Trane N512, Zone Controller, CNT-SVX07C-EN Peer-to-peer communication, Unit protection strategies

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Chapter 5 Sequence of operations

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/cooling mode

•Fan status

•Unit capacity control

Shared data is communicated from one controller to any other controller that is bound to it as a peer. Applications having more than one unit serv- ing a single zone can benefit by using this feature; it allows multiple units to share a single zone temperature sensor and prevents multiple units from simultaneously heating and cooling.

Unit protection strategies

The following strategies are initiated when specific conditions exist in order to protect the unit or building from damage:

•Smart reset

•Low-coil-temperature protection

•Condensate overflow

•Fan status

•Fan off delay

•Filter-maintenance timer

•Freeze avoidance

•Freeze protection (discharge air temperature low limit)

48	CNT-SVX07C-EN

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Contents Installation and Operation Tracer ZN521 Zone Controller Page CNT-SVX07C-EN April CNT-SVX07C-EN Tracer ZN521 Zone Controller Installation and Operation CNT-SVX07C-EN Contents Sequence of operations Status indicators for operation and communication Troubleshooting Index Overview and specifications Product descriptionStorage environment DimensionsClearances Plastic-cover model dimensions and clearances Agency listing/compliance Additional componentsZone humidity sensor Tracer zone temperature sensor optionsDamper actuators CO2 sensorOverview and specifications Input/output terminal wiring AC-power wiringGeneral wiring information Communication-link wiring and addressing General wiring information Location recommendations Operating environment requirementsMounting recommendations Mounting the Tracer ZN521 zone controllerControlValve Economizing Typical applications for the Tracer ZN521 zone controllerApplication SpeedfanMultiple Dehumidification HeatElectricBI2 Condensate overflow BI1 Low-coil-temperature detectionBinary inputs Binary inputsBI3 Occupancy or generic binary input BI4 Fan statusGND Ground terminals ZN Zone temperatureAnalog inputs Analog inputsAI1 Entering water temperature FAN Fan mode inputSET Local setpoint AI2 Discharge air temperature AI3 Outdoor air temperature or generic temperatureConfiguration Measurement range AI4 configuration options and associated measurement rangesAI4 Universal 4-20 mA AI4 terminal wiring CO2 measurement Binary output functions Binary outputsGeneric binary output Binary output FunctionsRequired controller inputs for proper operation Wiring requirements and optionsOverriding binary outputs Function Input source For more information SeeTwo-pipe hydronic-cooling unit Two-pipe hydronic-heating unit Two-pipe hydronic heating/cooling unit with auto changeover Four-pipe hydronic heating/cooling unit Four-pipe heating/cooling unit with auto changeover Two-pipe heating unit with DX cooling Electric heat unit with DX cooling Electric heat unit Two-pipe heating unit with face-and-bypass damper Two-pipe heating/cooling unit with face-and-bypass damper Four-pipe heating/cooling unit with face-and-bypass damper Input/output functions and wiring for typical applications Power-up sequence Random startOccupied standby mode Occupied modeUnoccupied mode Occupancy modesOccupied bypass mode Timed override controlCascade zone control Zone temperature controlSimplified zone control Morning warm-up Heating or cooling modeDischarge air tempering Morning cool-downEntering water temperature sampling function Fan operationExhaust control Exhaust controlModulating valve calibration Valve operationModulating valve operation Valve control optionsIsolation-valve operation Modulating outdoor/return air dampersTwo-position valve operation Two-pipe operationModulating outdoor air damper position Ashrae Cycle 2 conformance Ashrae Cycle 1 conformanceEconomizing free cooling DX cooling operation Two-position control of a modulating outdoor air damperFace-and-bypass damper operation Face-and-bypass, isolation-valve operationBaseboard heat operation Electric heat operationDehumidification Peer-to-peer communication Unit protection strategiesFan off delay Smart resetLow-coil-temperature protection Condensate overflowFreeze protection discharge air temperature low limit Filter-maintenance timerFreeze avoidance Test button Tracer ZN521 zone controller circuit boardManual output test For non OutputClose damper, air Outdoor Open damper, air Outdoor Step Result BOP1 BOP2 BOP3 BOP4 BOP5 BOP6 BOP7 BOP8 BOP9Interpreting LEDs Service pin buttonRed LED Service indicator LED activity ExplanationGreen LED Status indicator Yellow LED Communications indicatorDiagnostics Types of diagnosticsDiagnostic Probable cause Consequences Type Table of diagnosticsDiagnostics Fan unaffectedValved unaffected PositionDamper unaffected Status indicators for operation and communication Fan does not energize Probable cause ExplanationTroubleshooting Valves remain closedValves remain open DX or electric heat does not energizeOutdoor air damper remains closed Outdoor air damper remains openOutdoor air damper remains open Troubleshooting Index NumericsIndex Index Index Page Trane