Trane Tracer ZN524 Installation Owner Diagnostics

Installation
Owner
Diagnostics

Tracer®ZN524 for
water-source heat pumps

Order No: CNT-SVX11A-EN Date: August 2003

CNT-SVX11A-EN

2 UV-SVN001-EN

Notice

Notice

Warnings and Cautions appear at appropriate sections throughout this manual.
Read these carefully.

- Indicates a potentially hazordous situation
which, if not avoided, could result in death or
serious injury

WARNING

CAUTION

- Indicates a potentially hazordous situation
which, if not avoided, could result in minor or
moderate injury. It may also be used to alert
against unsafe practices.

CAUTION

- Indicates a situation that may result in
equipment or property damage only accidents.

Contents

CNT-SVX11A-EN 3

Start-up Procedures 4
General Information 5
Control Circuit Board Features 6
Control Features 7
Communication Configurations 8
Installation and Wiring 10

Typical Wiring Diagram— 18

Waterside Ecomomizer

Typical Wiring Diagram— 19

Hot Gas Reheat

Configuration 20
Location Identifier 23
Unit Operation 24
Troubleshooting 32
Replacing Circuit Boards 42
Appendix 43
Appendix—Binary Configuration 44
Appendix—Unit Operation 45
Appendix—Data Lists 47
Appendix—Location Identifier 48

Start-up Procedures

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Installation of New Units

WARNING

Hazardous Voltage!

Disconnect all electric power, including
remote disconnects before servicing.
Follow proper lockout/tagout proce­dures to ensure the power can not be
inadvertently energized. Failure to dis­connect power before servicing could
result in death or serious injury.

1. Follow all instruction for installation
of the water-source heat pump as
detailed in the unit’s installation guide.
(Installation Operation Diagnostics
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 Tracer

TM

ZN524 unit controller.

7. Check for YELLOW Comm LED opera­tion to help ensure communication has
been made to the Tracer ZN524 unit
controller when applicable.

8. Write the Unit Identification number,
using the IDENTIFICATION TAG on the
unit, in the Appendix of this document,
or on building plans for future location
use.

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. Stand-alone control is assumed
unless occupancy data is communicat­ed.

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

6. Power-up control Wait feature is
applied. When power up control Wait is
enabled, the controller waits 2-minutes
to allow ample time for communicated
control data to arrive. If, after 2-min­utes, the controller does not receive a
communicated occupancy request, the
unit assumes standalone operation.

7. All valves and damper calibrate
closed.

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

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

General Information

CNT-SVX11A-EN 5

Tracer® ZN524 Overview

The Trane Tracer® ZN524 controller is a
factory-installed and commissioned,
direct-digital controller (DDC) offering
for single or dual compressor water­source heat pump systems. (See Figure
1: “Tracer ZN524 Control Board”)

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 ZN524 on water­source heat pumps 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.

The Tracer ZN524 is factory-mounted,
tested, wired, configured and commis­sioned for the selected application.

The Tracer ZN524 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.

Figure 1: Tracer ZN524 control board

Controller Circuit Board
and Features

6 CNT-SVX11A-EN

Figure 2: Tracer ZN524 unit controller circuit board

A

B

E

D

C

H

F

G

Controller features:

A. Power Connections
B. Generic Connections (BOP)
C. Status LED

D. Auto Test Button
E. Zone Sensor Connections
F. Service Button/LED
G. Communications Connections
H. Communications LED

CNT-SVX11A-EN 7

Controller Features

Each Tracer ZN524 unit controller circuit
board is equipped with enhancements
to help facilitate service, testing, and
diagnosis.
Each board has:

• Manual test button,

• Status LED,

• Communication status LED,

• Service button,

• Quick terminal connectors, and

• Easy to read screen printing. (See
Figure 2: Page 6).

Service

The Trane Tracer ZN524 unit controller is
serviced using Rover®, the software
service tool. Rover is designed to sup­port the Tracer ZN524 unit controller on
a single or dual compressor water­source heat pump.

For “remote” access to the communi­cating units, the zone sensors offered
with the Tracer ZN524 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 communica­tions terminals on the Tracer ZN524 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 on button on the zone sensor
for 5 seconds or using the “wink” com­mand in Rover, the circuit board
receives the signal causing the status
LED to “wink.” Winking allows visual
identifier on the board for service tech­nicians.

The Tracer ZN524 also includes features
such as a test output to manually test
all of the end devices. (See “Manual
Output Test” on page 32, for more infor­mation.)

Typical Components

A typical water-source heat pump sys­tem with a DDC package consists of the
following physical components, in addi­tion to the mechanical equipment:

• Tracer ZN524—contains the sensor
input circuits, service adjustments,
microprocessor control electronics,
and communications hardware. Power
is supplied by a separately mounted
24 VAC transformer.

• Sensor Modules—a variety of analog
sensors that provide temperature and
optional humidity sensing and CO2
sensor; and an operator interface to
the Tracer ZN524 for operating
modes, status, and temperature set
points.

• Standard End Devices—a variety of
devices that help to gather informa­tion and control capacity are used by
the Tracer ZN524 in its control
algorithm to condition the space to
the desired temperature and relative
humidity level.

Note: The Tracer ZN524 is a config­ured controller. It will not operate
without a valid downloaded config­uration file.

The Tracer ZN524 controller supports
ICS and peer-to-peer communications
as well as stand-alone operation. A
number of control features may be con­figured at the factory or by using the
Rover service tool.
(See “Configuration” on page 20, for
more information.)

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

Communication Configurations

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Integrated Comfort System

Note: The Tracer ZN524 controller
may only be used with Tracer
Summit version 11.0 or greater
with a Comm5 communications
card.

Water-source heat pumps can operate
as part of a large building automation
system controlled by Tracer Summit.
The Tracer ZN524 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 ZN524 controllers.

Communications link wire

The ICS system allows for complete
communication with the water-source
heat pumps via Tracer ZN524 unit con­troller. All points connected to the
Tracer ZN524 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
water-source heat pumps 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 ZN524 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 4: Communications link wire

Figure 5: Peer-to-peer communication connections

Twisted pair wire used in
installation of controller in
water-source heat pump

CNT-SVX11A-EN 9

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 repre­sentative or service technician.

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

The Tracer ZN524 communicates via
Comm5 (LonTalk) to a building man­agement system, the Rover service
tool, and other unit controllers on the
communications link. Each Tracer
ZN524 requires a unique address for
the system to operate properly. Every
Tracer ZN524 has this address (Neuron
ID) embedded in the microprocessor,
which eliminates the need for field­addressing of the units. Each unit also
ships from the factory with a unit iden­tification tag. (See “Location Identifier”
on page 23, for more information.)

Building automation system

Trane offers a state-of the art front-end
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
ZN524:

• status, parameters, sensor data,
diagnostics, and internal variables;
and

• setpoints, operating modes, and out
puts.

Service tool

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

Communication to the Tracer ZN524, 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 ZN524; connected to the
communications jack in the Trane zone
sensor; or connected to a communicat-

ing unit’s Tracer ZN524
unit controller, to access
all of the units on a com­municating link.

Rover allows the user to
interface with the Tracer
ZN524, 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.

Stand-Alone

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

• Timeclock can be wired to the Tracer
ZN524 to index the unit between
occupied and unoccupied modes.

• A unit-mounted, analog, leaving
water temperature sensor is used to
initiate the boilerless control or the
optional waterside economizer
routines.

These sensors are required for proper
system operation and are provided as
standard on stand-alone units.
Typical water-source heat pump instal­lation

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 ZN524
controller conforms to the LonMark
Space Comfort Controller profile. (See
“Appendix—Data Lists” on page 47, for
more information.) This allows the
ZN524 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.

Communication Configurations

Figure 6: Standard GEH (horizontal water-source

heat pump) with single control

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Specifications

Dimensions

Tracer ZN524 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

• 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, non­condensing

Agency Listings

• UL and CUL 916 Energy Management
System

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

Installation & Wiring

Figure 7: Tracer ZN524 circuit board schematic

Installation & Wiring

CNT-SVX11A-EN 11

Binary input Pin Location Function Configuration Valid range

BI 1 J2 - 1 24 VAC Low evaporation temperature Normally open

J2 - 2 Input Normally closed

BI 2 J2 - 3 24 VAC Condensate overflow Normally open

J2 - 4 Input Normally closed

BI 3 J2 - 5 24 VAC Occupancy/Generic Normally open

J2 - 6 Input Normally closed

BI 4 J2 - 7 24 VAC Fan status or not used Normally open

J2 - 8 Input Normally closed

1. Trane Rover service tool uses the unit type to help determine and download the proper default binary input configuration.

Binary Inputs

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

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 1: Binary input summary for the J2 terminal board connections

1

Binary Pin Function Valid range Output Load Load

Output Location Rating Energized De-Energized

BOP-1 J1-1 Fan NA 12VA 1 VAC RMS 24 VAC RMS

BOP-2 J1-2 Reversing valve NA 12VA 1 VAC RMS 24 VAC RMS

BOP-3 J1-3 Electric heat or reheat NA 12VA 1 VAC RMS 24 VAC RMS

J1-4 (Key) NA 12VA 1 VAC RMS 24 VAC RMS

BOP-4 J1-5 Compressor 1 Normally open or 12VA 1 VAC RMS 24 VAC RMS

normally closed

2

BOP-5 J1-6 Compressor 2 NA 12VA 1 VAC RMS 24 VAC RMS

BOP-6 J1-9 Isolation valve 1 Normally open or 12VA 1 VAC RMS 24 VAC RMS

normally closed

2

BOP-7 J1-10 Isolation valve 2

4

NA 12VA 1 VAC RMS 24 VAC RMS

BOP-8 J1-11 Economizer valve NA 12VA 1 VAC RMS 24 VAC RMS

BOP-9 J1-12 Outdoor air damper NA 12VA 1 VAC RMS 24 VAC RMS

BOP-10

3

TB4-1/ Generic output NA 12VA 1 VAC RMS 24 VAC RMS

TB4-2

Table 2: Binary output summary

1

1. Trane Rover service tool uses the unit type to help determine and download the proper default binary output configuration.

2. The normally open/closed configuration item refers to the inactive state of the controller output.

3. BOP-10 is a generic output but requires a 24 VAC source for usage.

4. Typical factory installation has only one (1) ISO valve.

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Installation & Wiring

Description Terminals Function Range

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

(-15× to 50×C)

Ground TB3-2 Analog ground NA

Set TB3-3 Local setpoint input 40× to 115×F

(4.4× to 46.1×C)

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

2297 to 2342 V (Auto)
15137 to 16463 V (High)

Ground TB3-6 Analog ground NA

Analog Inputs

Table 3: Analog Inputs (Zone Sensor)

Analog input Terminal Function Range

AI 1 J3 - 1 Entering water temperature or -40 to 2120F (-400to 1000C)

J3 - 2 outside air temperature -40 to 2120F (-400to 1000C)

AI 2 J3 - 3 Discharge air temperature -40 to 212

0

F (-400to 1000C)

J3 - 4

AI 3 J3 - 5 Leaving water temperature -40 to 212

0

F (-400to 1000C)

J3 - 6

AI 4 J3 - 7 Universal 4-20mA input 4-20ma

J3 - 8 Humidity 0-100%
J3 - 9 CO

2

0 - 2000 ppm

Table 4: Analog Inputs with terminal connections

1,2

1. Trane Rover service tool uses the unit type to help determine and download the proper default analog input configuration.

2. Analog input 3 (AI 3) configured as generic temperature input does not affect unit operation. When configured, the TracerTMZN524 unit con-

troller communicates the generic temperature value to Rover or Tracer Summit and displays it as generic temperature.

CNT-SVX11A-EN 13

Installation & Wiring

Mounting

The Tracer ZN524 circuit board is locat­ed in the control box, which is mounted
behind the front panel of the water­source heat pump (See Figures 9 and
10 for more information). The sheet
metal mounting plate has raised
embosses to accept the mounting feet
on the circuit board. (See Figure 8: For
close-up of horseshoe embosses and
circuit board mounting feet.) This
design allows the Tracer ZN524 con­troller to be secured with a minimal
number of sheet metal screws

.

The mounting position on the vertical
water-source heat pump allows com­plete access to the Tracer ZN524 by
removing the front panel - six screws

total. (See Figure 9) Removing the
screws and panel allows access to the
components of the control board.

The mounting plate on both the hori­zontal and vertical water-source heat
pumps allow complete access to the
Tracer ZN524 by removing the front
panel - also six screws total. (See
Figure 10) Removing the screws and
panel allows access to the components
of the control board.

For additional convenience, quick con­nects and modular wire harnesses are
used on the control board and mount­ing plate. These quick connects help
facilitate ease of wiring devices (e.g.,
zone sensor) to the control board, and
helps add accessibility to major compo­nents.

WARNING
Hazardous Voltage!

Disconnect all electric power, including
remote disconnects before servicing.
Follow proper lockout/tagout proce­dures to ensure the power can not be
inadvertently energized. Failure to dis­connect power before servicing could
result in death or serious injury.

Figure 8: A) Cut-away view of the
ZN524 control mounted on the control
box panel. B) Close-up of mounting
shoe on backside of control which slide
into the horseshoe brackets (C) on the
control panel.

Figure 9: Removing front panel of verti­cal unit to access control panel.

Figure 10: Removing front panel of
horizontal unit to access control panel.

A

C

B

14 CNT-SVX11A-EN

Installation & Wiring

Wiring

Live Electrical Components!

During installation, testing, servicing,
and troubleshooting of this product, it
may be necessary to work with live
electrical components. Have a qualified
licensed electrician or other individual
who has been properly trained in han­dling live electrical components per­form these tasks. Failure to follow all
electrical safety precautions when
exposed to live electrical components
could result in death or serious injury.

Use Copper Conductors Only!

Unit terminals are not designed to
accept other types of conductors.
Failure to use copper conductors may
result in equipment damage.

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

• To prevent damage to the unit, refer to
the diagram provided on the unit’s
inside access panel for specific wiring
information. Most control components
are factory-wired. Zone sensors and
communication wiring is to be
installed by the contractor.

• Power wiring must be separated from
the Tracer ZN524 and all low voltage
wires. External input wires should be
run in separate conduits from high
voltage wires.

• Wires connected to pin headers
should be formed and routed so as to
cause minimum strain on the Tracer
ZN524 connector.

• A minimum of 1.5" clearance (from the
pin centerline) for wires up to 16 AWG
is recommended for bending and
forming wires.

• All sensor and input circuits are at or
near ground potential. Do not connect
any sensor or input circuit to an
external ground connection.

• A close-coupled ground connection is

required for the Tracer ZN524.

• Table 5: Tracer ZN524 Wiring
Requirements, shows Tracer ZN524
wire types and lengths.

Power

The Tracer ZN524 controller is powered
by 24 VAC. (See Table 5: “Tracer ZN524
wiring requirements”)A total of two 1/4­inch quick-connect terminals are provid­ed for 24 VAC connection to the board.

Figure 10: Power connections to the Tracer ZN524 unit controller

Application Wire Type Length

Contact 18 AWG Up to
Closure 1000 ft.

24 VAC 16-22 AWG Up to

1000 ft.

Zone 16-22 AWG Up to

Sensor 200 ft.

Communications Belden 8760 Up to

or 5000 ft.

equivalent

ZN524

WARNING

CAUTION

Table 5: Tracer ZN524 wiring

requirements

CNT-SVX11A-EN 15

Installation & Wiring

Installing the Wall-Mounted
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:

• Near drafts or “dead spots” (e.g.,
behind doors or corners);

• Near hot or cold air ducts;

• Near radiant heat (e.g., heat emitted
from appliances or the sun);

• Near concealed pipes or chimneys;

• On outside walls or other non­conditioned surfaces; or

• In air flows from adjacent zones or
other units.

The communications link is not con­nected in the factory. Communications
could be wired to the wall-mounted
sensor if desired.

Figure 11: Proper zone sensor placement

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Installation & Wiring

Zone Sensor Features
Fan Switch (Optional)

The zone sensor fan switch provides
the controller with an occupied (and
occupied standby) fan request signal of
off or auto. If the fan control request is
communicated to the controller, the
controller ignores the hardwired fan
switch input and uses the communicat­ed value. The zone sensor fan switch
signal can be enabled or disabled
through configuration in the ZN524
controller.

ON or CANCEL Buttons

Momentarily pressing the on button
during unoccupied mode places the
controller in occupied bypass mode for
120 minutes. You can adjust the number
of minutes in the unit controller config­uration using Trane’s service tool,
Rover. The controller remains in occu­pied standby mode until the override
timer expires or until the cancel button
is pressed.

Communication Jack

Use the RJ-11 communication jack as
the connection point from Rover to the
communication link (when the commu­nication jack is wired to the communi­cation link at the controller). By access­ing the communication jack via Rover,
entrance to all controllers on the link
may be gained.

Table 6: Zone Sensor Options

Part number:
X13510628010

Description:

• Space temperature
(0.2 C resolution)

• Internal setpoint

• Communication jack

• Vertical case with Trane logo

Part number:
X13510606010

Description:

• Space temperature
(0.2 C resolution)

• External setpoint

• Communication jack

• Vertical case with Trane logo

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Installation & Wiring

Table 6: Zone Sensor Options - continued

Part number:
X13510606020

Description:

• Space temperature
(0.2 C resolution)

• ON and CANCEL buttons

• External setpoint

• Communication jack

• Vertical case with Trane logo

Part number:
X13510635010

Description:

• Space temperature
(0.2 C resolution)

• ON and CANCEL buttons

• Fan switch (OFF and AUTO)

• External setpoint

• Communication jack

• Vertical case with Trane logo

18 CNT-SVX11A-EN

Typical wiring diagram

Figure 12: Wiring

diagram with Waterside
Economizer option

CNT-SVX11A-EN 19

Typical wiring diagram

Figure 13: Wiring

diagram with Hot Gas
Reheat option

20 CNT-SVX11A-EN

Configuration

Table 7: Typical Applications Supported

1

Trane configures the Tracer® ZN524
Unit Controller at the factory per the
selected unit configuration. The con­troller is applied to water-source heat
pumps designed for cooling only or
standard heat pump usage, in both sin­gle or dual-compressor design. The
controller also supports the useage of

water-side economizer, hot gas reheat,
electric heat or boilerless units. Table 7
defines the configuration options sup­ported by the ZN524 controls.

Configurable parameters

Rover service tool uses the unit type to
determine and download many other
aspects of the unit configuration, such
as the default analog input configura­tion, the default binary input configura­tion, and the default binary output con­figuration.

Cooling source

• DX Cooling

• Waterside economizer

Heating source

• None

• Electric heat

• DX Heating

Unit Water-side Hot Gas Electric Boilerless

Economizer Reheat Heat

Cooling Only X

X

X
XX
XX

Heat X

Pump X

X

X
XX
XX
X X

1. Information applies to both single or dual compressor design

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Configuration

Fan configuration Default Valid range

Fan operation in heating Continuous Continuous

1

Cycling with capacity

Fan operation in cooling Continuous Continuous (during occupied)

Cycling with capacity (unoccupied)

Number of fan speeds One 1

Configurable fan speed heating High Off, high, auto

Configurable fan speed cooling High Off, high, auto

Zone sensor fan switch Enable Disable or enable

Table 8: Fan configuration ranges

Setpoint Default Valid range

Occupied heating setpoint 71°F 40 to 115°F

Occupied cooling setpoint 74°F 40 to 115°F
Occupied standby heating setpoint 67°F 40 to 115°F
Occupied standby cooling setpoint 78°F 40 to 115°F

Unoccupied heating setpoint 60°F 40 to 115°F
Unoccupied cooling setpoint 85°F 40 to 115°F

Heating setpoint low limit

1

40°F 40 to 115°F

Cooling setpoint low limit

1

40°F 40 to 115°F

Heating setpoint high limit

1

105°F 40 to 115°F

Cooling setpoint high limit

1

110°F 40 to 115°F

Thumbwheel setpoint Enable Disable or enable

Economizer setpoint 50°F 40 to 100°F

Humidity setpoint 60% 0 to 100%

Table 9: Setpoint defaults

1. The heating and cooling setpoint high and low limits only apply to the occupied and occupied standby setpoints and are not applied to the
unoccupied setpoints.

Table 10: Discharge air limit ranges

Default Valid Range

Low Limit

1

45°F 30 to 50°F

1. The low limit is the temperature at which the controller shuts down the unit to prevent the coil from frosting.

1. Fan will cycle when unoccupied

22 CNT-SVX11A-EN

Configuration

Table 11: Bypass timer range

Default Valid Range

Occupancy bypass timer

1

120 minutes 30 to 240 minutes

( 1-minute resolution)

1. The occupied bypass timer is used for timed override applications.

Occupied Bypass Timer

Table 12: Control wait timer

Default Valid Range

Power up control wait (2 minutes) 120 seconds Disable or enable

Power-up Control Wait

Table 13: Maintenance timer range

1

Default Valid Range

Maintenance timer 0 0 to 10,000 hours

Maintenance Timers

1. Based on fan run hours.

CNT-SVX11A-EN 23

Location Identifier

Unit Identification Tag

The unit identification tag is factory
mounted and provided for easy identifi­cation of an installed unit. It contains
model number, tagging, and location
information.

The unit identification tag remains per­manently affixed to the unit for identifi­cation purposes. The bottom portion of
the tag provides pertinent information
that can be written to in building plans
or in the

“Appendix—Location

Identifier” on page 48.

This provides
identification history about the unit’s
location for quick reference.

These tags provide information about:

• unit serial number (A)

• NID (neuron identification number)—
The NID is similar to the serial number
of the unit but is specific to the identifi­cation of the Tracer ZN524 unit con­troller circuit board (B)

• unit location—The location identifica­tion is a customer defined, clear
English description, of the unit’s physi­cal location. This is a 27 character
description, including spaces, of the
location. For example, if the location
identification for a unit is “Conference
Room 101”, the ZN524, Rover (the Trane
Loop Controller service tool), and Tracer
Summit, will recognize this clear
English description. (C)

If location identification is not defined,
it will default to the unit serial number.
This unit identification tag provides
some information so the user has mul­tiple references to the unit. The blank
location is provided for field modifica­tion in case the unit is moved from the
initial location.

Winking

Winking a device causes the green sta­tus LED on the device selected to blink
at a rate of twice per second for
approximately 10 seconds. This feature
is useful when a discrepancy in device
location exists. As part of the trou­bleshooting process, one person can
wink the device while another can
observe the blinking and verify the
device’s physical location.

Important! If the status LED on the
ZN524 does not blink, the device
may not be communicating or it
may not be the device you selected
according to the stored address.

A Tracer ZN524 unit controller may be
set to wink by pressing zone sensor On
button for 5 seconds and using Rover,
Trane’s communication service tool or
the Tracer Loop Controller.

Figure 14: Water-source heat pump
unit identification tag.

A

C

B

24 CNT-SVX11A-EN

Unit Operation

Power-Up

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

• Green status LED turns on.

• All outputs are controlled OFF.

• The controller reads input values to

determine initial values.

• Random-start timer expires

(5 to 30 seconds).

• When

POWER-UP CONTROL WAIT is

enabled, the controller waits 0-120
seconds (depending on configuration)
to allow ample time for
communicated control data to input. If
the controller does not receive
communi-cated information, stand
alone control is assumed.

• All valves and dampers are closed.

• N

ORMAL operation begins.

Occupancy

The valid occupancy modes for the
Tracer ZN524 controller are:

• OCCUPIED

- Normal operating mode
for occupied spaces or daytime
operation.

• U

NOCCUPIED - Normal operating mode

for unoccupied spaces or nighttime
operation.

• O

CCUPIED STANDBY - Mode used to

reduce the heating and cooling
demands during the occupied hours
when the space is vacant or is
unoccupied.

• O

CCUPIED BYPASS -Used to

temporarily transition the unit from
unoccupied to occupied operation.

The occupancy mode can be hardwired
to the controller via the occupancy
binary input or communicated to the
controller.

O

CCUPIED mode

When the controller is in the

OCCUPIED

mode, the unit attempts to maintain the
space temperature at the active occu-

pied heating or cooling setpoint.

O

CCUPIED mode is the default mode of

the Tracer ZN524 controller.

U

NOCCUPIED

mode

When the controller is in the

UNOCCUPIED mode, the unit attempts to

maintain space temperature at the
stored unoccupied heating or cooling
setpoint (i.e., configurable through
Tracer Summit or the Rover service
tool) regardless of the presence of a
hardwired or communicated setpoint.
When the space temperature exceeds
the stored unoccupied setpoint, the
controller brings on 100% of the pri­mary heating or cooling capacity.

The

UNOCCUPIED mode can be initiated

through a hardwired signal to the occu­pancy binary input or by a communi­cated request.

O

CCUPIED STANDBY mode

The

OCCUPIED STANDBY mode allows the

unit to operate at a heating or cooling
setpoint between the occupied and
unoccupied setpoints to help maintain
the environment while decreasing ener­gy consumption.

This mode can decrease the energy
consumption for heating or cooling
during brief periods of vacancy in the
space. Unit operation in this mode is
similar to the occupied mode except for
the different heating and cooling set­points.

The

OCCUPIED STANDBY mode is initiated

only when occupancy is communicated
to the Tracer ZN524 controller and the
hardwired signal to the occupancy
input is calling for unoccupied opera­tion.

O

CCUPIED BYPASS mode

The OCCUPIED BYPASS mode is used to
transition the unit from the UNOCCUPIED
mode to the occupied mode for a peri­od of time from 0 to 4 hours (config­urable through Rover. Default=2 HRS).

The controller can be placed in

OCCUPIED BYPASS mode by either com-

municating an occupancy request of
bypass or by using the

TIMED OVERRIDE

(i.e., ON) button on the Trane zone sen­sor.

O

N and CANCEL Buttons

Some Trane zone sensors have ON and
C

ANCEL buttons for timed override

operation. Pressing the On button on
the zone sensor when the unit is in the

UNOCCUPIED mode initiates the
OCCUPIED BYPASS mode and initializes

the bypass timer. The cancel button is
used to send the unit back into

UNOCCUPIED mode before the bypass

timer has expired.

The On button may also be used for the
unit identification or the “WINK” fea-
ture. When the Tracer ZN524 controller
is connected to a Tracer Summit sys­tem, Loop Controller, or the Rover serv­ice tool, the On button may be used in
place of the service pin for easy unit
identification.

Heating And Cooling
Changeover Logic

The Tracer™ ZN524 Unit Controller can
receive communicated requests for
heating or cooling operation. The com­municated variable nviApplicMode is
used to communicate the requests for
the controller's operating mode based
on the following values:
0 = Auto (mode determined by con­troller)
1 = Heat (uses heating setpoints)
2 = Morning Warm-up
3 = Cool (uses cooling setpoints)
5 = Pre-cool (morning cool down)
6 = Off (no unit operation allowed)
7 = Test (special test mode)
9 = Fan Only (no heating or cooling)

CNT-SVX11A-EN 25

Unit Operation

All other numers will be interpreted as
Auto.

As the controller automatically deter­mines its heating or cooling mode, it
changes from cool to heat or from heat
to cool, while the error (integrated over
time between the active setpoint and
the space temperature) is (900

°F • Sec).

Integration only begins once the heat­ing and cooling capacity is equal to 0%
(See Figure 15).

Heat/Cool Changeover Logic

If the measured space temperature is
69

°F and the active cooling setpoint is

72

°F, the error between the space tem-

perature and the setpoint is three
degrees. If the same error exists for one
minute (60 seconds), the integration
term is (3

°F • 60 Sec) or (180°F • Sec).

The Tracer™ ZN524 Unit Controller
changes from heating to cooling and
cooling to heating when the integration
term exceeds (900

°F • Sec). Along with

satisfying the integration for heating
and cooling changeover, the measured
space temperature must fall outside the
setpoint range. This means the space
temperature must be greater than the
active cooling setpoint or lower than
the active heating setpoint.

Example: If the cooling setpoint is 75

°F

and the heating setpoint 70°F, any space
temperature greater than 75

°F or less

than 70

°F is outside the setpoint range.

Once the integration term is satisfied
and the space temperature is outside
the setpoint range, the controller
changes modes. However, before the
unit's heating or cooling capacity
ramps up, the controller checks to make
sure it is capable of heating or cooling.

In instances where waterside
economizers or boilerless controls are
in use, it is necessary to verify the
water temperature before unit opera­tion is allowed.

Figure 15: Heat/Cool Changeover logic

26 CNT-SVX11A-EN

Unit Operation

Cooling Operation

During the COOLING mode, the Tracer
ZN524 controller attempts to maintain
the space temperature at the active
cooling setpoint, which is one of the
following:

• Occupied cooling

• Occupied standby cooling

• Unoccupied cooling

The controller uses the measured space
temperature, the active cooling setpoint
along with the control algorithm to
determine the requested cooling capac­ity of the unit (0-100%). The outputs are
controlled based on the unit configura­tion and the requested cooling capacity.

Heating Operation

During the heating mode, the Tracer
ZN524 controller attempts to maintain
the space temperature at the active
heating setpoint, which is one of the
following:

• Occupied heating

• Occupied standby heating

• Unoccupied heating

The controller uses the measured space
temperature, the active heating setpoint
along with the control algorithm to
determine the requested heating capac­ity of the unit (0-100%). The outputs are
controlled based on the unit configura­tion and the requested heating capacity.

Fan Operation

The Tracer ZN524 controller also allows
the fan speed to be configured as auto.
When the fan speed switch is in the
auto position and the default fan speed
is configured as auto, the unit may
change between cycling and continu­ous, depending on how the default fan
speeds are configured for heating and
cooling modes.

The fan mode request can be either
hardwired or communicated to the
Tracer ZN524 controller. When both are
present, the communicated request has
priority over the hardwired input.

During o

CCUPIED, OCCUPIED STANDBY,

and

OCCUPIED BYPASS modes, the fan

will operate as configured (cycling or
continuous). The fan may be controlled
off in these mode when the MANUAL

OUTPUT TEST

has been initiated, a latch­ing diagnostic is present, or the com­municated or hardwired fan speed is
off.

During the UNOCCUPIED

mode, the unit

fan is controlled off. When capacity is
required to maintain the U

NOCCUPIED

heating or cooling setpoint, the unit fan
is controlled on until the UNOCCUPIED
setpoint is satisfied.

Fan Off Delay

If the fan is configured for cycling and
the heating output is controlled off, the
Tracer ZN524 Unit Controller automati­cally holds the fan on for an additional
30 seconds. This 30-second delay gives
the fan time to blow off any residual
heat from the heating source.

Entering Water Temperature
Sampling Function

The Tracer ZN524 controller will sample
the Entering Water Temperature (EWT)
to determine proper control action for
units equipped with boilerless electric
heat or Waterside Economizer (WSE).
Each unit is treated as having isolation
valves - whether present or not. If the
EWT is communicated to the controller
via a BAS system, then no sampling
will be required.

If the EWT is present as a hardwired
input and communicated from a BAS,
the communicated value will be used.
When the EWT sample is used, the iso­lation valve on circuit 1 will be driven
open for 3 minutes and the EWT read­ing will be taken at that time.

To avoid sampling each time a new
cooling/heating request is initiated, the
last EWT value recorded is used for the
next (1)hour. During boilerless control
heating, if setpoint has not been met
following the hour, a new EWT reading
is made and the appropriate control
action is taken.

During WSE and DX operation, the EWT
is refreshed as often as the analog
imput is polled. NOTE: If the WSE is dis­able due to enable setpoint AND DX
cooling is in operation, DX cooling will
not be disabled until the load is met.
This will occur even if the EWT has
lowered to the point the WSE can be
used. Refer to the WSE documentation
for further details.

Sampling for Waterside Economizer
Units

EWT is used to determine if WSE opera­tion is feasible. If the EWT meets the
configured Enable setpoint, WSE opera­tion is possible.

CNT-SVX11A-EN 27

Unit Operation

EWT sampling will be invoked when
the following conditions have been
met:

• EWT is not communicated via a BAS
and:

• Unit is equipped with a WSE

The the following must occur:

• There is a new control request for
cooling and isolation valve 1 is not
open and more than 1-hour has
elapsed since the last EWT sample

When these conditions are met, circuit
1 isolation valve is opened for 3-min­utes and the EWT reading is taken and
WSE operation feasability is deter­mined. The isolation valve will remain
open regardless.

Sampling for Electric Heat
Units

For units equipped with electric Heat
and configured for boilerless control,
EWT is used to determine whether DX
heating should be disabled and electric
heat enabled. EWT sampling is invoked
when the folowing conditions are met:

• EWT is not communication via a
BAS and:

• Unit is equipped with electric heat
configured for boilerless control and
is not a cooling only unit

Then the following must occur:

• There is a new control request for
heating and isolation valve 1 is not
open and more than 1-hour has
elapsed since the last EWT sample
or:

• Boilerless electric heat is running
and more than 1-hour has elapsed
since the last EWT sample

When these conditions are met, circuit
1 isolation valve is opened for 3-min­utes, the EWT reading is taken and
electric heat operation feasability is
determined. If boilerless electric heat is
enabled, the isolation valve will be
closed, halting water flow to the unit.

The following chart provides a quick
reference to unit configurations in
which EWT is enabled:

Water-side Economizer
Operation

The ZN524 supports the use of a 2-posi­tion Water Side Economizer (WSE). The
WSE is only active in cooling mode and
the EWT setpoint has been met. If the
zone requires cooling and the WSE is
enabled, the WSE valve will open and
begin controlling the zone. If the WSE
capacity can not cool the zone, then 1­stage of compressor cooling will be
allowed to operate with the WSE. The
second stage of compressor cooling
will not be allowed to run, under any
circumstances, when the WSE is in
operation. Note: If the zone tempera­ture continues to rise, the WSE enable
setpoint may need to be redueced in
order to increase unit capacity.

When the WSE and the compressor are
running simultaneously, coil frosting
may occur. The ZN524 controls two
devices to prevent this from occuring.

Coil Icing Protection

A fixed temperature device is mounted
to the evaporator coil and wired to a
binary input on the ZN524 controller.
When the binary input on the ZN524

trips ( in alarm situations) the following
actions will occur:

Note: The fan will remain on during
this operation

This low-level diagnostic will automati­cally rest when the binary input
changes to the normal state. The com­pressor minimum on and off times (3
minutes) will be enforced during this
mode.

Low Leaving Air Protection

This mode is activated during WSE
operation and controlled by the dis­charge air sensor. If the discharge air
temperature drops below 45 F for 1­minute while the unit is economizing,
the following actions will occur:

Note: The fan will remain on during
this operation

This low-level diagnostic will reset
when the discharge air temperature has
risen above 50 F. The compressor mini­mum on and off times (3 minutes) will
be enforced during this mode.

EWT

Sampling

Enabled

Unit Build Configuration

No Heat pump (HP)

Yes HP with WSE

Yes HP + electric heat (boilerless)

Yes HP + electric heat + WSE

No HP + electric heat (concurrent)

Yes HP + electric heat (concurrent) + WSE

No Cooling only

Yes Cool only with WSE

No Cool + electric heat (boilerless)

Yes Cool + electric heat (boilerless) + WSE

Cooling Mode Control Action

Economizer None

Economizer & 1-stage DX Disable 1st Stage DX

1st and 2nd stage DX

Disable DX

stages 1 and 2

Cooling Mode Control Action

Economizer None

Economizer & 1-stage DX Disable 1st Stage DX

1st and 2nd stage DX None

28 CNT-SVX11A-EN

Unit Operation

Electric Heat Operation

The Tracer ZN524 supports 1-stage elec­tric heat in one of three ways:
Supplemental, Boilerless and Main
heat.

Supplemental

When applied, the electric heat is
cycled on as the last stage of heating.
Compressor 1 and 2 (where applicable)
will be energized and the electric heat
will operate concurrently with the com­pressors as needed to maintain space
temperature.

Boilerless

When applied, the electric heat will be
enabled based on EWT. The compres­sor(s) and electric heat is not allowed to
operate at the same time. Boilerless
electric heat is controlled by the EWT
and compressor heat disable setpoint.
If the unit is in the heating mode and
the EWT falls below the compressor
heat disable setpoint, then the com­pressor will be disabled for heating and
the electric heat will be cycled to main­tain temperature.

Boilerless control will be disabled if the
EWT rises 5 F above the compressor
heat disable setpoint. The EWT value
can be either local or communicated. In
applications where the local water sen­sor is used, the unit may utilize the
Entering Water Temperature Sampling
function to verify water temperature.

Main Heat

The electric heat will be utilized as the
only form of heat for the unit. The com­pressor and electric heat will not oper­ate at the same time. When in the heat­ing mode the electric heat cycle to
maintain space temperature.

Compressor (DX) Cooling

The ZN524 controller supports two
stages of DX cooling. The control is pro­portional and based on an error rate of
3 F for single compressor operation
and 5 F for 2-compressor units. Zone
temperature is compared against active
setpoints for compressor operation:

O

FF, pulse width modulation or ON.

Note: When the control is in the
dehumidification mode only O

FF

and ONare valid compressor
states.

At start-up or during mode transition, if
both compressors are requested to run,
compressor 1 will be energized first.
Compressor 2 waits until the next con­trol cycle (10 seconds) to energize.

Water Isolation Valves

The ZN524 supports the operation of
water isolation valves for varialble
speed pumping systems. Up to 2 isola­tion valves are supported, one for each
compressor circuit. The valves are
spring return and normally closed. The
ZN524 operates as if isolation vlalves
are present. The presence or absence of
isolation valves is not a configuration
factor.

Under normal operation, the ZN524
opens the isolation valve(s) under the
following conditions:

• DX Heating request

• DX Cooling or WSE request

• When control is in DX heat or cool
mode AND is controlling with pulse
width modulation, the valves will
remain open during the pulse width
modulation cycle.

• Dehumidification request

• EWT sampling request. Valves will
remain open for 3 minutes.

• Manual testing

• During DX operation. The valves will
open for 20 seconds to ensure
adequate water flow before
energizing the compressor outputs.

• Upon opening, the valves remain
open for a 10 minute minimum to
reduce excessive valve cycling.

Note: If only a single isolation
valve is used on a two-circuit heat
unit, it must be wired to the isola­tion valve 1 output.

Isolation valve 1 must remain open as
long as the control is in an active cool­ing, heating, or dehumidification. If cir­cuit/compressor 1 is taken off-line, iso­lation valve 1 will remain open to allow
operation of circuit 2.

Under normal operation, isolation
valves will be closed under the follow­ing conditions:

• Compressor and WSE are controlled

O

FF

and the 10-minute minimum on
has expired. Note: If the WSE is
disabled due to economizer enable
paramenter or through BAS system
and cooling demand is still present,
the isolation valve will remain open
for compressor operation.

• Isolation valve 2 will close if
compressor 2 is taken off-line due to
a diagnostic or no capacity call and
the 10-minute minimum on has
expired

• Power is lost, valves de-energize to
the closed position

• Manual test off

There is no time delay when an isola­tion valve is to be closed. The ouptut
will be de-energized and the valve will
spring return closed.

CNT-SVX11A-EN 29

Unit Operation

Other Modes

DEHUMIDIFICATION

The ZN524 controller controls the zone
to the active cooling setpoint using pro­portional control. The ZN524 also con­trols one stage of DX cooling in con­junction with one stage of reheat. The
only supported dehumidification type
during this period is hot gas reheat.

The factory-supplied ZN524 supports
one binary output for the control of a
two-position hot gas reheat solenoid
valve. This valve is normally closed and
will open when energized providing the
flow of hot refrigerant gas through the
reheat coil. The reheat coil is sized to
provide neutral air at 75 F loop condi­tion with 75 F dry bulb return air at 75%
relative humidity. When in the dehu­midification mode, only the first stage
DX cooling will be allowed to run on
two stage units.

Active dehumidification can only occur
when the controller is in the cooling
mode. Active dehumidification is not
allowed in heating mode.
Dehumidification can be active during
all time of day schedules.

A humidity transmitter is used to meas­ure the zone relative humidity and is
compared against the relative humidity
enable/disable setpoints. Relative
humidity level can be communicated to
the ZN524 from a Tracer Summit sys­tem. The default values for dehumidifi­cation enable is 60% relative humidity.
Disable point is 52% relative humidity.
These values are configurable.

To avoid subcooling the space if the
reheat is not sized properly or during
certain system conditions, a low limit
temp is established to exit dehumidifi­cation mode. The low limit is the active
cooling setpoint in the O

CCUPIED and

UNOCCUPIED standby modes.

In the U

NOCCUPIED

mode, the default

O

CCUPIED cooling setpoint is used as the

low limit. This enables extended dehu­midification during unoccupied modes
which allows sub-cooling the space to
the default O

CCUPIED setpoint. If the

zone temperature reaches the low limit
the DX cooling and reheat will be
turned off. The zone temperature must
then rise 0.75 F above the low limit
before the DX cooling and reheat are
allowed to operate again.

Note: While in the dehumidification
mode, if there is a call for capacity
by the unit, the zone temperature
setpoint will take priority over the
relative humidity setpoints.

Dehumidification will occur during the
following:

• Unit mode = cooling

• Relative humidity > Enable setpoint

Reheat in the dehumidification mode is
utilized under the following conditions:

• Zone temp is above the active
cooling setpoint

• Zone temp error < 1.5 F above the
active cooling setpoint

The compressor will be energized 100%
of the time during dehumidification
mode. No pulse width modulation is
used during dehumidification.

Dehumidification will occur during the
following:

• Unit mode = cooling

• Relative humidity > Enable setpoint

Reheat in the dehumidification mode is
utilized under the following conditions:

• Zone temp is above the active
cooling setpoint

• Zone temp error < 1.5 F above the
active cooling setpoint

Compressor 2 will not be on at the

same time as the reheat solenoid. No
pulse width modulation is used during
dehumidification.

For both single and two-stage cool­ing, the following conditions will cause
the ZN524 to transition out of dehumid­ification mode:

• Relative humidity [ disable setpoint

• Zone temp á 1.5 F

• Unit mode = heating

Note: For both single and two­stage cooling, the occupied cool­ing and occupied heating setpoints
can be the same, which may create
some risk of switching over to
heating mode unless the transition.

D

EFROST

For defrost operation, a sensor is wired
to BIP 1. When a defrost condition is
detected, the compressor(s) are dis­abled, and the unit is placed in the

DEFROST mode.

During DEFROST the compressor(s) are
off, and the fan will continue to operate
as continuous. The unit will remain in
the

DEFROST mode until the sensor

resets. The unit will return to NORMAL
operation after the mode is discontin­ued.

P

RE-HEAT

The Tracer ZN524 controller keeps the
2-position outdoor air damper closed
anytime during the OCCUPIED mode
when the space temperature is 3°F or
more below the heating setpoint.

The damper remains closed indefinitely
during morning pre-heat until the space
temperature is within 2°F of the effec­tive heating setpoint. The unit runs at
full capacity until setpoint is met.

30 CNT-SVX11A-EN

Unit Operation

PRE

-COOL

The Tracer ZN524 controller keeps the
2-position outdoor air damper closed
for up to one hour at every transition
from unoccupied to occupied mode
when the space temperature is 3°F or
more above the cooling setpoint.

The damper remains closed during pre­cool until the space temperature is
within 2°F of the effective cooling set­point. The unit runs at full capacity until
setpoint is met.

Output Overrides

Manual Output Test

Manual output test allows the binary
outputs to be energized in a predefined
sequence. (For more information see,
Manual Output Test, on pages 32-33 for
more information.)

Fan Status

There are two ways to do fan status
monitoring:

1. The status of the fan is reported
based on the state of the binary out
put(s) dedicated to fan control. The
fan status is reported as

ON

whenever the corresponding binary
output is directed on. The fan status is
reported as off when the fan
output is directed

ON.

2. The Tracer ZN524 controller has a
binary input available for a fan status
device (current sensing relay) which
can provide feedback of fan
operation. If the device does not
indicate fan operation after 1 minute
as commanded

ON, a unit shut down

is initiated, and the unit is latched

OFF.

Filter Status/Maintenance Timer

The unit filter status\maintenance timer
is based on the cumulative run hours of
the unit fan. The controller compares
the fan run time against an adjustable
fan run hour limit and recommends
unit maintenance as required.

The Rover service tool is used to edit
the maintenance required setpoint
time. Once the setpoint limit is exceed­ed, the controller generates a mainte­nance required informational diagnos­tic. When the

MAINTENANCE REQUIRED set-

point time is set to zero, the controller
disables this feature.

The Tracer Summit, Tracker or the Rover
service tool are required to clear the

MAINTENANCE REQUIRED

informational
diagnostic. Once the diagnostic is
cleared, the controller resets the fan
run time to zero and begins accumulat­ing fan run hours again.

Note: If at any time the unit loses
power, the timer is reset to zero.

CNT-SVX11A-EN 31

Unit Operation

Figure 16: Simple data sharing application

Figure 17: More complex data sharing application

ZN524

ZN524

ZN524

Master

Comm5 Link

Zone Sensor

Slave

Slave

Slave

B1

Slave

A2

Slave

A1

Master

A

Master

B

Tracer Summit

Zone

Sensor

Zone

Sensor

Zone BZone A

Data Sharing—LonWorks

Tracer ZN524 allows peer-to-peer data
communication through the use of
LonWork’s technology. Data such as
space temperature setpoint, occupancy,
etc. can be shared from a master con­troller to a peer controller over a twist­ed pair of communication wire with or
without the presence of a front end
building management system. (See

Figure 16: “Simple data sharing appli­cation”) This ability allows units to
operate with the same data to prevent
conflicting control.

Data sharing is established through the
use of “bindings”. Bindings are set up
through the Rover service tool.

The Tracer ZN524 controller includes a
network variable for master/slave oper­ation. This variable includes all of the

information required for the slave units
to operate with master controller. (See
Figure 17: “More complex data sharing
application”)

For more information on establishing
bindings, see the Rover service tool
manual. For a complete listing on
shared points see

“Appendix—Data

Lists” on page 47.

32 CNT-SVX11A-EN

Troubleshooting

Important! When viewing the Tracer
ZN524 through the Rover service
tool, it is important that the
version be up-to-date. To help
ensure that your version is the
most recent, contact you local
Trane sales representative or
service center.

WARNING

Live Electrical Components

During installation, testing, servicing
and troubleshooting of this product, it
may be necessary to work with live
electrical components. Have a qualified
licensed electrician or other individual
who has been properly trained in han­dling live electrical components per­form these tasks. Failure to follow all
electrical safety precautions when
exposed to live electrical components
could result in death or serious injury.

Led Operation

Table 15:

Red Service LED

Black Service Push Button

Note: If the Service push button is
held down for more than 15

seconds, the Tracer ZN524 Unit
Controller will uninstall itself from
the ICS communication network
and shut down all unit operation.
This mode is indicated by the red
Service LED flashing once every
second. See the Red Service LED
section. Use Rover service tool to
restore the unit to normal
operation.

The Service
push button,
located at the
bottom center
of the con­troller, can be
used to install
the Tracer
ZN524 Unit
Controller in a
communication
network. Refer
to the Rover
and Tracer Summit product literature
for more information.

Green Status LED

The green LED normally indicates
whether or not the controller is pow­ered on (24 VAC).

Table 16:

Green status LED activity

Yellow Comm LED

The yellow Comm LED blinks at the
rate the controller receives communica­tion. The yellow LED does not blink
when the controller is transmitting
communication data.

Table 17:

Yellow comm LED activity

Manual Output Test

The test sequence verifies output and
end device operation. The manual out­put test can be conducted to verify out­put wiring and actuator operation, with­out using the Rover service tool, by
pressing the test button.

Many service calls are initiated due to
unit diagnostics, so the test sequence
attempts to clear unit diagnostics and
restore normal unit operation prior to
testing the outputs. If the diagnostics
remain after an attempt to clear diag­nostics, the status LED lights in a two­blink pattern, indicating the diagnostic
condition is still present.

See Table 18,
Page 33 for more
details.

Yellow LED Description

activity

LED off Controller is not detecting

continuously. any communication.

(Normal for standalone
applications.)

LED blinks or . The controller detects
flickers communication. (Normal

for communicating
applications, including
data sharing.)

LED on Abnormal condition or
continuously. extremely high traffic on

the link.

Red LED Description

activity

LED is off
continuously
after power is Normal operation.
applied to the
controller.

LED is on
continuously, Someone is pressing
even when the Service push button
power is first or the controller has
applied to the failed.
controller.

Un-install (normal

controller mode). Use
LED flashes Rover service tool to
about once restore the unit to normal
every second. operation. Refer to the

Rover product literature

for more information.

Green LED Description

activity

LED is on Power on
continuously. (normal operation).

LED blinks The controller is in
(1 blink per manual output test mode.
second) No diagnostics present.

The controller is in manual
LED blinks output test mode.
(2 blinks One or more diagnostics
per second). are present.

LED blinks Wink mode
1/4 second on,
1/4 second off
for 10 seconds

Power is off.
LED off Controller failure.

Test button is pressed.

Figure 19:

Blue

test button

Figure 18:

Black service button

CNT-SVX11A-EN 33

Troubleshooting

If a two-blink pattern remains after an
attempt to clear diagnostics, the diag­nostic condition is still present and may
affect the manual output test. The diag­nostic must then be cleared using
another method. (See “Resetting
Diagnostics” on page 35 for more
information.)

Test Procedure

The procedure for testing is:

1. Press and hold the Test button for at
least two seconds, then release the
button to start the test mode.

2. When manual output test mode
begins, the controller turns off all out
puts and calibrates end devices
closed.

3. Press the Test button once to advance
through each step of the test
sequence.

Note: To help ensure accurate
testing do not press the test
button more than once per second.

Alternatively, the manual output test
can be controlled over the communica­tions network by using Rover. When
conducting the manual output test via
communications network, the sequence
must start with Step 1 (

OFF), as shown

in Table 18.

Step Fan Reversing Elec. Heat/ Compressor Compressor Isolation Isolation Water-side Outside Air Generic

Valve Reheat 1 2 Valve 1 Valve 2 Economizer Damper

BO1 BO2 BO3 BO4 BO5 BO6 BO7 BO8 BO9 BO10

1. Off

1

Off Off Off Off Off Off Off Off Off Off

2. Fan

2

On

3. Isolation On On
Valve 1

4. Waterside On On On

Economizer

5. Isolation On On On
Valve 1 & 2

6. Reversing On On On On
Valve

7. 1st Stage On On On On On

Cool

8. 1st & 2nd On On On On On On

Stage Cool

9. Heat Mode:

See Table Below

10.

Compressor

3

On On On

11. 1st Stage On On On On

Heat

12. 2nd Stage On On On On On

Heat

13. Outside

4

On On

Air Damp.

14. Generic

5

On On

Output

1. Upon entering manual output test mode, the controller turns off all fan outputs and drives all dampers and valves closed (if required).

2. At the beginning of Step 2, the controller attempts to clear all diagnostics.

3. This stage helps avoid an abrupt transition from cooling to heating by turning off the compressors prior to changing the reversing valve
state.

4. Binary output 9 (BOP9) will be controlled during this step regardless of its configuration.

5. After the generic output setup, the test sequence performs the exit step. This initiates a reset and attempts to return the controller to
normal operation.

9. Hot Gas On On On On On On

9. No Heat/ On On On On

Boilerless

9. Concurrent On On On On On On

Heat Type

Table 18: Test sequence

34 CNT-SVX11A-EN

Troubleshooting

Diagnostics

Fan Failure

A “Low Air Flow—Fan Failure” diagnos­tic is generated when a fan status
device is present and fails to close after
1 minute of unit start-up or when it
opens for more than 1 minute during
normal unit operation.

Space Temperature Failure

If the Tracer ZN524 has validated a
space temperature input and then the
input becomes invalid, a space temper­ature failure diagnostic occurs.

Entering Water Temperature Failure

If the Tracer ZN524 has validated an
entering water temperature input and
then the input becomes invalid, an
entering water temperature failure diag­nostic occurs.

Discharge Air Temperature Limit

When the discharge air exceeds the low
limit setpoint and the unit can not cor­rect it by altering capacity, a “Discharge
Air Temp Limit” diagnostic is generated.

Outdoor Air Temperature Failure

If the Tracer ZN524 has validated an
outdoor air temperature input and then
the input becomes invalid, an outdoor
air temperature failure diagnostic
occurs.

Humidity Input Failure

If the Tracer ZN524 has validated a rela­tive humidity input and then the input
becomes invalid, a humidity input fail­ure diagnostic occurs.

CO

2

Sensor Failure

If the Tracer ZN524 has validated a CO

2

input and then the input becomes
invalid, a CO2input failure diagnostic
occurs.

Generic AIP Failure

If the Tracer ZN524 has validated a
generic analog input and then the input
becomes invalid, a generic analog input
failure diagnostic occurs.

Defrosting-Compressor Lockout

The defrost stat used with Tracer ZN524
on DX units is wired in series with the
condensing unit. When it opens to indi­cate a frost condition, the Tracer ZN524
senses the open circuit and de-ener­gizes the compressor output. A defrost­ing diagnostic is generated at this
point.

Maintenance Required

Note: If power to the unit is cycled
or discontinued for any reason, all
maintenance timers are automati­cally reset.

The “Maintenance Required” diagnostic
is generated when the fan run-time
exceeds the configurable limit. This
diagnostic is useful for filter change
notification.

Local Fan Mode Failure

If the hardwired fan mode input to the
Tracer ZN524 controller is present and
then becomes invalid, a local fan mode
failure diagnostic is generated.

Local Setpoint Failure

If the hardwired setpoint input to the
Tracer ZN524 controller is present and
then becomes invalid, a local setpoint
failure diagnostic is generated.

Generic Temperature Failure

If the Tracer ZN524 has validated a
generic temperature input and then the
input becomes invalid, a generic tem­perature input failure diagnostic occurs.

Invalid Unit Configuration

If the Tracer ZN524 has been configured
improperly or loses its configuration,
an invalid unit configuration diagnostic
is generated. The unit must be re-con­figured with a valid configuration to
correct this problem.

CNT-SVX11A-EN 35

Troubleshooting

Diagnostic Unit Response Latching/ Reset

non-latching

Fan—off Auto reset once within 24 hrs.

Valves—closed If safety generates a diagnostic
High/Low Pressure Compressor - off Latching more than once a communicated
Cutout

2

or manual reset will be
necessary

Fan—off
Low Air Flow/ Valves—closed
Fan Failure

2

Compressors—off Latching Communicated or manual reset

Space Fan—off

Temperature Valves—closed

Failure

2,3

Compressors—off Non-latching Communicated or manual reset

Entering Fan—enabled
Water Temperature Boilerless control—disabled
Failure

2,3

Waterside Economizer—enabled Non-latching Communicated or manual reset

Discharge Air Fan—on Auto reset once within 24hrs.

Temperature Compressor—disable If safety generates a diagnostic

Limit Waterside Economizer—enabled Non-Latching more than once a communicated

or manual reset will be
necessary.

Discharge Fan—enable
Air Temperature Failure

2,3

Compressors—enabled Non-latching Communicated or manual reset

Outdoor Air Fan—enable

Temperature Compressor—enable Non-latching Communicated or manual reset

Failure

2,3

Table 19: Tracer ZN524 Unit Controller diagnostics

1: The generic binary output (TB4-1, TB4-2) state is unaffected by all unit diagnostics.
2: During manual output test, these diagnostics make the green status LED flash in a two-blink pattern. For more information see, Manual
Output Test, on page 32.
3: These diagnostics are non-latching and automatically reset when the input is present and valid.

36 CNT-SVX11A-EN

Troubleshooting

Diagnostic Unit Response Latching/ Reset

non-latching

Fan—enabled

Valves—enabled
Humidity Input Failure

3

Compressor—enabled Non-latching Communicated or manual reset

Reheat—disabled

CO2 Sensor Fan—enabled
Failure

3

Valves—enabled Non-latching Communicated or manual reset

Compressor—enabled

Generic
AIP No Unit Reaction Non-latching Communicated or manual reset
Failure

3

Maintenance Fan—enabled
Required Valves—enabled Non-latching Communicated or manual reset

Compressor—enabled

Local Fan—enabled
Fan Mode Valves—enabled Non-latching Communicated or manual reset
Failure

3

Compressor—enabled

Local Fan—enabled
Setpoint Valves—enabled Non-latching Communicated or manual reset
Failure

3

Outdoor air damper—enabled

Invalid Fan—disabled
Unit Valves—disabled Latching Communicated or manual reset
Configuration

2

Compressor—disabled

Fans—enabled
Normal Valves—enabled Non-latching N/A

Compressor—enabled

Table 19: Tracer ZN524 Unit Controller diagnostics - continued

1: The generic binary output (TB4-1, TB4-2) state is unaffected by all unit diagnostics.
2: During manual output test, these diagnostics make the green status LED flash in a two-blink pattern. For more information see, Manual
Output Test, on page 32.
3: These diagnostics are non-latching and automatically reset when the input is present and valid.

CNT-SVX11A-EN 37

Troubleshooting

Translating Multiple
Diagnostics

The controller senses and records each
diagnostic independently of other diag­nostics. It is possible to have multiple
diagnostics present simultaneously. The
diagnostics are reported in the order
they occur.

Resetting Diagnostics

There are many ways to reset unit diag­nostics:

• Automatically by the controller

• By initiating a manual output test at
the controller

• By cycling power to the controller

• By using a building automation
system

• By using the Rover service tool

• By cycling the fan switch from off to

ON or AUTO

High/Low Pressure Cutout

The Tracer™ ZN524 Unit Controller
includes an automatic diagnostic reset
function. This function attempts to auto­matically recover a unit when the
High/Low Pressure Cutout diagnostic
occurs. When this diagnostic occurs,
the controller responds as defined in
Table 19: Tracer™ ZN524 Unit Controller
diagnostics.

After the controller detects the
High/Low Pressure Cutout diagnostic,
the unit waits 30 minutes before invok­ing the automatic diagnostic reset func­tion. The automatic diagnostic reset
function clears the High/Low Pressure
Cutout diagnostic and attempts to
restore the controller to normal opera­tion. The controller resumes normal
operation until another diagnostic
occurs.

If a High/Low Pressure Cutout diagnos­tic reoccurs within 24 hours after an
automatic diagnostic reset, you must
manually reset the diagnostic. See
other possible methods for resetting
diagnostics in this section.

Manual output test

The test button on the controller may
be used either during installation to
verify proper end device operation or
during troubleshooting.

When the Test button is pressed, the
controller exercises all outputs in a pre­defined sequence. The first and last
steps of the sequence reset the con­troller diagnostics. (See “Manual
Output Test” on page 32 for more infor­mation.)

Cycling power

When turned-off, the controller's 24
VAC power, and power is reapplied, the
unit cycles through a power-up
sequence and clears all timers.
By default, the controller attempts to
reset all diagnostics at power-up.

Diagnostics present at power-up and
those that occur after power-up are
handled according to the defined unit
diagnostics sequences (For more infor­mation see,Table 19).

Building automation system

Some building automation systems
(i.e., Tracer Summit, Tracker or Tracer
Loop Controller building automation
system) can reset diagnostics in the
Tracer ZN524 unit controller. For more
complete information, refer to the prod­uct literature for the building automa­tion system.

Rover service tool

Rover service tool can reset diagnostics
in the Tracer ZN524 unit controller. For
more complete information, refer to the
Rover Installation, Operation, and
Programming manual.

Diagnostic reset

Any device that can communicate the
network variable nviRequest (enumera­tion “clear_alarm”) can reset diagnos­tics in the Tracer ZN524 unit controller.
The controller also attempts to reset
diagnostics whenever power is cycled.

Cycling the fan switch

If the user cycles the fan speed switch
from off to

ON or AUTO, the controller

resets all diagnostics. Diagnostics may
recur immediately if the problem still
exists.

38 CNT-SVX11A-EN

Troubleshooting

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the fan contactor must be present and correct

for normal fan operation

No power to the controller If the controller does not have power, the unit fan does not operate. For the Tracer ZN524 Unit

Controller to operate normally, it must have an input voltage of 24 VAC. When the green LED is off
continuously, the controller does not have sufficient power or has failed.

Unit configuration The controller must be properly configured based on the actual installed end devices and application.

When the unit configuration does not match the actual end devices, the fans may not work correctly.

Random-start observed After power-up, the controller always observes a random-start from 5 to 30 seconds. The controller

remains off until the random-start time expires.

Power-up control wait When power-up control wait is enabled (non-zero time), the controller remains off until one of two

conditions occurs:

1. The controller exits power-up control wait once it receives communicated information.

2. The controller exits power-up control wait once the power-up control wait time expires.

Diagnostic present A specific list of diagnostics affects fan operation. For more information see, Table 19: Tracer ZN524

Unit Controller diagnostics, page 33.

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the unit fan may not
be on. For more information see, Manual Output Test, on page 32 for more information.)

Fan mode off When a local fan mode switch (provided on the Trane zone sensor) determines the fan operation, the off

position controls the unit off.

Requested mode off You can communicate a desired operating mode (such as off, heat, and cool) to the controller. When off

is communicated to the controller, the unit controls the fan off. There is no heating or cooling.

Unoccupied operation When the controller is in the unoccupied mode, the fan is cycled.

Cycling fan operation/continuous The controller can cycle fan with unit capacity. If no capacity is present, the fan will be de-energized

Table 19:

Fan Outputs do not energize

Fans

CNT-SVX11A-EN 39

Troubleshooting

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the valve(s) must be present and correct for normal

valve operation.

Random-start observed After power-up, the controller always observes a random-start from 5 to 30 seconds. The controller

remains off until the random-start time expires.

Power-up control wait When power-up control wait is enabled (non-zero time), the controller remains off until one of two

conditions occurs:

1. The controller exits power-up control wait once it receives communicated information.

2. The controller exits power-up control wait once the power-up control wait time expires.

Diagnostic present A specific list of diagnostic affects valve operation. For more information see, Table 19 for more

information

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the valve(s) may not
be open. For more information see, Manual Output Test, on page 32 for more information.)

Fan mode off When a local fan mode switch (provided on the Trane zone sensor) determines the fan operation, the off

position controls the unit off and valves to close.

Requested mode off You can communicate a desired operating mode (such as off, heat, and cool) to the controller. When off

is communicated to the controller, the unit controls the fan off. There is no heating or cooling (valves
are closed).

Sampling logic The controller includes entering water temperature sampling logic which is automatically invoked

when a waterside economizer or boilerless control is present. For more information see, Entering Water
Temperature Sampling, on Sampling logic page 26 for more information.)

Table 20:

Isolation valves stay closed

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the valve(s) must be present and correct for normal

valve operation.

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the valve(s) may be
open. For more information see, Manual Output Test, on page 32 for more information.)

Sampling logic The controller includes entering water temperature sampling logic which automatically invoked during

when waterside economizer or boilerless control is present. For more information see, Entering Water
Temperature Sampling, on page 26 for more information.)

Normal operation The controller opens and closes the valves to meet the unit capacity requirements.

Table 21:

Isolation valves stay open

Valve s

40 CNT-SVX11A-EN

Troubleshooting

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the end devices must be present and correct for normal

operation.

Unit configuration The controller must be properly configured based on the actual installed end devices and application.

When the unit configuration does not match the actual end devices, the unit may not work correctly.

Diagnostic present A specific list of diagnostics affect compressor and electric heat operation. For more information see,

Table 19, page 35 for more information.

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the DX or electric
outputs may be off. For more information see, Manual Output Test, on page 32 for more information.)

Normal operation The controller energizes the outputs only as needed to meet the unit capacity requirements.

Table 22:

Compressor or electric heat output(s) do not energize

DX/Electric Heat

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the outdoor air damper must be present and correct for

normal damper operation.

Unit configuration The controller must be properly configured based on the actual installed end devices and application.

When the unit configuration does not match the actual end devices, the damper may not work correctly.

Random-start observed After power-up, the controller always observes a random-start from 5 to 30 seconds. The controller

remains off until the random-start time expires.

Power-up control wait When power-up control wait is enabled (non-zero time), the controller remains off until one of two

conditions occurs:

1. The controller exits power-up control wait once it receives communicated information.

2. The controller exits power-up control wait once the power-up control wait time expires.

Diagnostic present A specific list of diagnostics affects outdoor air operation. For more information see, Table 19

on page 35 for more information.)

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the unit damper
may not be open. For more information see, Manual Output Test, on page 32 for more information.)

Fan mode off When a local fan mode switch (provided on the Trane zone sensor) determines the fan operation, the off

position controls the unit off and damper to close.

Table 23:

Outside air damper stays closed

Outside Air Damper

CNT-SVX11A-EN 41

Troubleshooting

Probable cause Possible Explanation

Requested mode off You can communicate a desired operating mode (such as off, heat, and cool) to the controller. When off

is communicated to the controller, the unit controls the fan off. There is no heating or cooling (valves
are closed).

Unoccupied mode When the controller is in the unoccupied mode, the outdoor air damper remains closed.

Warm up and cool-down The controller includes both a morning warm up and cool-down sequence to keep the outdoor air

damper closed during the transition from unoccupied to occupied. This is an attempt to bring the space
under control as quickly as possible.

The controller opens and closes the outdoor air damper based on the controller's occupancy mode and

Normal operation fan operation. Normally, the outdoor air damper is open during occupied, occupied standby, and

occupied bypass mode when the fan is running and closed during unoccupied mode.

Table 23:

Outdoor air damper stays closed - continued

Probable cause Possible Explanation

Unit wiring The wiring between the controller outputs and the outdoor air damper must be present and correct for

normal damper operation.

Unit configuration The controller must be properly configured based on the actual installed end devices and application.

When the unit configuration does not match the actual end devices, the damper may not work correctly.

Manual output test The controller includes a manual output test sequence you can use to verify output operation and

associated output wiring. However, based on the current step in the test sequence, the unit damper
may be open. For more information see, Manual Output Test, on page 32 for more information.)

The controller opens and closes the outdoor air damper based on the controller's occupancy mode and
fan operation. Normally, the outdoor air damper is open during occupied, occupied standby, and

Normal operation occupied bypass mode when the fan is running and closed during unoccupied mode unless the

controller is economizing.

Table 24:

Outdoor air damper stays open

Probable cause Possible Explanation

Sensor reading too low

Unit economizing without much cooling capacity or unit stops DX heating early and switches to boiler­less electric heat.

Sensor reading too high

Unit not utilizing economizer capacity when possible or DX heating stays on longer than possible for
boilerless electric heat unit.

Reading out of range Boilerless electric heat or waterside economizer disabled.

Table 25:

Entering Water Temperature sensor read-out error

42 CNT-SVX11A-EN

Replacing Circuit Boards

Tracer ZN524 Unit Controller
Replacement

WARNING
Hazardous Voltage!

Disconnect all electric power, including
remote disconnects before servicing.
Follow proper lockout/tagout proce­dures to ensure the power can not be
inadvertently energized. Failure to dis­connect power before servicing could
result in death or serious injury.

1. Disconnect power or disable the

circuit breaker to unit.

2. Remove bad or questionable

Tracer ZN524 controller circuit
board.

3. Install controller in the unit with

the heat-sink placement at the
top of the control box.

4. Connect the power to the circuit

board ONLY.

5. Connect Rover and properly

configure the controller, unless a
previously configured board is
purchased.

6. Power down.

7. Connect the remaining input and
output wiring to the controller and
comm wire.

8. Reapply power.

9. Complete sequence 7 and 8 above
in the installation section of this
manual.

10. Record NID numbers and unit
location

11. Refer to BAS manual for
instructions on how to configure
the new ZN524 into BAS system.

CNT-SVX11A-EN 43

Appendix

Resistance (VV) Setpoint (°F)

889.4 50

733.6 58

577.9 66
500 70

422.1 74

344.2 78

266.4 82

188.5 86

110.6 90

Hardwired Setpoint Adjustment

Table 26: Hardwired setpoint adjustment

Fan Switch Resistance Values

Table 27: Resistance Values

Resistance (VV) Switch Position

16,300 High
10,700 Low

2,320 Auto
4,870 Off

Resistance (VV) Temperature

87.5kV 0°F

74.6kV 5°F

63.8kV 10

°F

54.6kV 15°F

46.9kV 20°F

40.4kV 25

°F

34.8kV 30°F

30.2kV 35°F

26.2kV 40

°F

22.8kV 45

°F

20.0kV 50°F

17.5kV 55

°F

15.3kV 60

°F

13.5kV 65°F

11.9kV 70

°F

10.5kV 75°F

Resistance (VV) Temperature

10.0kV 77°F

9.3kV 80°F

8.2kV 85°F

7.3kV 90°F

6.5kV 95°F

5.8kV 100°F

5.2kV 105

°F

4.7kV 110 °F

4.2kV 11 5 °F

3.8kV 120

°F

3.4kV 125

°F

3.1kV 130°F

2.8kV 135

°F

2.5kV 140

°F

2.3kV 145°F

2.1kV 150°F

Hardwired Thermistor Values

Table 28: Hardwired 10kV thermistor values

44 CNT-SVX11A-EN

Appendix - Binary
Configuration

Binary input Function Configuration Description

or output

BI 1 Low temp detection Normally closed Closed: BIP 1 is Normal (no diagnostic)

Open: BIP 1 is Active (diagnostic)

BI 2 Condensate overflow Normally closed Closed: BIP 2 is Normal (no diagnostic)

Open: BIP 2 is Active (diagnostic)

BI 3 Occupancy/Generic Normally closed Closed: BIP 3 is Normal (Occupied)

Open: BIP 3 is Active (Unoccupied)

1

Normally open Open: BIP 3 is Normal (Occupied)

Closed: BIP 3 is Active (Unoccupied)

1

BI 4 Fan status

2

Normally open When the controller commands the fan on and the binary input

remains open for one minute, BIP is normal (diagnostic).
When the controller commands the fan on and the binary input
closes, BIP is active (no diagnostic).

J1-1 Fan Normally open De-energized: Fan off

Energized: Fan on

J1-2 RV Normally open De-energized: Heat

Energized: Cool

J1-3 Electric Heat/ Normally open De-energized: Off

Reheat Energized: Electric Heat/Reheat active

TB4-1 and TB4-2 Generic binary output Normally open De-energized: Output off (de-energized)

Energized: Output on (energized)

1. The occupancy input applications vary for standalone and communicated instances. For more information, see Occupancy arbitration
tables in the Appendix.

2. The fan status device is normally closed during normal fan operation. When the fan is off either from a fan failure or the controller com­manding the fan off, the binary input device opens.

Binary Configuration

Table 29: Binary configuration details

CNT-SVX11A-EN 45

Appendix - Unit
Operation

Unit Operation Based On The Effective H

EAT/C

OOL Output

Table 30: Unit operation based on H

EAT

/C

OOL

ouput

Application Heat/cool mode input Effective heat/ cool Unit Operation
mode input

(nviHeatCool) mode output

(nviApplicMode) (nvoHeatCool)

Auto Determined by controller Fan—Enabled

Heating—Enabled
Cooling—Enabled
Damper—Enabled

Heat Heating Fan—Enabled

Heating—Enabled
Cooling—Disabled
Damper—Enabled

Morning warm up Pre-heat Fan—Enabled

Heating—Enabled
Cooling—Disabled
Damper—Disabled

Cooling Cooling Fan—Enabled

Heating—Disabled

1

Cooling—Enabled
Damper—Enabled

Auto Pre-cool Pre-cool Fan—Enabled

Heating—Disabled

1

Cooling—Enabled
Damper—Disabled

Off Off Fan—Disabled

Heating—Disabled
Cooling—Disabled
Damper—Disabled

Test Test Fan—Enabled

Heating—Enabled
Cooling—Enabled
Damper—Enabled

Fan only Fan only Fan—Enabled

Heating—Disabled
Cooling—Disabled
Damper—Enabled

Not present Determined by controller Fan—Enabled

Heating—Enabled
Cooling—Enabled
Damper—Enabled

Heat Any state Heating Fan—Enabled

Heating—Enabled
Cooling—Disabled
Damper—Enabled

Morning warm up Any state Pre-heat Fan—Enabled

Heating—Enabled
Cooling—Disabled
Damper—Disabled

46 CNT-SVX11A-EN

Appendix - Unit
Operation

Application Heat/cool mode input Effective heat/ cool Unit Operation
mode input

(nviHeatCool) mode output

(nviApplicMode) (nvoHeatCool)

Cool Any state Cool Fan—Enabled

Heating—Disabled
Cooling—Enabled
Damper—Enabled

Pre-cool Any state Pre-cool Fan—Enabled

Heating—Disabled
Cooling—Enabled
Damper—Disabled

Off Any state Off Fan—Disabled

Heating—Disabled
Cooling—Disabled
Damper—Disabled

Test Any state Determined by controller Fan—Enabled

Heating—Enabled
Cooling—Enabled
Damper—Enabled

Fan only Any state Fan only Fan—Enabled

Heating—Disabled
Cooling—Disabled
Damper—Enabled

Note: Night purge, Emergency heat, and Nul modes are not supported by the Tracer ZN524 Unit Controller. If one of these
modes is received by the controller, it is interpreted as Auto.

Table 30: Unit operation based on H

EAT/COOL

ouput - continued

CNT-SVX11A-EN 47

Appendix ­Data Lists

Table 31: Input/Output listing

Data Lists

Table 31 provides an input/output list­ing for the Tracer ZN524 unit controller.
The content of the lists conforms to
both the LonMark Space Comfort
Controller Functional Profile and the
LonMark node object

Table 32: Configuration properties

Configuration property SNVT type SCPT reference Description

nciSndHrtBt

1

SNVT_time_sec SCPTmaxSendTime (49) Send heartbeat

nciSetpoints

1

SNVT_temp_setpt SCPTsetPnts (60) Occupancy temperature set

points

nciUnitType

1

SNVT_hvac_type SCPThvacUnitType (169) Unit type
nciMinOutTm SNVT_time_sec SCPTminSendTime (52) Minimum send time
nciRcvHrtBt SNVT_time_sec SCPTmaxRcvTime (48) Receive heartbeat
nciLocation SNVT_str_asc SCPTlocation (17) Location label
nciBypassTime SNVT_time_min SCPTbypassTime (34) Local bypass time
nciSpaceRHSetpt SNVT_lev_percent SCPThumSetPT(36) Space RH Setpoint

Input SNVT type Output SNVT type

nviRequest SNVT_obj_request nvoStatus SNVT_obj_status

nviSpaceTemp

1

SNVT_temp_p nvoFileDirectory SNVT_address

nviSetpoint SNVT_temp_p nvoSpaceTemp

1

SNVT_temp_p

nviSetptOffset SNVT_temp_p nvoUnitStatus

1

SNVT_hvac_status

nviOccSchedule SNVT_tod_event nvoEffectSetpt SNVT_temp_p

nviOccManCmd SNVT_occupancy nvoEffectOccup SNVT_occupancy

nviOccSensor SNVT_occupancy nvoHeatCool SNVT_hvac_mode

nviApplicMode SNVT_hvac_mode nvoSetpoint SNVT_temp_p

nviHeatCool SNVT_hvac_mode nvoDischAirTemp SNVT_temp_p

nviFanSpeedCmd SNVT_switch nvoLoadAbsK SNVT_power_kilo

nviComprEnable SNVT_switch nvoTerminalLoad SNVT_lev_percent

nviAuxHeatEnable SNVT_switch nvoSpaceRH SNVT_lev_percent

nviEconEnable SVNT_switch nvoOutdoorTemp SNVT_temp_p

nviEmergOverride SNVT_hvac_emerg nvoSpaceCO2 SNVT_ppm

nviSourceTemp SNVT_temp_p nvoEnterWaterTemp SNVT_temp_p

nviSpaceRH SNVT_lev_percent nvoLeaveWaterTemp SNVT_temp_p

nviOutdoorTemp SNVT_temp_p

1. Required points under Space Comfort Controller profile. All other points are optional.

48 CNT-SVX11A-EN

Location Identifier

CNT-SVX11A-EN 49

Location Identifier

50 CNT-SVX11A-EN

Location Identifier

CNT-SVX11A-EN 51

Location Identifier

Literature Order Number CNT-SVX11A-EN

Date August 2003

Supercedes New

Stocking Location Inland

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reserves the right to change design and specifications without notice.

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