Page 6 - IMPORTANT
CNT-SVX07C-EN NOTICE: Warnings and Cautions appear at appropriate sections throughout this manual. Read these carefully: WARNING Indicates a potentially hazardous situation, which, if not avoided, could result in death or serious injury. CAUTION Indicates a potentially hazardous situation, which...
Page 7 - Contents; Chapter 1
CNT-SVX07C-EN i Contents Chapter 1 Overview and specifications . . . . . . . . . . . . . . . . . . 1 Product description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Storage environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ....
Page 8 - Chapter 5
Contents ii CNT-SVX07C-EN Analog inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 GND: Ground terminals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 ZN: Zone temperature . . . . . . . . . . . . . . . . . . . . . . . . ....
Page 9 - Chapter 6
Contents CNT-SVX07C-EN iii Modulating outdoor/return air dampers. . . . . . . . . . . . . . . . . . . . . . . . . 43 ASHRAE Cycle 1 conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 ASHRAE Cycle 2 conformance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 Economi...
Page 10 - Chapter 7
Contents iv CNT-SVX07C-EN Chapter 7 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . 63 Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Page 11 - Overview and specifications; Product description
CNT-SVX07C-EN 1 Chapter 1 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 descrip-tions of ancillary products ...
Page 12 - Storage environment; Clearances
Chapter 1 Overview and specifications 2 CNT-SVX07C-EN 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...
Page 14 - Agency listing/compliance; Additional components; Power transformer; Binary input switching devices
Chapter 1 Overview and specifications 4 CNT-SVX07C-EN 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...
Page 15 - Damper actuators
Additional components CNT-SVX07C-EN 5 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 e...
Page 17 - Chapter 2; General wiring information; Input/output terminal wiring; WARNING
CNT-SVX07C-EN 7 Chapter 2 General wiring information This chapter provides specifications and general information about wir-ing the Tracer ZN521 zone controller. The controller requires wiring for: • Input/output terminals • AC power to the controller • Communication-link wiring, if the controller i...
Page 18 - CAUTION
Chapter 2 General wiring information 8 CNT-SVX07C-EN CAUTION Complete input/output wiring before applying power to the Tracer ZN521 zone controller. Failure to do so may cause damage to the con-troller or power transformer due to inadvertent connections to power circuits. IMPORTANT Do not share 24 V...
Page 21 - Chapter 3; Mounting the controller; Location recommendations; Operating environment requirements
CNT-SVX07C-EN 11 Chapter 3 Mounting the controller This chapter gives recommendations and requirements for mounting a Tracer ZN521 zone controller. Location recommendations Trane recommends locating the Tracer ZN521 zone controller: • Near the controlled piece of equipment to reduce wiring costs • W...
Page 22 - Mounting recommendations
Chapter 3 Mounting the controller 12 CNT-SVX07C-EN Mounting recommendations Mounting recommendations are as follows: CAUTION Mount the Tracer ZN521 zone controller with the cover on to avoid the possibility of damaging the circuit board during installation. • Mount the controller in any position, ot...
Page 23 - Chapter 4
CNT-SVX07C-EN 13 Chapter 4 Input/output functions and wiring for typical applications This chapter provides information about the function of inputs and out-puts and examples of wiring for typical applications. Applications sup-ported by the Tracer ZN521 zone controller are shown in Table 2. Figures...
Page 24 - Binary inputs; BI2: Condensate overflow
Chapter 4 Input/output functions and wiring for typical applications 14 CNT-SVX07C-EN Binary inputs The Tracer ZN521 controller includes four binary inputs. Each binary input associates an input signal of 0 Vac with open contacts and 24 Vac with closed contacts. You can use the Rover service tool to...
Page 25 - BI3: Occupancy or generic binary input
Binary inputs CNT-SVX07C-EN 15 BI3: Occupancy or generic binary input The BI3 binary input can function as either: • The occupancy input • A generic binary input The function of occupancy is to save energy by spreading zone setpoints when the zone is unoccupied. As the occupancy input, BI3 can be us...
Page 26 - Analog inputs; GND: Ground terminals
Chapter 4 Input/output functions and wiring for typical applications 16 CNT-SVX07C-EN Analog inputs The Tracer ZN521 controller includes seven analog inputs. Table 4 describes their functions. Each function is explained in the following paragraphs. For an explanation of the diagnostics generated by ...
Page 27 - AI1: Entering water temperature
Analog inputs CNT-SVX07C-EN 17 SET: Local setpoint The SET analog input functions as the local (hard-wired) temperature setpoint input for applications utilizing a Trane zone sensor with a tem-perature setpoint thumbwheel. The local setpoint input is configurable (as enabled or disabled) using the R...
Page 28 - AI2: Discharge air temperature; AI3: Outdoor air temperature or generic temperature
Chapter 4 Input/output functions and wiring for typical applications 18 CNT-SVX07C-EN For units not configured as changeover units, the entering water temper-ature value is used for information and troubleshooting only and does not affect the operation of the controller. AI2: Discharge air temperatu...
Page 31 - Binary outputs; Generic binary output
Binary outputs CNT-SVX07C-EN 21 Binary outputs The ZN521 zone controller supports fan coil, blower coil, and unit ventila-tor applications that may include the following components: • Supply fan with up to three speeds • Hydronic cooling and/or heating coils with two-position or tri-state modulating...
Page 32 - Overriding binary outputs; Wiring requirements and options
Chapter 4 Input/output functions and wiring for typical applications 22 CNT-SVX07C-EN Overriding binary outputs The Tracer ZN521 controller includes a manual output test and a water valve override feature. Use the manual output test to manually control the outputs in a defined sequence. For informat...
Page 45 - Sequence of operations; Random start
CNT-SVX07C-EN 35 Chapter 5 Sequence of operations The Tracer ZN521 zone controller will operate to maintain the zone tem-perature setpoint. This chapter discusses many of the operational sequences used by the controller to accomplish this goal. Power-up sequence When 24 Vac power is initially applie...
Page 46 - Occupancy modes; Occupied mode
Chapter 5 Sequence of operations 36 CNT-SVX07C-EN Occupancy modes Occupancy modes can be controlled by any of the following: • The state of the local (hard-wired) occupancy binary input BI3 (see “BI3: Occupancy or generic binary input” on page 15) • A timed override request from a Trane zone sensor ...
Page 47 - Occupied bypass mode; Timed override control
Timed override control CNT-SVX07C-EN 37 The fan will run as configured (continuous or cycling) for occupied mode. The controller always uses the stored default setpoint values (config-urable using the Rover service tool), regardless of hard-wired or commu-nicated setpoint values. In addition, the ou...
Page 48 - Zone temperature control; Cascade zone control; Simplified zone control
Chapter 5 Sequence of operations 38 CNT-SVX07C-EN Zone temperature control The Tracer ZN521 zone controller uses two methods of zone temperature control: • Cascade zone control—used in the occupied, occupied bypass, and occupied standby modes • Simplified zone control—used in the unoccupied mode Cas...
Page 49 - Discharge air tempering
Discharge air tempering CNT-SVX07C-EN 39 Discharge air tempering If the controller is in cooling mode, cascade zone control initiates a dis-charge air tempering function when the discharge air temperature falls below the Discharge Air Control Point Low Limit (configurable using the Rover service too...
Page 50 - Fan operation
Chapter 5 Sequence of operations 40 CNT-SVX07C-EN In heating and cooling mode, the controller maintains the zone tempera-ture based on the active heating setpoint and the active cooling setpoint, respectively. The active heating and cooling setpoints are determined by the occupancy mode of the contr...
Page 51 - Exhaust control
Exhaust control CNT-SVX07C-EN 41 fan configuration. The controller can be configured to auto, to a specific fan speed, or to off. If both a communicated and hard-wired value (fan-speed switch) is present, the communicated value has priority. When the controller receives a communicated auto signal (o...
Page 52 - Valve operation; Modulating valve operation
Chapter 5 Sequence of operations 42 CNT-SVX07C-EN • The exhaust output is de-energized if the outdoor air damper position drops 10% below the Exhaust Fan/Damper Enable Setpoint. • If the Exhaust Fan/Damper Enable Setpoint is less than 10%, the exhaust output is energized if the outdoor air damper po...
Page 53 - Two-position valve operation; Modulating outdoor/return air dampers
Modulating outdoor/return air dampers CNT-SVX07C-EN 43 Two-position valve operation The Tracer ZN521 supports two-position valves with a single binary out-put for each valve. Controllers used for two-pipe applications support heating, cooling, or heat/cool changeover with a single valve/coil. Contro...
Page 55 - ASHRAE Cycle 1 conformance
Modulating outdoor/return air dampers CNT-SVX07C-EN 45 ASHRAE Cycle 1 conformance Tracer ZN521 applications with an outside air damper support ASHRAE Cycle 1 conformance. ASHRAE Cycle 1 operation admits 100% outdoor air at all times except during a warm-up cycle. A tri-state modulating damper actuat...
Page 56 - DX cooling operation
Chapter 5 Sequence of operations 46 CNT-SVX07C-EN Two-position control of a modulating outdoor air damper The Tracer ZN521 does not support a two-position outdoor air damper actuator. However, a modulating outdoor/return air damper actuator can be used for two-position control. Two-position control ...
Page 57 - Electric heat operation
Electric heat operation CNT-SVX07C-EN 47 Electric heat operation The Tracer ZN521 supports both single-stage and two-stage electric heat. Electric heat is cycled on and off to maintain the discharge air tempera-ture at the active heating setpoint. Two-pipe changeover units with elec-tric heat use th...
Page 58 - Unit protection strategies
Chapter 5 Sequence of operations 48 CNT-SVX07C-EN Peer-to-peer communication Tracer ZN521 zone controllers have the ability to share data with other LonTalk-based controllers. Multiple controllers can be bound as peers, using the Rover service tool, to share: • Setpoint • Zone temperature • Heating/...
Page 59 - Smart reset; Fan status
Unit protection strategies CNT-SVX07C-EN 49 Smart reset The Tracer ZN521 will automatically restart a unit that is locked-out as a result of a Low Coil Temp Detection (BI1) diagnostic. Referred to as “smart reset,” this automatic restart will occur 30 minutes after the diag-nostic occurs. If the uni...
Page 60 - Filter-maintenance timer
Chapter 5 Sequence of operations 50 CNT-SVX07C-EN Filter-maintenance timer The filter-maintenance timer tracks the amount of time (in hours) that the fan is enabled. The Maintenance Required Timer Setpoint (config-urable using the Rover service tool) is used to set the amount of time until maintenan...
Page 62 - Manual output test
Chapter 6 Status indicators for operation and communication 52 CNT-SVX07C-EN Manual output test The manual output test sequentially turns on and off all binary outputs to verify their operation. The test overrides normal operation of the con-troller, which is suspended while the test is being perfor...
Page 66 - Service pin button; Interpreting LEDs
Chapter 6 Status indicators for operation and communication 56 CNT-SVX07C-EN Service pin button The Service pin button is located as shown in Figure 19 on page 51. The Service pin button is used to: • Identify a device (see “Identifying a device” in the Rover Installation/ Operation/Programming guid...
Page 68 - Diagnostics; Types of diagnostics
Chapter 6 Status indicators for operation and communication 58 CNT-SVX07C-EN Diagnostics Diagnostics are informational messages that indicate the operational sta-tus of the controller. In response to most diagnostics, the controller attempts to protect the equipment by enabling or disabling, or open...
Page 69 - Smart reset diagnostics; Table of diagnostics
Diagnostics CNT-SVX07C-EN 59 Smart reset diagnostics After the controller detects the first smart reset diagnostic, the unit waits 30 minutes before initiating the smart reset function. If another diagnos-tic of this type occurs again within 24 hours after an automatic clearing, you must clear the d...
Page 73 - Troubleshooting
CNT-SVX07C-EN 63 Chapter 7 Troubleshooting Use Table 17 through Table 22 to assist you in diagnosing any of the fol-lowing operational problems that you might encounter with the Tracer ZN521 zone controller: • Fan does not energize (Table 17) • Valves remain closed (Table 18 on page 64) • Valves rem...
Page 79 - Index; Numerics
CNT-SVX07C-EN 39 Index Numerics 24 Vac wiring, 7 A AC-power wiring, 7 Actuators Damper, 5, 46Valve, 4 Additional application-dependent components, 4–5 Addressing LonTalk communication, 9Neuron IDs, 9 Agency listing/compliance, 3 Analog inputs, 16–20 AI1 (Entering water temperature), 17 AI2 (Discharg...
