Trane ZN520, Tracer Unit Ventilator User Manual

Installation
Owner
Diagnostics

Tracer
Unit Ventilator

®

ZN.520 for Classroom

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Installation of New Units

1. Follow all instruction for
installation of classroom unit
ventilators as detailed in UV­IOM-1 (Installation Operation
Maintenance manual).

2. Disconnect power or disable
the circuit breaker to unit.

3. Run communication link wire
when required. (See wiring
diagram in the unit).

4. Install zone sensor when
required. (See wiring diagram
in the unit and zone sensor
submittals).

5. Reapply power.

6. Check for GREEN Status LED
operation to ensure power
has been made to the TracerTM
ZN.520 unit controller.

Start-up Procedures

7. Check for YELLOW Comm LED
operation to help ensure com­munication has been made to
the Tracer ZN.520 unit control­ler when required.

Peel IDENTIFICATION TAG from
unit and place in the Appendix of
this document, or on building
plans for future location use. The
actual room location on the tag
may be hand written.

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Power Up Sequence

Manual output test can be initiated
at any time in the power up se­quence or during normal opera­tion.

When 24 VAC power is initially ap­plied to the controller, the follow­ing sequence occurs:

1. Green Status LED turns on.

2. All outputs are controlled Off.

3. The controller reads input val­ues to determine initial values.

4. Standalone control is assumed
unless occupancy data is com­municated.

5. Random start timer expires (5
to 30 seconds, random).

Start-up Procedures

6. Power-up control Wait feature
is applied. When power up
control Wait is enabled, the
controller waits 120 seconds to
allow ample time for commu­nicated control data to arrive.
If, after 120 seconds, the con­troller does not receive a com­municated occupancy request,
the unit assumes standalone
operation.

7. All modulating valves and
damper calibrate closed, face
and bypass damper calibrate
to bypass (when present).

8. Normal operation begins after
290 (potentially) seconds have
passed.

Note: Manual output test can
be initiated at any time .

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Tracer® ZN.520
Overview

The Trane® Tracer® ZN.520 con­troller is a factory-installed and
commissioned, direct-digital
controller (DDC) offering for
classroom unit ventilator sys­tems. (See Figure 1: “Tracer
ZN.520 Control Board”) The Trac­er ZN.520 can also be applied to
other Trane® interoperable HVAC
equipment, including the fan coil
and blower coil products. (For
more information see, Table 1:

Tracer™ ZN.520 Unit Controller
features and coil availability, on
page 8 for more information.) For

more information regarding the
application of the Tracer ZN.520
to other Trane products, contact
the appropriate local Trane sales
office.

Trane offers a complete solution
to space comfort control with the
flexibility of Integrated Comfort
System (ICS) and stand-alone
control packages. The ICS control
package combines HVAC equip­ment and building management
into one environmental comfort
system.

Integrating the Tracer ZN.520 on
classroom unit ventilators, and
tying them to a Tracer Summit®
system will provide a complete
building management system.
The stand-alone control package
offers the features and function­ality of the direct digital control
without a front-end building au­tomation system, while providing
future considerations for ICS.

Equipment problems can often be
diagnosed on each unit without
having to access the unit compo­nets. These diagnostics can be re­ceived remotely via a modem with
a Tracer Summit building automa­tion system, thus reducing the
number of actual on-site service
calls; through the Rover® service
tool connected to a communica­tion jack located inside the Trace
zone sensor; or connected to the
unit.

General Information

Figure 1: Tracer ZN.520 Control Board

The Tracer ZN.520 is factory­mounted, tested, wired, config­ured and commissioned for the se­lected application.

The Tracer ZN.520 configuration
has flexible point and product con­figurations. For example, with
point configuration, a specific bi­nary point can be configured to ac­cept input from either a time clock
or some type of generic device.

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General Information

Table 1: Tracer™ ZN.520 Unit Controller features and coil availability

Entering

Water

Temperature

Sampling

Coil

Multiple

Fan Speeds

Dehumid-

ification

Auto

Damper

Adjust

Face and

Bypass

Damper

Valve

Control

Economizer

Damper

Auxiliary

2

Heat

2-pipe changeover X X X X X X X
2-pipe hot water

only

X X X X X X

2-pipe steam only X X X X X
2-pipe changeover/

electric heat

X X X X X X X

2-pipe cool only X X X X
2-pipe cool only/

electric heat
4-pipe hot water/

chilled water
4-pipe changeover X X X X
4-pipe steam/chilled

water

1

X

X X X X

X1 X X X

3

3

X X X

X X X X

X X X X X

Electric heat only X X
DX/hot water X
DX/steam X

1

1

1

X

1

X

X X X

X X X
DX/electric heat X X
DX cooling only X

1. Multiple fan speeds are available in hydronic units only.

2. Auxiliary heat is designed to bring on baseboard heat as the second stage of heating. The baseboard heat must be the same type as the

unit heating coil.

3. Units with face bypass dampers cannot actively dehumidify.

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Power

Generic

Controller Circuit Board
Features

Auto Test Button

Status LED

Communications LED

Service Button and LED

Communications

Figure 2: Tracer ZN.520 unit controller circuit board

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Zone Sensor Connections

Controller Features

Each Tracer ZN.520 unit controller
circuit board is equipped with en­hancements to help facilitate ser­vice, testing, and diagnosis.

Each board has

q Manual test button,
q Status LED,
q Communication status LED,
q Service button,
q Quick terminal connectors, and
q Easy to read screen printing.

(See Figure 1: “Tracer ZN.520
Control Board”).

Service

The Trane Tracer ZN.520 unit con­troller is serviced using Rover®, the
ICS software service too. Rover is
designed to support the Tracer
ZN.520 unit controller on the class­room unit ventilator.

For “remote” access to the com­municating units, the zone sensors
offered with the Tracer ZN.520
have a telephone style (RJ-11) con­nector allowing field connection
between Rover and the zone sen­sor; however, the RJ-11 connector
must be connected to the terminals
TB2-5 and TB2-6 on the Tracer
ZN.520 unit controller. (See Figure

3: “Rover service tool connected to
the RJ-11 communication jack in a
zone sensor”)

The zone sensor may also be used
when trying to locate a unit. By
pressing the O N button on the zone
sensor for 5 seconds or using the
“wink” command in Rover, the cir­cuit board receives the signal caus­ing the Communication LED to
“wink”. Winking allows visual
identifier on the board for service
technicians.

The Tracer ZN.520 also includes
features such as a test output to
manually test all of the end devices
and color coded wires (i.e. red for
heating valves and blue for cooling
valves) to aid in the troubleshoot­ing process.(See “Manual Output

Test” on page48, for more infor­mation.)

Figure 3: Rover service tool connected to the RJ-11 communication jack in a zone sensor

Typical Components

A typical classroom unit ventilator
system with a DDC package con­sists of the following physical com­ponents, in addition to the
mechanical equipment:

q Tracer ZN.520—contains the

sensor input circuits, service
adjustments, microprocessor
control electronics, and
communications hardware.

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Power is supplied by a
separately mounted 24 VAC\90
VA transformer.

q Sensor Modules—a variety of

analog sensors that provide
temperature and optional
humidity sensing and CO2
sensor; and an operator
interface to the Tracer ZN.520
for operating modes, status,
and temperature setpoints.

q Standard End Devices—a

variety of devices that help to
gather information, control
capacity, and provide
ventilation are used by the
Tracer ZN.520 in its control
algorithm to condition the
space to the desired
temperature and relative
humidity level. (See “Standard

End Devices ” on page13, for
more information.)

Communication Configurations

Note: The Tracer ZN.520 is a
configured controller. It will
not operate without a valid
downloaded configuration
file.

The Tracer ZN.520 controller sup­ports ICS and peer-to-peer com­munications as well as stand­alone operation. A number of con­trol features may be configured at
the factory or by using the Rover
service tool. (See “Configuration”

on page32, for more information.)

Integrated Comfort
System

Note: The Tracer ZN.520
controller may only be used
with Tracer Summit version

11.0 or greater with a Comm5
communications card.

Classroom unit ventilators can op­erate as part of a large building au­tomation system controlled by
Tracer Summit. The Tracer ZN.520
is linked directly to the Tracer
Summit via a twisted pair commu­nication wire. Each Tracer Summit
building automation system can

connect to a maximum of 120
Tracer ZN.520 controllers.

Figure 4: Communications link wire

The ICS system allows for com­plete communication with the
classroom unit ventilators via
Tracer ZN.520 unit controller. All
points connected to the Tracer
ZN.520 may be observed from the
Tracer Summit front-end control­ler. The Tracer Summit can also
initiate an alarm on a loss of per­formance or equipment malfunc­tions.

The ICS system also allows all of
the classroom unit ventilators to
share information without the
presence of hardwired sensors at
each unit. Some typical shared
points include outside air temper­ature, entering water temperature,
and occupancy schedules.

Peer-to-Peer
Communications

On a peer-to-peer communication
system, multiple Tracer ZN.520
controllers may share data, via a
twisted pair communication wire,
without the need for a Tracer Sum­mit system. (See Figure 5: “Peer-

to-peer communication connec­tions”)

Peer-to-peer communications al­lows features such as master/slave
operation, in which multiple units
operate off of a single zone sensor.
This is typically seen in large spac­es requiring multiple units.

The Rover service tool is required
to set up peer-to-peer communica­tions.

Figure 5: Peer-to-peer communication connections

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Communication Configurations

Stand-Alone

In a stand-alone configuration,
commands for operation are deter­mined based on input from the
zone sensor, humidity sensor, and
factory- or field-mounted time­clock.(See Figure 6: “Typical class-

room unit ventilator installation ”)

q The timeclock is wired to the

Tracer ZN.520 to index the unit
between occupied and
unoccupied modes.

q A unit-mounted, analog,

outside-air temperature sensor
is used to initiate the dry bulb
economizer and freeze
avoidance routines.

q On changeover units, a unit-

mounted, analog, entering
water temperature sensor is
used to automatically control
the system in the heat/cool
mode.

These sensors are required for
proper system operation and are
provided as standard on stand­alone units.

Figure 6: Typical classroom unit ventilator
installation

Communication Interface

Important! To help ensure
optimal performance of the
Rover service tool, please use
the latest version. To obtain
the latest version contact your
local Trane sales represent­tative or service technician.

Note: Refer to the Tracer
system manuals for more
information on communica­tions.

The Tracer ZN.520 communicates
via Comm5 (LonTalk) to a building
management system, the Rover
service tool, and other unit control­lers on the communications link.
Each Tracer ZN.520 requires a
unique address for the system to
operate properly. Every Tracer
ZN.520 has this address (Neuron
ID) embedded in the microproces­sor, which eliminates the need for
field-addressing of the units. Each
unit also ships from the factory
with a unit identification tag. (See

“Location Identifier ” on page38,
for more information.)

Building automation system

Trane offers a state-of the art front­end building automation system
designed to coordinate and moni­tor Trane equipment and control­lers: Tracer Summit.

The Tracer Summit system allows
the user to monitor and/or change
Tracer ZN.520:

q status, parameters, sensor data,

diagnostics, and internal
variables; and

q setpoints, operating modes,

and outputs.

Service tool

Trane also offers a service tool to
work in conjunction with the Tracer
Summit system or with peer-to­peer and stand-alone systems: the
Rover service tool.

Communication to the Tracer
ZN.520, or multiple controllers, can
also be accomplished by using the
ICS software service tool.

A personal computer running Rov­er may be directly connected to a
standalone Tracer ZN.520; con­nected to the communications jack
in the Trane zone sensor; or con­nected to a communicating unit’s
Tracer ZN.520 unit controller, to ac­cess all of the units on a communi­cating link.

Rover allows the user to interface
with the Tracer ZN.520, but will not
allow any advanced control (e.g.
equipment scheduling or trend­ing). To purchase a copy of the ICS
software service tool, contact the
BAS department at your local
Trane dealer.

Interoperability

Trane has lead the industry with
BACnet interoperability and Trane
is now expanding the realm of in­teroperable solutions by offering
LonMark certified unit controllers.
The Tracer ZN.520 controller con­forms to the LonMark Space Com­fort Controller profile. (See

“Appendix—Data Lists” on
page64, for more information.)

This allows the ZN.520 to be used
as a unit controller on other control
systems that support LonTalk and
the SCC profile. Now building own­ers have more choices and design
engineers have more flexibility to
meet the challenges of building au­tomation.

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Standard End Devices

Table 2: End Device Specifications

Device Characteristic Description

Fan Status Switch Material Contact Blade—Pilot duty rated

Operating Temperature Range -40°F/250°F (-40°C/120°C)
Contact Form SPST-NO

Preset Fan status - 0.07”

Low Temperature Detection Switch (Freezestat)

OutsideAir Sensor/discharge AirSensor/Entering
Water Temperature Sensor/Unit Mounted, Zone
Return-air Temperature Sensor

Trip Temperature:

Release Temperature

Rating—Auto Reset

Sensing Element

36°F ± 2°F
(2°C + - 1.11°C)

44°F ± 3°F
(6.67°C + - 1.67°C)

Pilot Duty
(24 VAC)

FLA 10.0 5.0

LRA 60.0 30.0

Thermistor 10 KOhms @ 77°F ± 1.8°F (25°C
±1°C)

120 VAC 240 VAC

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Standard End Devices

Table 2: End Device Specifications

Device Characteristic Description

Outside Air Actuator Description Three-point floating with spring return

Ambient Temperature Rating -25°F to 125°F
Power Consumption 5 VA
Torque 35 in-lbs.

Drive Time 90 seconds, 95 degree stroke

Face and Bypass Actuator Description Three-point floating

Ambient Temperature Rating 32°F to 122°F
Power Consumption 3 VA
Torque 35 in-lbs.

Drive Time 80-110 seconds, 95 degree stroke

2-way Control Valve Description Three-point modulating

Ambient Temperature Rating 140°F at 95% relative humidity
Drive Time 50 seconds
Max Pressure 400 psi water
Close Off Varied by size and Cv

Temperature Water 200°F maximum

14 UV-SVP01A-EN

Standard End Devices

Table 2: End Device Specifications

Device Characteristic Description

3-way Control Valve Description Three-point modulating

Ambient Temperature Rating 140°F at 95% relative humidity
Drive Time 50 seconds
Max Pressure 400 psi water
Close Off Varied by size and Cv

Temperature Water 200°F maximum

Time clock Size 2.83'' x 4.0'' x 2.06''

Power Consumption 4.4 VA
Switch SPDT dry contacts, silver cadmium oxide
Switch Rating 16A 250V resistive, 1000 Watts tungsten
Minimum Switching Current 100mA,230V
Shortest Switching Time 1 minute
Ambient Temperature Range -14°F to 131°F
Wiring Connections Screw terminals suitable for #10 to #24 AWG

Backup Seven day capacitor backup

Zone sensor

Zone Sensor Wiring Size And
Maximum Lengths

16-22 AWG: up to 200 feet

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Standard End Devices

Table 2: End Device Specifications

Device Characteristic Description

Humidity Sensor Sensing Element Polymer capacitive

Sensing Element Accuracy: ± 5% over 20-95% RH @ 77ºF
Range 0 to 99% RH
Operating Temperature Range 0°F to 140ºF
Max Supply Voltage 24VDC
Output Characteristics 4 to 20 MA for 0-100% RH

Drift Rate Less than 1% per year

CO2 Sensor Sensing Element Accuracy: ± 100ppm full scale

Range 0-2000 ppm
Operating Temperature Range 59°F to 95ºF
Supply Voltage 24VAC
Output Characteristics 0-10 VDC for 0-2000 ppm
Power consumption 10 VA

Drift Rate ±5% full scale over four years

Fan Relay

Contact Rating

Terminals 0.25 quick connect
Contact material Silver-Cadium Oxide

Coil 24 vac 2.7 va

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20 amps at 120/240 vac
3/4 hp at 120 vac
1 1/2 hp at 240 vac
20 amps @ 28 vdc
DPDT

Table 2: End Device Specifications

Device Characteristic Description

Control Transformer

Standard End Devices

Type N.E.C. Class 2
Primary Voltage 120 vac

Secondary voltage

24 vac at 90 va
Manual reset
4amp fuse in 24-volt circuit

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Specifications

Dimensions

Tracer ZN.520 board and mounting
hardware:

• Height: 5.25 inches (133 mm.)

• Width: 5.50 inches (140 mm)

• Depth: 2.25 inches (57 mm)

Power Requirements

• 18 to 32 VAC (24 VAC nominal)

• 50 or 60 Hz

• 570 mA AC

Operating Environment

Installation and Wiring

• 32° to 140°F (0× to 60°C)

• 5% to 95% relative humidity,
non-condensing

Storage Environment

• -40° to 185°F (-40° to 85°C)

• 5% to 95% relative humidity,
non-condensing

Agency Listings

• UL and CUL 916 Energy Man­agement System

• Agency Compliance IEC 1000­4-2 (ESD), IEC 1000-4-4(EFT),
IEC 1000-4-5 (Surge)

Figure 7: Tracer ZN.520 circuit board
schematic

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Installation and Wiring

Binary Inputs

Each binary input associates an in­put signal of 0 VAC with open con­tacts and 24 VAC with closed
contacts.

Table 3: Binary inputs (typically 24 mA AC)

Description Terminals Terminal Function

Binary input 1
(BI 1)

Binary input 2
(BI 2)

Binary input 3
(BI 3)

Binary input 4
(BI 4)

J2-1 24 VAC

J2-2 Input

J2-3 24 VAC

J2-4 Input

J2-5 24 VAC

J2-6 Input

J2-7 24 VAC

J2-8 Input

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Binary Outputs

Outputs are load side switching tri­acs. The triac acts as a switch, ei­ther making or breaking the circuit
between the load (valve, damper,
contactor, relay) and ground.

Table 4: Binary outputs

Installation and Wiring

Description Terminals

Fan high J1-1 12 VA

Fan medium,
Exhaust fan

Fan low J1-3 12 VA

No connection J1-4 (Key) — — —
Cool open, face bypass cool valve

DX, 2-position cooling valve, BI 5

Cool close J1-6 12 VA

Face/bypass damper open J1-7 12 VA

Face/bypass damper close J1-8 12 VA

Heat open
Face bypass isolation valve,
2-position heating valve
Electric heat 1st stage

Heat close
Electric heat 2nd stage

Economizer damper open J1-11 12 VA

Economizer damper close J1-12 12 VA

J1-2 12 VA

J1-5 12 VA

J1-9 12 VA

J1-10 12 VA

Output

Rating

Load Energized Load De-energized

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

1 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

24 VAC RMS
(typical)

Generic/baseboard Heat Binary Output

Table 5: Generic binary outputs

Description Terminals Output

Rating

Generic/ baseboard heat output TB4-1 12 VA 1 VAC RMS

24VAC TB4-2 12 VA NA NA

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Load Energized Load De-energized

(typical)

24 VAC RMS
(typical)

Installation and Wiring

Analog Inputs

Table 6: Analog inputs

Description Terminals Function Range

Zone TB3-1 Space temperature input 5° to 122°F

Ground TB3-2 Analog ground NA
Set TB3-3 Setpoint input 40° to 115°F

Fan TB3-4 Fan switch input 4821 to 4919 Ω (Off)

Ground TB3-6 Analog ground NA
Analog Input 1 J3-1 Entering water temperature -40° to 212°F (-40° to 100°C)

J3-2 Analog ground NA

Analog Input 2 J3-3 Discharge air temperature -40° to 212°F (-40° to 100°C)

J3-4 Analog ground NA

Analog Input 3 J3-5 Outdoor air temperature / Generic

temperature

J3-6 Analog ground NA

Analog Input 4 J3-7 Power port 4-20 mA

J3-8 Universal input

Generic 4-20ma
Humidity
CO2

J3-9 Analog ground NA

(-15° to 50°C)

(4.4° to 46.1°C)

2297 to 2342 Ω (Auto)
10593 to 10807 Ω (Low)
13177 to 13443 Ω (Medium)
15137 to 16463 Ω (High)

-40° to 212°F (-40° to 100°C)

0 – 100%
0 – 100%
0 – 2000ppm

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Mounting

The Tracer ZN.520 circuit board is
mounted in the left-hand end pock­et for all classroom unit ventilator
configurations. The sheet metal
mounting plate has raised emboss­es to accept the mounting feet on
the circuit board. (See Figure 8:

“Classroom unit ventilator control
box with close-up of horseshoe
embosses and circuit board
mounting feet. ”) This design al-

lows the Tracer ZN.520 controller
to be secured with a minimal num­ber of sheet metal screws.

Installation and Wiring

Figure 8: Classroom unit ventilator control box with close-up of horseshoe embosses and circuit board mounting feet.

22 UV-SVP01A-EN

Installation and Wiring

The mounting position on the ver­tical classroom unit ventilator

configuration allows complete ac­cess to the Tracer ZN.520 by re­moving the front panel. (See

Figure 9: “Vertical classroom unit
ventilator end pocket”) The

mounting plate swings out of the
way with the removal of a single
screw to allow access to the com­ponents behind the control board.

The mounting plate on the hori-

zontal classroom unit ventila­tor configuration is designed to

slide out with the removal of a sin­gle screw for complete access to
the Tracer ZN.520. (See Figure 10:

“Horizontal classroom unit venti­lator end pocket”) The location of

the control board on this unit con­figuration allows complete access
to the other components in the
end pocket when the front panel is
removed.

For additional convenience, quick
connects and modular wire har­nesses are used on the control
board and mounting plate. (See

Figure 11: “Quick connects to con­trol board in the classroom unit
ventilator”) These quick connects

help facilitate ease of wiring devic­es (e.g., zone sensor) to the control
board, and helps add accessibility
to major components.

Figure 11: Quick connects to control board
in the classroom unit ventilator

Figure 9: Vertical classroom unit ventilator
end pocket

Figure 10: Horizontal classroom unit
ventilator end pocket

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Installation and Wiring

Wiring

!

WARNING

Warning! Disconnect all elec­trical power before servicing
unit to prevent injury or
death due to electrical shock.
Use copper conductors only.
The use of aluminum or
other incorrect types of wire
may result in overheating
and equipment damage.

!

CAUTION

Caution: To prevent damage

to the unit ventilator, refer to
the diagram provided on the
inside of the unit's access
panel for specific wiring infor-

mation. All controls are wired
at the factory. Single point
power, zone sensor, and
communication wiring is to
be installed by the contractor.

Important! All wiring must
comply with state, local, and
federal guidelines. Contact the
appropriate local agency for
furthur information.

Important! Wires for
temperature sensors,
communication lines, 24 VAC,
and contact closure sensing
inputs should not be bundled
with or run near high voltage
wiring.

q Power wiring must be

separated from the Tracer
ZN.520 and all low voltage
wires. External input wires
should be run in separate
conduits from high voltage
wires.

q Wires connected to pin headers

should be formed and routed
so as to cause minimum strain
on the Tracer ZN.520
connector.

q A minimum of 1.5" clearance

(from the pin centerline) for
wires up to 16 AWG is
recommended for bending and
forming wires.

q All sensor and input circuits are

at or near ground potential. Do
not connect any sensor or input
circuit to an external ground
connection.

q A close-coupled ground

connection is required for the
Tracer ZN.520. T

q Table 7: Tracer ZN.520 Wiring

Requirements, shows Tracer
ZN.520 wire types and lengths.

Table 7: Tracer ZN.520 Wiring
Requirements

Application Wire Type Length

Contact Closure 18 AWG

24 VAC 16-22 AWG

Thermostat 16-22 AWG

Zone
Sensor

Communications

16-22 AWG

Belden 8760
or equivalent

Up to
1000 ft.

Up to
1000 ft.

Up to
1000 ft.

Up to
200 ft.

Up to
5000 ft.

Power

The Tracer ZN.520 controller is
powered by 24 VAC. (See Table 7:

“Tracer ZN.520 Wiring Require­ments”)A total of two 1/4-inch

quick-connect terminals are pro­vided for 24 VAC connection to the
board.

Figure 12: Power connection to the Tracer ZN.520 unit controller

24 UV-SVP01A-EN

Installation and Wiring

Installing the Wall­Mounted Zone Sensor
(Optional)

Zone sensor location is an impor­tant element of effective room
control and comfort.

The best sensor location is typical­ly on a wall, remote from the
HVAC unit. Readings at this loca­tion assure that the desired set­point is achieved across the space,
not just near the unit itself.

Note: It may be necessary to
subdivide the zone with
multiple units to ensure
adequate control and comfort
throughout the space.

The following are typical areas
where the zone sensor should NOT
be mounted:

q Near drafts or “dead spots”

(e.g., behind doors or corners);

q Near hot or cold air ducts;

q Near radiant heat (e.g., heat

emitted from appliances or the
sun);

q Near concealed pipes or

chimneys;

q On outside walls or other non-

conditioned surfaces; or

q In air flows from adjacent

zones or other units.

Figure 13: Proper zone sensor placement

Note: All zone sensor wiring
will be done in the factory
unless zone sensor options are
selected to be wall mounted.

When a unit-mounted speed
switch is selected with a wall­mounted zone sensor, the contrac­tor must disconnect the cooling
setpoint on the unit mounted sen­sor if the wall mounted cooling
setpoint is used. The zone signal
will be cut at the factory. The unit­mounted speed switch cannot be
used as a zone sensor.

THe communications link is not
connected in the factory. Commu­nications should be wired to the
wall-mounted sensor.

UV-SVP01A-EN 25

Humidity and CO2 Sensors

Humidity and CO2 sensors should
be mounted in a similar location as
the zone sensor.

Installation and Wiring

Figure 14: Relative humidity sensor

Figure 15: CO2 Sensor

26 UV-SVP01A-EN

Typical Wiring Diagram—Wall
Mounted Zone Sensor

UV-SVP01A-EN 27