Trane ZN.520 - Manual

10 UV-SVP01A-EN Controller Features Each Tracer ZN.520 unit controller circuit board is equipped with en- hancements to help facilitate ser- vice, testing, and diagnosis.Each board has q Manual test button, q Status LED, q Communication status LED, q Service button, q Quick terminal connectors, and ...

UV-SVP01A-EN 11 Communication Configurations Note: The Tracer ZN.520 is a configured controller. It will not operate without a valid downloaded configuration file. The Tracer ZN.520 controller sup- ports ICS and peer-to-peer com- munications as well as stand- alone operation. A number of con- trol f...

12 UV-SVP01A-EN Communication Configurations Stand-Alone In a stand-alone configuration, commands for operation are deter- mined based on input from the zone sensor, humidity sensor, and factory- or field-mounted time- clock. (See Figure 6: “ Typical class- room unit ventilator installation”) q The ...

UV-SVP01A-EN 13 Table 2: End Device Specifications Device Characteristic Description Fan Status Switch Material Contact Blade—Pilot duty rated Operating Temperature Range - 4 0 ° F / 2 5 0 ° F ( - 4 0 ° C / 1 2 0 ° C ) Contact Form SPST-NO Preset Fan status - 0.07” Low Temperature Detection Switch (...

18 UV-SVP01A-EN Specifications Dimensions Tracer ZN.520 board and mounting hardware:• Height: 5.25 inches (133 mm.) • Width: 5.50 inches (140 mm) • Depth: 2.25 inches (57 mm) Power Requirements • 18 to 32 VAC (24 VAC nominal) • 50 or 60 Hz • 570 mA AC Operating Environment • 32° to 140°F (0× to 60°C...

UV-SVP01A-EN 19 Binary Inputs Each binary input associates an in- put signal of 0 VAC with open con- tacts and 24 VAC with closed contacts. Table 3: Binary inputs (typically 24 mA AC) Description Terminals Terminal Function Binary input 1(BI 1) J2-1 24 VAC J2-2 Input Binary input 2(BI 2) J2-3 24 VAC...

20 UV-SVP01A-EN Binary Outputs Outputs are load side switching tri- acs. The triac acts as a switch, ei- ther making or breaking the circuit between the load (valve, damper, contactor, relay) and ground. Generic/baseboard Heat Binary Output Table 4: Binary outputs Description Terminals Output Rating...

UV-SVP01A-EN 21 Analog Inputs Table 6: Analog inputs 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 Setpoint input 40 ° to 115 ° F (4.4 ° to 46.1 ° C) Fan TB3-4 Fan switch input 4821 to 4919 Ω (Off) 229...

22 UV-SVP01A-EN Mounting The Tracer ZN.520 circuit board is mounted in the left-hand end pock- et for all classroom unit ventilator configurations. The sheet metal mounting plate has raised emboss- es to accept the mounting feet on the circuit board. (See Figure 8: “Classroom unit ventilator control...

24 UV-SVP01A-EN Wiring Warning! Disconnect all elec-trical power before servicing unit to prevent injury or death due to electrical shock. Use copper conductors only. The use of aluminum or other incorrect types of wire may result in overheating and equipment damage. Caution: To prevent damage to th...

UV-SVP01A-EN 25 Installing the Wall- Mounted Zone Sensor (Optional) Zone sensor location is an impor- tant element of effective room control and comfort.The best sensor location is typical- ly on a wall, remote from the HVAC unit. Readings at this loca- tion assure that the desired set- point is ach...

UV-SVP01A-EN 29 Typical Wiring Diagram— Unit Mounted Switch, Wall Mounted Sensor

32 UV-SVP01A-EN Note: The Tracer Zn.520 unit controller only supports cascade control by controlling the discharge air temperature. Therefore, the controller requires both a space temperature input and a discharge air temperature input. Trane configures the Tracer ® ZN.520 Unit Controller at the fac...

UV-SVP01A-EN 35 Configuration Fan Configuration End Device Configurations 1. The exhaust fan is energized when the outdoor air damper is equal to or greater than the exhaust fan enable point, and the exhaust fan is turned off when the outdoor air damper is 10% less than the exhaust fan enable point....

36 UV-SVP01A-EN Configuration Setpoints 1. The heating and cooling setpoint high and low limits only apply to the occupied and occupied standby setpoints and are never applied to the unoccupied setpoints. Discharge Air Limits 1. The low limit is the temperature at which the controller shuts down the...

UV-SVP01A-EN 37 Configuration Occupied Bypass Timer 1. The occupied bypass timer is used for timed override applications. Power-Up Control Wait Maintenance Timers Table 18: Bypass timer range Default Valid range Occupancy bypass timer 1 120 Minutes 0 to 240 minutes (1 minute resolution) Table 19: Co...

38 UV-SVP01A-EN 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 top portion of the unit identifi- cation tag remains permanently af- ...

UV-SVP01A-EN 39 Power-Up When 24 VAC is initially applied to the controller, the following se- quence of events occurs: q Green status LED turns ON . q All outputs are controlled OFF . q The controller reads input values to determine initial values. q Random-start timer expires (5 to 30 seconds). q ...

UV-SVP01A-EN 41 The entering water must be five degrees or more above the space temperature to allow hydronic heating, and five degrees or more below the space temperature to al- low hydronic cooling.If the desired water temperature is available, the unit begins normal heating and cooling operation....

42 UV-SVP01A-EN Unit Operation seconds. This provides the ample torque required to start all fan mo- tors from the off position. Exhaust fan/damper operation This binary point is a shared point with medium fan speed. For this point to be used for exhaust con- trol, the controller must be config- ure...

44 UV-SVP01A-EN Unit Operation Automatic Outdoor Air Damper Adjustment The Tracer ZN.520 controller is ca- pable of using different minimum outdoor air damper positions for high and low fan speeds, which are configurable. This allows the venti- lation rate to be maintained when switching between fan...

UV-SVP01A-EN 45 Unit Operation than or equal to the configurable exhaust enable setpoint. This is useful for exhaust fans designed to offset the added economizer ventilation. The exhaust fan is disabled when the outdoor air damper position drops 10% below the exhaust en- able point. If the exhaust f...

46 UV-SVP01A-EN Unit Operation OFF due to a safety or command. The controller enters the F RE EZE A VO ID A N CE mode when an out- door air temperature is present (communicated or hardwired) and it is below the freeze avoidance set- point (configurable). The controller disables freeze avoidance when...

48 UV-SVP01A-EN Important! When viewing the Tracer ZN.520 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. Led Operation Red Service LED Black Service P...

UV-SVP01A-EN 49 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 54.for more information.) Test Proced...

UV-SVP01A-EN 51 Troubleshooting Safeties Freeze Protection The Tracer ZN.520 controller has two methods of freeze protection. 1. An optional binary freezestat that is wired to a binary input. The freezestat is a capillary tube type and is factory set to 35 °F. When this device opens, a “Low Coil Tem...

UV-SVP01A-EN 52 Troubleshooting Diagnostics Table 28: Tracer™ ZN.520 Unit Controller diagnostics Diagnostic Unit Response Latching/non- latching Reset Low Coil Temperature Detect 2 Fan— OFF Valves— OP EN Outdoor air damper— CLOS ED Face bypass damper— BY PAS S DX/electric heat— OFF Baseboard heat— O...

UV-SVP01A-EN 54 Troubleshooting Note 1 : The generic binary output (TB4-1, TB4-2) state is unaffected by all unit diagnostics. Note 2 : During manual output test, these diagnostics make the green status LED light in a two-blink pattern. For more information see, Manual Output Test, on page 48 for mo...

UV-SVP01A-EN 55 Troubleshooting power, 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 pow-er-up are handled according to the defined unit diagnosti...

UV-SVP01A-EN 56 Troubleshooting Valves Table 30: 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. Random-start observed After power-up, the controller always observes ...

UV-SVP01A-EN 57 Troubleshooting DX/Electric Heat Outside Air Damper Freeze avoidance When the fan is off with no demand for capacity (0%) and the outdoor air temperature is below the freeze avoidance setpoint, the controller opens the water valves (100%) to prevent coil freezing. This includes unocc...

UV-SVP01A-EN 59 Replacing Circuit Boards Tracer ZN.520 Unit Controller Replacement 1. Disconnect power or disable the circuit breaker to unit. 2. Remove bad or questionable Tracer ZN.520 controller cir-cuit board. 3. Install controller in the unit with the heat-sink placement at the top of the contr...

60 UV-SVP01A-EN Hardwired Setpoint Adjustment Fan Switch Resistance Values Hardwired Thermistor Values Table 35: Hardwired setpoint adjustment Resistance ( Ω ) Setpoint (Deg 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 Table 36: Resistance values Resistance ( Ω )...

UV-SVP01A-EN 61 Binary Configuration 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 ...

62 UV-SVP01A-EN Appendix—Unit Operation Unit Operation Based On The Effective H EAT / CO OL Output Table 39: Unit operation based on the effective heat/cool output Application mode input (nviApplicMode) Heat/cool mode input (nviHeatCool) Effective heat/ cool mode output (nvoHeatCool) Unit Operation ...

64 UV-SVP01A-EN Appendix—Data Lists Data Lists Table 70 provides an input/output listing for the Tracer ZN.520 unit controller. The content of the lists conforms to both the LonMark Space Comfort Controller Functional Profile and the LonMark node object. 1. LonMark certification pending Note 1 : Lon...

UV-SVP01A-EN 65 Appendix—Timeclock Setting the Time Clock The time clock must be pro- grammed for the unit to operate in occupied mode (under load). If not programmed, the unit will run in the unoccupied mode. Power must be supplied to the unit for the time clock to be set. The following procedure c...

66 UV-SVP01A-EN Appendix—Timeclock the unit will respond differently to changing conditions and maintain a higher comfort level.For unoccupied operation or “no load” conditions, a lower comfort level is provided. The load can be switched off by using the program for periods when the room will be uno...

68 UV-SVP01A-EN Appendix—Location Identifier This area provided for the removable tag.