Trane Tracer ZN521 Owner's manual

SAFETY WARNING
Only qualified personnel should install and service the equipment. The installation, starting up, and servicing
of heating, ventilating, and air-conditioning equipment can be hazardous and requires specific knowledge and
training. Improperly installed, adjusted or altered equipment by an unqualified person could result in death or
serious injury. When working on the equipment, observe all precautions in the literature and on the tags,
stickers, and labels that are attached to the equipment.
November 2010 CNT-SVX07D-EN
Installation and
Operation
Tracer™ZN521 Zone Controller

2Doc Number (Variable)
Copyright
© 2010 Trane All rights reserved
This document and the information in it are the property of Trane and may not be used
or reproduced in whole or in part, without the written permission of Trane. Trane reserves
the right to revise this publication at any time and to make changes to its content without
obligation to notify any person of such revision or change.
Trademarks
Trane and its logo are trademarks of Trane in the United States and other countries. All
trademarks referenced in this document are the trademarks of their respective owners.
Warnings, Cautions, and Notices
Warnings, cautions, and notices are provided in appropriate places throughout this
document:
WARNING: Indicates a potentially hazardous situation which, if not avoided,
could result in death or serious injury.
CAUTION: Indicates a potentially hazardous situation which, if not avoided,
could result in minor or moderate injury. It could also be used to alert against
unsafe practices.
NOTICE:Indicates a situation that could result in equipment or property-
damage-only accidents.

Table of Contents
CNT-SVX07D-EN 3
Overview and specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Storage environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Clearances . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Agency listing/compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Additional components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
General wiring information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Input/output terminal wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
AC power wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Communication-link wiring and addressing . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Mounting the controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Location recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Operating environment requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Mounting recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Input/output functions and wiring for typical applications . . . . . . . . . . . . . . . . . 13
Binary inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
BI1: Low-coil-temperature detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
BI2: Condensate overflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
BI3: Occupancy or generic binary input . . . . . . . . . . . . . . . . . . . . . . . . . . 14
BI4: Fan status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Analog inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
GND: Ground terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
ZN: Zone temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
SET: Local setpoint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
FAN: Fan mode input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
AI1: Entering water temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
AI2: Discharge air temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
AI3: Outdoor air temperature or generic temperature . . . . . . . . . . . . . . . 16
AI4: Universal 4–20 mA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Binary outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Generic binary output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Overriding binary outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Wiring requirements and options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Sequence of operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Power-up sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Random start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Occupancy modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Occupied mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4CNT-SVX07D-EN
Unoccupied mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Occupied standby mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Occupied bypass mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Timed override control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Zone temperature control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Cascade zone control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Simplified zone control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Discharge air tempering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Morning warm-up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Morning cool-down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Heating or cooling mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Entering water temperature sampling function . . . . . . . . . . . . . . . . . . . . . . . 35
Fan operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Exhaust control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Valve operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Modulating valve operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Modulating valve calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Two-position valve operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Isolation-valve operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Two-pipe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Four-pipe operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Modulating outdoor/return air dampers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
ASHRAE Cycle 1 conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
ASHRAE Cycle 2 conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Economizing (free cooling) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Two-position control of a modulating outdoor air damper . . . . . . . . . . . . . 39
Face-and-bypass damper operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Face-and-bypass, isolation-valve operation . . . . . . . . . . . . . . . . . . . . . . . 39
DX cooling operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Electric heat operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Baseboard heat operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Dehumidification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Peer-to-peer communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Unit protection strategies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Smart reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Low-coil-temperature protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Condensate overflow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Fan status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Fan off delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Filter-maintenance timer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Freeze avoidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Freeze protection (discharge air temperature low limit) . . . . . . . . . . . . . 42

CNT-SVX07D-EN 5
Status indicators for operation and communication . . . . . . . . . . . . . . . . . . . . . . 43
Test button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Manual output test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Service pin button . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Interpreting LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Types of diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Table of diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

6CNT-SVX07D-EN
Overview and specifications
This guide provides installation and configuration information for the Tracer ZN521 zone controller,
as well as a description of its operations. The overview includes a product description,
specifications, and descriptions of ancillary products that may be necessary.
Product description
The Tracer ZN521 is an application-specific controller that provides direct-digital zone temperature
control. The controller can operate as a stand-alone device or as part of a building automation
system (BAS). Communication between the controller and a BAS occurs by means of a LonTalk
communication link, which complies with the LonTalk protocol.
The Tracer ZN521 supports the following equipment:
• Fan coils
• Unit ventilators
• Blower coils
The Tracer ZN521 can be configured to control:
• Tri-state modulating or two-position valves
• Tri-state modulating dampers:
outdoor/return air, and face-and-bypass
• DX cooling (single stage)
• Electric heat (two stages)
It is designed to be field-installed and is sent from the factory unconfigured. Use the PC-based
Rover service tool to configure the controller for specific applications.
Note: For information about using the Rover service tool, see the current version of the Rover
Installation/Operation/Programming guide (EMTX-SVX01).
Storage environment
If a Tracer ZN521 zone controller is to be stored for a substantial amount of time, store it in an indoor
environment that meets the following requirements:
• Temperature: –40° to 185°F (–40° to 85°C)
• Relative humidity: 5–95%, noncondensing
Dimensions
Plastic-cover model dimensions
For complete dimensional drawing, see Figure 1 on page 7.
• Height: 5.375 in. (137 mm)
• Width: 6.875 in. (175 mm)
• Depth: 2 in. (51 mm)
Metal-cover model dimensions
For complete dimensional drawing, see Figure 2 on page 8.
• Height: 9.0 in (25 mm)
• Width: 10.37in. (263 mm)
• Depth: 2.25 in. (58 mm)

CNT-SVX07D-EN 7
Overview and specifications
Clearances
Plastic-cover model (see Figure 1 on page 7)
• Front: 4.0 in. (102 mm)
• Each side: 1.0 in. (25 mm)
• Top and bottom: 4.0 in. (102 mm)
Metal-cover model (see Figure 2 on page 8)
• Front: 24.0 in. (610 mm)
• Each side: 2.0 in. (51 mm)
• Top and bottom: 1.0 in. (25 mm)
Figure 1. Plastic-cover model dimensions and clearances
4 in.
(102 mm)
5.625 in (143 mm)
1 in
(25 mm)
6.875 in
(175 mm)
1 in
(25 mm)
4 in
(102 mm)
4 in
(102 mm)
6.31
(160 mm)
2 in. (51 mm)
5.625 in.
(143 mm)

8CNT-SVX07D-EN
Overview and specifications
Figure 2. Metal-cover model dimensions and clearances
Agency listing/compliance
CE—Immunity: EN 50082-1:1997; EN 50082-2:1995
CE—Emissions: EN 50081-1:1992 (CISPR 22) Class B
UL and C-UL 916 listed: Energy management system
UL 94-5V (UL flammability rating for plenum use)
FCC Part 15, Class A
ASHRAE Cycle 1 & Cycle 2 control sequences
Additional components
The Tracer ZN521 zone controller requires the use of additional components for monitoring and
proper control of the associated equipment. The use of specific components depends on the
application. These components are not included with the Tracer ZN521 zone controller.
Power transformer
Use a UL-listed Class 2 power transformer supplying a nominal 24 Vac (19–30 Vac) to power both
the Tracer ZN521 zone controller (14 VA) and its associated output devices, including relays and
actuators, to a maximum of 12 VA per output utilized.
Water, duct, and outdoor-air temperature sensors
Temperature sensors must be Trane 10 kΩ(at 25°C) thermistors. Entering water and discharge air
inputs may use a sealed temperature sensor (part number 4190 1100).
9 in.
(229 mm)
2.25in.
(58 mm)
1 in.
(25 mm)
1 in.
(25 mm)
9 in.
(229 mm)
24 in.
(610 mm)
2 in.
(51 mm)
Clearances
Dimensions
2 in.
(51 mm)
1 in.
(25 mm)
7 in.
(178 mm)
1.875 in.
(48 mm)
0.28 in.
(7 mm)
6.5 in.
(165 mm)
10.25 in.
(260 mm)
width without cover
10.37 in.
(263 mm)
width with cover

CNT-SVX07D-EN 9
Overview and specifications
Binary input switching devices
Occupancy, condensate overflow, low-coil-temperature, and fan status inputs accept switching
devices that may have normally open or normally closed dry contacts.
Output devices
Output devices connected to the Tracer ZN521 binary outputs cannot exceed 12 VA (0.5 A) current
draw at 24 Vac.
Zone temperature sensors
Ta b l e 1 shows the Trane zone temperature sensors that are supported by the Tracer ZN521 zone
controller.
Valve actuators
Valve actuators cannot exceed 12 VA draw at 24 Vac. For two-position valves, use actuators with
on/off action, and with a spring action that returns the valve to normally open or closed (dependent
on the desired default position). For modulating valve control, use tri-state modulating actuators
with or without a spring return, as required by the application.
Damper actuators
Damper actuators cannot exceed 12 VA draw at 24 Vac. For control of outdoor/return air dampers,
use tri-state modulating actuators that incorporate a spring return.
Zone humidity sensor
For measurement of relative humidity (RH), the Tracer ZN521 requires a zone humidity sensor with
a 4–20 mA output, where 4 mA is 0% RH and 20 mA is 100% RH. The controller provides 20 Vdc to
power the zone humidity sensor.
CO2sensor
For CO2measurement, the Tracer ZN521 requires a CO2sensor with a 4–20 mA output, where 4 mA
= 0 ppm and 20 mA = 2000 ppm.
Table 1. Tracer zone temperature sensor options
BAS
order
number Use
Fan Zone
Timed
override
buttons
Comm
jack
High Med Low Auto Off
Setpoint
thumb-
wheel Temperature
sensor On Cancel
4190 1087 Any x
4190 1088 Any x x x x
4190 1090 Any x x x x x
4190 1094 Any x x x
4190 1095 Unit
ventilator x x x x x x x x
4190 1115 Fan coil x x x x x x x x x x
4190 1116 Unit
ventilator x x x x x x x x x
4190 1117 Any x x x x x x x

10 CNT-SVX07D-EN
General wiring information
This chapter provides specifications and general information about wiring the Tracer ZN521 zone
controller. The controller requires wiring for:
• Input/output terminals
• AC power to the controller
• Communication-link wiring, if the controller is to communicate with a building automation
system (BAS)
Input/output terminal wiring
All input/output terminal wiring for the Tracer ZN521 zone controller is application specific and
dependant on the configuration of the controller. Input/output terminal wiring must meet the
following requirements:
• All wiring must comply with the National Electrical Code and local codes.
• Use only 18 AWG, twisted-pair wire with stranded, tinned-copper conductors. (Shielded wire
is recommended.)
• Binary input and output wiring must not exceed 1000 ft (300 m).
• Analog input wiring must not exceed 300 ft (100 m).
• Do not run input/output wires in the same wire bundle with any ac power wires.
For application-specific wiring information and diagrams, see “Input/output functions and wiring
for typical applications,” p. 13
AC power wiring
WARNING
Hazardous Voltage!
Before making line voltage electrical connections, lock open the supply-power disconnect
switch. Failure to do so may cause death or serious injury.
CAUTION
Proper Grounding Required!
Make sure that the 24 Vac transformer is properly grounded. Failure to do so may result in
personal injury or equipment damage.
Notice:
Avoid damage to the controller!
Complete input/output wiring before applying power to the Tracer ZN521 zone controller.
Failure to do so may cause damage to the controller or power transformer due to inadvertent
connections to power circuits.
Important: Do not share 24 Vac between controllers.
All wiring must comply with National Electrical Code and local codes.
The ac power connections are in the top left corner of the Tracer ZN521 zone controller (see
Figure 3).