Trane CNT-SVX07C-EN, Zone Controller Two-pipe hydronic heating/cooling unit with auto changeover

Page 35

Wiring requirements and options

Figure 9. Two-pipe hydronic heating/cooling unit with auto changeover

Fan status (closed=on)*

Occupancy (open=occupied)*

Condensate overflow (closed=normal)*

Low-coil-temperature detection (closed=normal)*

24 Vac H N

24 V†

Fan, high speed

24 V†

Exhaust (or fan, medium speed)

24 V†

Fan, low speed

24 V†

Heating/cooling changeover valve

24 V†

Electric heat, stage 1 (optional)

		24 V†
		Electric heat, stage 2 (optional)
			24 V†
			Outdoor air damper actuator
	Open Close	Open Close	24 V†
	Open Close	Open Close	Generic/baseboard heat
			Generic/baseboard heat

Entering water

LonTalk temperature

Discharge air temperature

AI4 input: See	LonTalk
AI4 input: See	in
Figures 5 and 6
on page 20 for
wiring options	out
	out

Outdoor air or generic temperature

* All binary inputs are configurable.

†Connect 24 V to an AC POWER (24V) terminal.

CNT-SVX07C-EN

25

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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 Product description Overview and specificationsClearances DimensionsStorage environment Plastic-cover model dimensions and clearances Additional components Agency listing/complianceCO2 sensor Tracer zone temperature sensor optionsDamper actuators Zone humidity sensorOverview and specifications AC-power wiring Input/output terminal wiringGeneral wiring information Communication-link wiring and addressing General wiring information Operating environment requirements Location recommendationsMounting the Tracer ZN521 zone controller Mounting recommendationsHeatElectric Typical applications for the Tracer ZN521 zone controllerApplication SpeedfanMultiple Dehumidification ControlValve EconomizingBinary inputs BI1 Low-coil-temperature detectionBinary inputs BI2 Condensate overflowBI4 Fan status BI3 Occupancy or generic binary inputAnalog inputs ZN Zone temperatureAnalog inputs GND Ground terminalsSET Local setpoint FAN Fan mode inputAI1 Entering water temperature AI3 Outdoor air temperature or generic temperature AI2 Discharge air temperatureAI4 Universal 4-20 mA AI4 configuration options and associated measurement rangesConfiguration Measurement range AI4 terminal wiring CO2 measurement Binary output Functions Binary outputsGeneric binary output Binary output functionsFunction Input source For more information See Wiring requirements and optionsOverriding binary outputs Required controller inputs for proper operationTwo-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 Random start Power-up sequenceOccupancy modes Occupied modeUnoccupied mode Occupied standby modeTimed override control Occupied bypass modeSimplified zone control Zone temperature controlCascade zone control Morning cool-down Heating or cooling modeDischarge air tempering Morning warm-upFan operation Entering water temperature sampling functionExhaust control Exhaust controlValve control options Valve operationModulating valve operation Modulating valve calibrationTwo-pipe operation Modulating outdoor/return air dampersTwo-position valve operation Isolation-valve operationModulating outdoor air damper position Economizing free cooling Ashrae Cycle 1 conformanceAshrae Cycle 2 conformance Face-and-bypass, isolation-valve operation Two-position control of a modulating outdoor air damperFace-and-bypass damper operation DX cooling operationDehumidification Electric heat operationBaseboard heat operation Unit protection strategies Peer-to-peer communicationCondensate overflow Smart resetLow-coil-temperature protection Fan off delayFreeze avoidance Filter-maintenance timerFreeze protection discharge air temperature low limit Tracer ZN521 zone controller circuit board Test buttonManual output test Output For nonClose damper, air Outdoor Open damper, air Outdoor BOP1 BOP2 BOP3 BOP4 BOP5 BOP6 BOP7 BOP8 BOP9 Step ResultLED activity Explanation Service pin buttonRed LED Service indicator Interpreting LEDsYellow LED Communications indicator Green LED Status indicatorTypes of diagnostics DiagnosticsFan unaffected Table of diagnosticsDiagnostics Diagnostic Probable cause Consequences TypePosition Valved unaffectedDamper unaffected Status indicators for operation and communication Probable cause Explanation Fan does not energizeValves remain closed TroubleshootingDX or electric heat does not energize Valves remain openOutdoor air damper remains open Outdoor air damper remains closedOutdoor air damper remains open Troubleshooting Numerics IndexIndex Index Index Page Trane