figure.
Figure 3: Typical damper end shaft icons
4. Note the direction, clockwise (CW) or
counterclockwise (CCW), required to close the
damper. Grasp the damper shaft firmly with
pliers, and either manually close the damper
(for 90° boxes) or manually open the damper
(for 45° or 60° boxes).
5. Push down and hold the Manual Override
button (Figure 1) and turn the VMA controller
coupler until it contacts the mechanical end-
stop at either the fully closed (90° boxes) or
fully open (45° and 60° boxes) position.
6. If the damper for a 90° box closes CCW, rotate
the coupler to the CCW mechanical limit. If the
damper for a 90° box closes CW, rotate the
coupler to the CW mechanical limit. The open
end-stop is automatically set for 90° boxes. For
45° and 60° boxes, hard stops must be provided
at both fully closed and fully open damper
positions. By installing the VMA controller at the
fully open position, the VMA controller provides
the open stop for 45° and 60° boxes. The closed
damper seal provides the fully closed stop.
Important: The integrated actuator has
a stroke time of 60 seconds for 90° of
travel. The stroke time is the amount of
time (in seconds) that it takes the actuator
to move from the fully closed to fully
opened position or from fully open to fully
closed position. For proper operation, the
actuator stroke time must be configured
in the CCT application based on the actual
time it takes the actuator to drive the
damper. The default setting is 60 seconds
VMA1826/1832 VAV Controller Installation Guide4

(for 90° VAV boxes). For 45° and 60° VAV
boxes, the actuator stroke time must be
adjusted. Refer to the Controller Tool Help
(LIT-12011147) for instructions on setting
the actuator stroke time in the application.
7. Tighten the square coupler bolt to the shaft
using an 8 mm (5/16 in.) wrench or 10 mm (3/8
in.) 12-point socket. Tighten to 10.5 to 11.5 N·m
(95 to 105 lb·in).
8. Loop the pneumatic tubing to include a trap for
condensation. If needed, use the included brass
fittings and attach the included pieces of tubing
to the tubing of the VMA controller. Attach the
tubing from the VMA controller to the dual port
fitting on the VMA controller and the other ends
of the tubing to the pressure transducer in the
VAV box application (Figure 1). The VMA1826
does not come with the tubing pieces.
Note: The VMA uses a digital non-flow
pressure sensor with bidirectional flow
operation, which allows the high- and
low-pressure DP tube connections to
be made to either barbed fitting on the
VMA controller. You do not need to make
a specific high- or low-side connection
when you attach the tubing to the barbed
fittings on the VMA.
9. Push the manual release button, and turn the
actuator coupling manually to ensure that the
actuator can rotate from full-closed to full-open
positions without binding.
10. Complete the mounting by rotating the damper
to the full-open position.
CAUTION
Risk of Property Damage
Rotate the damper to the full-open position before
starting the air handler. Failure to rotate the damper to
the full-open position may result in damage to the VAV
box or ductwork when the air handler is started.
ATTENTION
Mise En Garde: Risque de dégâts matériels
Faire pivoter le registre pour le placer en position
d'ouverture complète avant de démarrer l'unité de
traitement d'air. Le non-respect de cette directive
risque d'endommager le caisson de l'unité à volume
d'air variable (VAV) ou le réseau de conduites au dé-
marrage de l'unité de traitement d'air.
Wiring
WARNING
Risk of Electric Shock
Disconnect the power supply before making electrical
connections to avoid electric shock.
AVERTISSEMENT
Mise En Garde: Risque de décharge électrique:
Débrancher l'alimentation avant de réaliser tout rac-
cordement électrique afin d'éviter tout risque de
décharge
Important: Do not connect supply power
to the controller before finishing wiring and
checking all wiring connections. Short circuits
or improperly connected wires can result
in damage to the controller and void any
warranty.
Important: Do not exceed the controller
electrical ratings. Exceeding controller electrical
ratings can result in permanent damage to the
controller and void any warranty.
Important: Use copper conductors only. Make
all wiring in accordance with local, national, and
regional regulations.
Important: Electrostatic discharge can
damage controller components. Use proper
electrostatic discharge precautions during
installation, setup, and servicing to avoid
damaging the controller.
VMA1826/1832 VAV Controller Installation Guide 5

For detailed information on configuring and wiring
an N2 Bus, refer to the N2 Communications Bus
Technical Bulletin (LIT-636018).
VMA terminals and bus ports
See Figure 1 for input and output terminal and bus
port locations on the VMA18 Series controllers.
Observe the following guidelines when wiring a
VMA18 controller.
Input and Output terminals
The input spade terminals are located on the side
of the VMA near the N2/FC Bus terminal block. The
output spade terminals are located on the opposite
side of the controller near the power supply spade
terminals. See Table 4 for more information.
N2/FC bus terminal block
The N2/FC Bus terminal block is a blue, removable,
4-terminal plug that fits into a board-mounted jack.
Wire the removable N2/FC Bus terminal block plugs
on the VMA and other field controllers in a daisy-
chain configuration using 3-wire twisted, shielded
cable as shown in Figure 4. See Table 5 and Table 6
for more information.
Figure 4: N2/FC bus terminal block wiring
Note: The Shield terminal (SHLD) on the N2/FC
Bus terminal block is isolated and can be used
to connect the cable shields on the bus (Figure
4).
SA bus spade lugs
Wire the SA Bus spade lugs on the VMA and other
SA Bus devices in a daisy-chain configuration using
4-wire twisted, shielded cable as shown in Figure 5.
See Table 6 for more information.
Figure 5: SA bus spade lug wiring
Note: Connecting an IOM to the VMA by using
the SA Bus connection is not supported.
Modular port
The modular (TSTAT) port on the face of the VMA
(Figure 1) is an RJ-45, 8-position modular jack used
to connect your new or existing sensor to the VMA
using one of the two included adapters. Refer to
the Sensor Replacement section in the N2 VMA
Application Note (LIT-12011829).
Figure 6: Pin number assignments for the
modular port on VMA18 Controllers
Supply power spade terminals
Wire the 24 VAC supply power wires from the
transformer to the HOT and COM terminals on the
VMA1826/1832 VAV Controller Installation Guide6

spade terminal as shown in Figure 7. See Table 6 for
more information.
Figure 7: 24 VAC Supply Power Spade Terminal
Wiring
Important:
• The supply power terminal block on the
VMA18 is a two-position spade lug (Figure
7). Exercise caution while rewiring the power
plug when replacing an existing controller.
Stray wire strands may make contact and
cause a short circuit across the 24 VAC power
supply.
• To maintain proper phasing when replacing
the existing VMA14xx controller with the
VMA18 controller, connect the power wire
from 24 VAC: 1 terminal on the existing
controller to the HOT power terminal on
the VMA18. Also connect the power wire
from the 24 VAC: 2 terminal on the existing
controller to the COM power terminal on the
VMA18 controller.
The supply power wire colors may be different on
transformers from other manufacturers. Refer to
the transformer manufacturer’s instructions and
the project installation drawings for wiring details.
Important: Connect 24 VAC supply power to
the VMA and all other network devices so that
transformer phasing is uniform across the
network devices. Powering network devices
with uniform 24 VAC supply power phasing
reduces noise, interference, and ground loop
problems. The VMA does not require an earth
ground connection. However, when grounding
the secondary of the 24 VAC transformer
is required, only one connection to ground
should be made near the transformer.
Figure 8: Transformer Grounding
CAUTION
Risk of Personal Injury and Property Damage
Improper wiring of this terminal may cause a short cir-
cuit across the 24 VAC power supply on -1 models.
ATTENTION
Risque de blessure et dégâts matériels
Improper wiring of this terminal may cause a short cir-
cuit across the 24 VAC power supply on -1 models.
To wire the VMA18 Series controller, complete the
following steps:
1. Terminate wiring per engineering drawings.
2. Wire network sensors and other devices to the
VMA's SA Bus.
3. Wire the N2/FC Bus in a daisy chain (see Table
6).
4. Ensure that the VMA’s device address DIP
switches are set to the appropriate device
address. (See Setting the device address.)
5. Connect the VMA controller to 24 VAC, Class 2
power.
Refer to the N2 VMA Application Note (LIT-12011829)
for more information about replacing an existing
controller with an VMA18 controller.
VMA1826/1832 VAV Controller Installation Guide 7

VMA terminal functions, ratings,
requirements, and wiring guidelines
Input and Output wiring guidelines
Table 4 provides information about the functions,
ratings, and requirements for the VMA input and
output terminals, and Table 5 provides guidelines
for wire sizes and cable lengths.
In addition to the wiring guidelines in Table 4,
observe these guidelines when wiring VMA inputs
and outputs:
• Run all low-voltage wiring and cables separate
from high-voltage wiring.
• All input and output cables, regardless of wire
size or number of wires, should consist of twisted,
insulated, and stranded copper wires.
• Shielded cable is not required for input or output
cables.
• Shielded is recommended for input and output
cables that are exposed to high electromagnetic
or radio frequency noise.
• Cable runs of less than 30 m (100 ft) typically do
not require an offset in the input/output software
setup. Cable runs over 30 m (100 ft) may require
an offset in the input/output software setup.
Maximum cable length versus load
current
Use Figure 13 to estimate the maximum cable
length relative to the wire size and the load current
(in mA) when wiring inputs and outputs.
N2/FC and SA bus and supply power
wiring guidelines
Table 6 provides information about terminal block
functions, ratings, and requirements.
Table 6 also provides wire size, cable type, and
cable length guidelines for wiring the VMA
communication buses and supply power.
In addition to the guidelines in Table 6, observe
these guidelines when wiring the SA and N2/FC
Buses and supply power:
• Run all low-voltage wiring and cables separate
from high-voltage wiring.
• All N2/FC and SA Bus cables, regardless of wire
size, should be twisted, insulated, stranded
copper wire.
• Shielded cable is strongly recommended for all
N2/FC and SA Bus cables.
• Refer to the N2 Communications Bus Technical
Bulletin (LIT-636018) for detailed information
regarding wire size and cable length
requirements for the N2/FC and SA buses.
Termination diagrams
A set of Johnson Controls® termination diagrams
provides details for wiring inputs and outputs to
the VMA18 Series controllers. See the figures in this
section for the applicable termination diagrams.
Table 2: Termination details
Type of field device Type of Input/
Output Termination diagrams
Voltage Input -
External Source UI
VMA1826/1832 VAV Controller Installation Guide8

Table 2: Termination details
Type of field device Type of Input/
Output Termination diagrams
Voltage Input - Internal
Source UI
Voltage Input (Self-
Powered) UI
Temperature Sensor UI
Dry Contact UI
0–10 VDC Output to
Actuator (Internal
Source)
CO
0–10 VDC Output to
Actuator (External
Source)
CO
VMA1826/1832 VAV Controller Installation Guide 9

Table 2: Termination details
Type of field device Type of Input/
Output Termination diagrams
24 VAC Triac Output
(Switch Low, External
Source)
CO
Note: Only applies to CO4 and CO5.
Incremental Control to
Actuator (Switch Low,
External Source)
CO
Note: Applies to CO4 and CO5.
Analog Output
(Voltage) CO
24 VAC Binary Output
(Switch Low, Internally
Sourced)
BO
Note: Applies to BO1, BO2, and BO3.
Incremental Control to
Actuator (Switch Low,
Internally Sourced)
BO
Note: Only applies to BO1, BO2, and BO3.
Temperature Sensor
with Modular Jack SA Bus
Note: The bottom jack (J2) on the TE-700 and TE-6x00 Series Sensors are not usable as a
zone bus or an SAB connection.
VMA1826/1832 VAV Controller Installation Guide10