Carrier 50TCA04-A07 appendix Oat ≤ Spt

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50TC

return to normal when the indoor relative humidity drops 3% below the active humidity setpoint.

Economizer — The economizer dampers are used to provide free cooling and indoor air quality if optional CO2 sensor is installed and when the outside conditions are suitable. Temperature control is accomplished by controlling the SAT to a certain level determined by the Economizer PID Loop by calculating a submaster reference (ECONSR) value. This algorithm will calculate the submaster reference temperature (ECONSR) based on OAT and enthalpy conditions and cooling requirements. The ECONSR value is then passed to the Economizer Submaster Loop, which will modulate dampers to maintain SAT at ECONSR level.

The following conditions are required to determine if economizer cooling is possible:

S Indoor fan has been on for at least 30 seconds S Enthalpy is low

S SAT reading is available S OAT reading is available S SPT reading is available

S OAT ≤ SPT

SOAT < OATMAX (OATMAX default is 75_F) S Economizer position is NOT forced

If any of the above conditions are not met, the ECONSR will be set to its MAX limit of 120_F and the damper will go to its configured minimum position. The minimum damper position can be overridden by the IAQ routine described later in this section.

The calculation for ECONSR is as follows:

ECONSR = PID function on (setpoint - SPT), where:

setpoint = ((OCSP+STO) + (OHSP+STO))/2 when NTLO (Unoccupied Free Cool OAT Lockout) < OAT < 68_F

setpoint = (OCSP+STO) - 1 when OAT ≤ NTLO setpoint = (OHSP+STO) + 1 when OAT ≥ 68_F

The actual damper position (ECONPOS) is the result of the following calculation. Values represented in the right side of the equation can be found in the SERVICE configuration table descriptions in this manual. Note that that the OAT is taken into consideration to avoid large changes in damper position when the OAT is cold:

ECONPOS = SubGain x (ECONSR-SAT) + CTRVAL where SubGain = (OAT - TEMPBAND) / (ESG + 1)

If the OAT < DXLOCK (DX Cool Lockout setpoint) then the damper will be modulated to maintain the SAT at the ECONSR value.

If the OAT is between DXLOCK and 68_F (DXLOCK < OAT < 68_F) and additional cooling is required, the economizer will close the to minimum position for three minutes, the economizer integrator will then be reset to 0 and begin modulating to maintain the SASP after the stage has been energized for about 90 seconds. This will allow the economizer to calculate a new ECONSR that takes

into account the cooling effect that has just been turned on and not return to the value require before the cooling was added. This will prevent the economizer from causing premature off cycles of compressors while maintaining the low SAT temperature setpoint for the number of stages active. In addition to preventing compressor short cycling, by using return air across the evaporator coil just after the compressor has started allows for increased refrigerant flow rates providing for better oil return of any oil washed out during compressor start-up.

If the OAT > 68_F and OAT < SPT and the number of DX stages requested is > 0 by the staging algorithm, then ECONSR is set to its minimum value 48_F and the damper will go to 100% open.

If the Auxiliary Relay is configured for exhaust fan (AUXOUT = 1) in the CONFIG configuration table and Continuous Power Exhaust (MODPE) is Enable in the SERVICE configuration table, then the AUXO output (HS3) will be energized whenever the PremierLink controller is in the occupied mode. If the MODPE is disabled then AUXO output will be energized based on the Power Exhaust Setpoint (PES) in the SETPOINT table.

Heating — The heat stages are controlled by the Heating Control Loop, which is used to calculate the desired SAT needed to satisfy the space. It will compare the SPT to the Occupied Heat Setpoint (OHSP) + the T56 slider offset (STO) when occupied and the Unoccupied Heat Setpoint (UHSP - Unoccupied Heating Deadband) if unoccupied to calculate a Staged Heat Submaster Reference (SHSR). The heat staging algorithm compares the SHSR to the actual SAT to calculate the required number of heating stages to satisfy the load. This loop runs every 40 seconds. The following conditions must be met in order for this algorithm to run:

S Indoor fan has been ON for at least 30 seconds.

S Cool mode is not active and the time guard between modes equals zero.

S Mode is occupied or the Temperature Compensated Start or Heat mode is active.

S SPT reading is available and < (OHSP + STO).

S If it is unoccupied and the SPT < (UHSP - Unoccupied Heating Deadband). The indoor fan will be turn on by the staging algorithm.

When all of the above conditions are met, the SHSR is calculated and up to 3 stages of heat will turned on and off to satisfy to maintain the SAT = SHSR. If any of the above conditions are not met, the SHSR is set to its minimum value of 35_F.

The Staged Heat Submaster Reference (SHSR) is calculated as follows:

SHSR = Heating PID function on (error) where error = (OHSP + STO) - Space Temperature

The Maximum SHSR is determined by the SATHI configuration. If the supply-air temperature exceeds the SATHI configuration value, then the heat stages will turn

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Contents Table of Contents Safety ConsiderationsSeasonal Maintenance Unit Arrangement and AccessRoutine Maintenance GeneralSupply FAN Blower Section Supply Fan Belt-DriveAdjustable-Pitch Pulley on Motor Supply-Fan Pulley Adjustment BearingsCooling Condenser Coil Maintenance and Cleaning RecommendationCondenser Coil Cleaning Condenser Coil Two-Row CoilsEvaporator Coil Refrigerant System Pressure Access PortsPuronr R-410A Refrigerant Refrigerant ChargeTo Use Cooling Charging Charts CoreMax Access Port AssemblyCooling Charging Charts Cooling Charging ChartsCooling Charging Charts Filter Drier Troubleshooting Cooling SystemCompressor Condenser-Fan LocationCooling Service Analysis Problem Cause RemedyConvenience Outlets Smoke DetectorsController SystemSensor Completing Installation of Return Air Smoke Sensor Smoke Detector LocationsFiop Smoke Detector Wiring and Response Return Air Sensor Operating PositionDirty Controller Test Sensor and Controller Tests Sensor Alarm TestController Alarm Test Dirty Sensor TestCleaning the Smoke Detector Detector CleaningRemote Test/Reset Station Dirty Sensor Test Changing the Dirt Sensor TestDetector Indicators IndicatorsAlarm State Control or Indicator DescriptionTroubleshooting Protective DevicesControl Circuit Electric HeatersRelief Device Condenser Fan Motor ProtectionCompleting Heater Installation Typical Single Point InstallationPremierlinkt Control PremierLink ControllerPremierLink Wiring Schematic 55 Space Temperature Sensor Wiring Temp ResistancePremierLink Sensor Usage Temperature Enthalpy SensorOutdoor AIR Return AIR Field Connection Input Signal Space Sensor ModeThermostat Mode TB1 Terminal Field Connection Input SignalLctb Outside and Return Air Enthalpy Sensor Wiring Indoor CO2 Sensor 33ZCSENCO2 Connec TionsColor Code Recommendations CCN BUS Wire CCN Plug PIN Color NumberRecommended Cables ManufacturerEconomizer Systems PremierLink CCN Bus ConnectionsInputs Outputs RUNOutdoor Air Lockout Sensor Supply Air Temperature SAT SensorEconoMi$er EconoMi$er IV Control ModesDifferential Dry Bulb Control Outdoor Enthalpy ChangeoverEnthalpy Changeover Setpoints Indoor Air Quality IAQ Sensor InputDamper Movement Exhaust Setpoint AdjustmentMinimum Position Control ThermostatsDemand Control Ventilation DCV CO2 Sensor ConfigurationEconoMi$er IV Sensor Usage Differential Enthalpy DCV Demand Controlled Ventilation and Power ExhaustEconoMi$er IV Preparation Single EnthalpyEconoMi$er IV Troubleshooting Completion Wiring DiagramsPRE-START-UP START-UP, General START-UP, Premierlink ControlsInitial Operation and Test Memory ResetPerform System Check-Out Operating Sequence, Base Unit ControlsOperating Sequence, PremierLink Control 50TC Available Cooling Stages Number Stages EconomizerOAT ≤ SPT 50TC 50TC Fastener Torque Values Loadshed Command Gas and Electric Heat UnitsLinkage Modes 50TC Typical Unit Wiring diagram Power A06 Torque Values50TC Unit Wiring Diagram Control A06 Serial Number Format Appendix I. Model Number SignificanceModel Number Nomenclature Position Number Typical DesignatesAppendix II. Physical Data Physical Data Cooling TonsAppendix III. FAN Performance General Fan Performance NotesTon Vertical Supply Ton Horizontal SupplyCFM RPM BHP Standard Static Option 5541215 11701165 1225 120650TC**05 Phase Ton Horizontal Supply 724 765Phase Ton Horizontal Supply 923 1019 822 927 1018872 973 1061 974 1067Pulley Adjustment Unit MOTOR/DRIVE Motor Pulley Turns Open ComboAppendix IV. Electrical Data Appendix IV. Electrical Data FLAMCA/MOCP Determination no C.O. or Unpwrd C.O MCA/MOCP Determination no C.O. or Unpwrd C.O. 78/89152 159 Appendix V. Wiring Diagram List Wiring DiagramsAppendix VI. Motormaster Sensor Locations 50TC*A04 Outdoor CircuitingAppendix VI. cont Motormaster Sensor Locations Catalog No 50TC---1SM Pressures Cooling Mode START-UP ChecklistRemove and Store in Job File

50TCA04-A07 specifications

The Carrier 50TCA04-A07 is a prominent model from Carrier, a leader in the heating, ventilation, and air conditioning (HVAC) industry. Designed for commercial applications, this unit exemplifies advanced technology and reliability, catering to a wide array of cooling needs.

One of the most notable features of the Carrier 50TCA04-A07 is its high efficiency. With a cooling capacity that suits various settings, it is engineered to provide excellent performance with minimal energy consumption. The unit achieves impressive Seasonal Energy Efficiency Ratio (SEER) ratings, which not only reduce operational costs but also lower the environmental impact.

The Carrier 50TCA04-A07 employs state-of-the-art inverter technology. This innovation allows the compressor to operate at varying speeds, adjusting its output according to the cooling demand. Consequently, the system can maintain optimal comfort levels while using less energy. Additionally, the inverter technology contributes to quieter operation, making it a suitable choice for environments where noise is a concern.

Durability is a hallmark of the Carrier 50TCA04-A07. Constructed with robust materials, this model is designed to withstand harsh conditions and ensure long-term reliability. The unit is equipped with corrosion-resistant components, extending its lifespan and maintaining performance quality over time.

Another significant characteristic of the Carrier 50TCA04-A07 is its advanced control system. The integrated control panel provides easy access to performance settings and monitoring capabilities. Users can effortlessly adjust temperatures and modes, ensuring a customizable climate. Furthermore, compatibility with smart building management systems enhances operational efficiency and real-time monitoring.

Regarding safety features, the Carrier 50TCA04-A07 is equipped with multiple sensors and automated responses to prevent overheating and ensure safe operation. These safety mechanisms not only protect the unit but also contribute to the overall safety of the installation environment.

In summary, the Carrier 50TCA04-A07 is a highly efficient, durable, and technologically advanced HVAC solution for commercial spaces. Its innovative features, including inverter technology, robust construction, and smart control systems, set it apart in the market, making it a reliable choice for businesses seeking to optimize their climate control needs while minimizing energy consumption and operational costs.
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