Carrier 50XJ064-104 specifications Operation

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OPERATION

Occupancy Determination — The OMNIZONE™ controller can determine occupancy in many ways. Local occu- pancy is determined by either a local schedule contained in the CC6400 controller, the use of the ROCC discrete input point or by setting the Local/Off/Remote switch to Local. In order for the CC6400 schedule or ROCC point to function the Local/ Off/Remote switch must be set to Remote.

When the OMNIZONE unit is connected to a Carrier Comfort Network and the Local/Off/Remote switch is set to Remote, the controller occupancy can be determined by a Network Group schedule, a Network Global schedule, or via Linkage from a linkage device such as a ComfortID™ linkage master.

Fan Control — All Variable Air Volume (VAV) units have a Variable Frequency Drive (VFD) to provide variable fan motor speed and thus variable airflow. Fan control turns the fan on and off based on unit operating mode, and controls fan speed to maintain a particular duct static pressure at a Duct Static Pressure Sensor (DSP). The objective is to maintain a reasonably constant supply-air exit velocity at VAV system outlet grilles, regardless of damper opening positions. The duct static pressure sensor is field-installed about 2/3 of the way toward the “far end” of the ductwork. A High Duct Static Switch (HDS) provides protection by shutting the fan down if the duct static pressure exceeds a maximum setting.

For the 50XJ unit, a VFD interface display is mounted in the front of the unit. A number of user-adjustable features can be entered/changed using the keypad on the display. These features described in detail in the Variable Frequency Drive Control section.

Sequence of Operation — The following control sequence of operation for the 50XJ,BV unit describes the various sequences that occur depending upon the way an operation is triggered and which software control points are involved.

SUPPLY FAN — The Supply fan can be activated in any of the following ways:

•Unoccupied space or return air temperature demand.

•Unoccupied Linkage demand.

•Local Time Schedule (TIMCLOCK software point).

•Remote Occupancy (ROCC software point).

•By placing the remote-off-local switch in the local mode.

•Enabled by Schedule.

Once one of the above conditions exists, either TIME- CLOCK or ROCC indicates ON or Enable. The software point OKFAN will turn on followed by the points TRMCT for air terminal control and PUMP and TOWER to request condenser water flow and temperature control. Approximately 20 to 30 seconds later the supply fan (SF) point will turn ON and the VFD output SPEED will increase. The SPEED point will output a signal, determined by a PID calculation, based on the duct static pressure DSP input and the Supply Static Pressure set point in SETPT05.

Once the supply fan is running and the static pressure increases above the Supply fan status set point in SETPT01, the supply fan status point (SFS) will indicate ON and the software point SF_SFS will indicate TRUE.

Enabled By Unoccupied Demand — A software point “Space Control Point” will display the current value of the sensor used to determine unoccupied demand. The EWT sensor provides this function for the 50BV unit. The display is based on the

sensors installed and the configuration of these sensors in the custom configuration, or the status of linkage.

If the Return/Mixed air sensor is in the mixed airstream and configured as such and there is no Space temperature sensor installed and no Linkage, the Space Control Point will display a default value of 75 F, which is above the default occupied cooling set point and below the unoccupied cooling set point. If this condition exists, supply air reset from a sensor and unoccupied unit operation will not occur.

If the unit is configured to use a sensor for the Space Control Point or if Linkage is active and the space has unoccupied demand, the software point OKFAN will turn on followed by the points TRMCT for air terminal control and PUMP and TOWER to request condenser water flow and temperature control. Approximately 20 to 30 seconds later the SF point will turn ON and then the VFD output SPEED will increase. If unoccupied demand is the reason the fan is on, a control force will appear next to the OKFAN point. Otherwise there should not be a force on that point.

If the fan is running due to unoccupied heating or cooling demand, either the space temperature (if installed), return air temperature or average linkage temperature must rise or drop to within half way between the occupied and unoccupied set points in order for the fan to turn back off.

Enabled by Switching to Local Mode — When the switch is placed in the local mode the ROCC point will indicate enable. If ROCC is ENABLED a software routine will override the occupancy schedule so that TIMECLOCK will also turn on. When ROCC is turned off the TIMECLOCK point will turn off within 60 seconds.

Supply Fan Shutdown — If the unoccupied demand is satis- fied and TIMECLOCK and ROCC are off and disabled, OKFAN will turn off, SF_SFS will turn off, Tower and PUMP will turn off, and then 5 minutes later the SF point will turn off and the VFD speed will go to 0%.

During the 5-minute delay, the cooling and heating routines become disabled. This delay allows a compressor that may have just started to run for its 5-minute minimum on time with the supply fan on. For example, if the staging routine had just started Compressor 3 at the time the OK_FAN point changed to OFF, the cooling routine would become disabled and com- pressors 1 and 2 would shut off right away. Compressor three would continue to run for its minimum on time of 5 minutes. The fan continues running until all compressors meet the minimum on time and run with a load, preventing them from shutting down due to a safety.

Supply Fan operation with Optional Bypass (50XJ) — If the optional VFD Bypass is installed and the Bypass switch has been turned to Bypass, and the access panel is in place, the software point Bypass access panel secure BB_SAFE has been turned to ON, and the unit operation switch has been placed back in local or remote, then the bypass start stop point BPS_S will follow the SF point when it turns on and off. The terminal open point TRMOP will go on with the TRMCT point before the fan starts.

COMPRESSOR COOLING — If the fan is on and there is no demand for Heat, the equipment mode (MODE) will be COOL, and Cooling (COOLOK) will switch to ENABLE.

If the unit is configured for variable flow the Reverse/Head Pressure CTRL valve will open (otherwise it will already be open), and if there is condenser water flow (CDWF is YES), then the Fan + Condenser water flow point will become TRUE and the Compressor Cooling (COMRES) point will switch to Enable.

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Contents Controls Operation Troubleshooting Page Control Inputs and Outputs SW2 SW3 SW1Communication Cable Recommendations Manufacturer Part NumberWhen the unit is off, both valves are closed Field Terminal Blocks for 50XJ Unit Space Temperature Sensor Typical Wiring 33ZCT55SPT LID Function Keys Operative KeysNumeric Keys Operative USE KeysOmnizone Vpac Quick Access Chart KEY Algo Stat Hist Srvc Alrm SETOmnizone Page SETPT01 Controller Set Points OMNIZONESETPT02Controller Hardware Points Configuration ParametersSoftware Points Operation Page Page RUN Keys and Functions for 50XJ VFD VFD Non-Trip Messages for 50XJ UnitVFD Trip Messages for 50XJ Unit KEY Operaton LED Message Explanation VFD Mode Summary for 50XJ UnitDown 50BV VFD Display Non-Trip Messages for the 50BV VFD Trip Messages for 50BV VFDOL1 OL2Epho EPH1Error Communication Problem Possible Causes Remedies Code Forcing an Input or Output Run Test TroubleshootingClearing a Forced Input or Output Alarms Displayed at Unit LID Compressor MUX Board Voltages Comp Volts Range50BVJ,K Low Voltage Schematic Unit Wiring50BVJ,K High Voltage Schematic 50BVW,X Low Voltage Schematic TRANS-3 24VAC BLU50BVW,X High Voltage Schematic 50BVJ,K,W,X Field-Installed Low Voltage Schematic PCB2 J150BVJ,K Field-Installed Low Voltage Schemtic 3 4 5 6 750BVW,X Field-installed Low Voltage Schematic Field WiringRocc AquaSPT Bpss50XJ Low Voltage Control Wiring LOW Voltage Control Wiring50XJ 115V Control Wiring BLK VIO Switch Settings50XJ Power Wiring Power Wiring50BV,XJ Accessory Control Module PCB3 Schematic PCB3Heat CdwfsHRN IFMDescription Value Units Status Force Name Numcmp RsetrtoCdwf 0=NO,1=YES Cdfwswt Econ 0=NO,1=YES Ewtsns EwtrstDescription Value Units Name Pntname SETPT09SENSDI00 SETPT00High Conversion Endpoint 309.77 Comparison Point OMNIZONEDSALM02 Phase Protection Monitored Input Point OMNIZONEDSALM05 Fire alarm Monitored Input Point OMNIZONEDSALM08 Compressor 1 Alarm Monitored Input Point DISCRO00 LINK09 OMNIZONEINTLK02 Ok to Cool Discrete Output Point VOLTI00 SETPT03NTFC00 HCVAV01OMNIZONELMALM02 Entering WaterTemp Monitored Input Point DOW1 DOW2DOW3 DOW4Maintenance Screens False CcvvrfADAPT03 LMALM03ADAPT02 ADAPT01Eeprom RAMDodxrf Description Value Units Status Force Name ANCTL01 CCVAV01LMALM02 Resched TaskstatTasktimr Exetime

50XJ064-104 specifications

The Carrier 50XJ064-104 is a high-efficiency rooftop air conditioning system designed to deliver exceptional cooling and heating capabilities for diverse commercial applications. One of the standout features of this model is its robust cooling capacity of 64,000 BTUs, making it suitable for mid to large-sized spaces. The 50XJ064-104 is engineered using advanced technologies to ensure energy efficiency and reliable performance, contributing to reduced operational costs and environmental sustainability.

One of the primary technologies employed in the Carrier 50XJ064-104 is the high-efficiency scroll compressor. This component plays a pivotal role in optimizing energy usage while delivering consistent cooling output. The system also incorporates an economizer that allows for enhanced energy savings by utilizing outdoor air for cooling when conditions are favorable. This not only decreases reliance on the compressor but also improves indoor air quality.

The microprocessor-based controls in the 50XJ064-104 provide precise temperature regulation, ensuring optimal comfort levels in various applications. These controls allow for easy programming and can be integrated into building management systems for centralized oversight. Additionally, the unit features a built-in fault detection and diagnostic system that aids in identifying potential issues before they escalate, minimizing downtime and maintenance costs.

The Carrier 50XJ064-104 is designed with durability in mind. It features a weather-resistant cabinet, designed to withstand harsh outdoor conditions and prolong service life. The high-quality insulation within the unit not only enhances energy efficiency but also minimizes noise levels, making it an ideal choice for urban environments where sound control is critical.

Another important characteristic is its environmentally friendly R-410A refrigerant, which has a lower impact on ozone depletion compared to older refrigerants. This aligns with Carrier's commitment to creating sustainable HVAC solutions that comply with current environmental regulations.

Overall, the Carrier 50XJ064-104 stands out for its combination of efficiency, advanced technologies, and durable construction. Whether for commercial buildings, retail spaces, or industrial applications, this rooftop air conditioning unit is designed to provide reliable performance and comfort year-round.
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