Sterling 30RA010-055 Compressor and Unit Protective Devices, Check Unit Safeties, Switch Fixed

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Fig. 34 — Mounting Locations for TXV Sensing Bulb

TXV SENSOR

LOCATION

TXV SENSOR

LOCATION

Fig. 34 — Mounting Locations for TXV Sensing Bulb

The amount of capacity reduction achieved by the mini- mum load valve is not adjustable. The total unit capacity with the minimum load valve is shown in Table 7.

PRESSURE RELIEF DEVICES — All units have one pres- sure relief device per circuit located in the liquid line which re- lieves at 210 F (100 C).

Compressor and Unit Protective Devices

MANUAL STARTER — There is one manual starter per compressor in each unit. It protects the compressor(s) against overloading, locked rotor conditions, and primary single phas- ing. If the manual starter trips, determine the cause and correct it before resetting.

Manual starters are factory set; field adjustment should not be required. Manual starters are also factory installed for each condenser fan motor and factory-installed chilled water pump.

NOTE: Two-speed condenser fan motors on sizes 010-018 and 032-040 have manual starters so that the motor is protected while running in both low and high speed modes. Refer to Appendix B for factory settings.

COMPRESSOR INTERNAL THERMAL PROTECTION — All models include internal compressor protection. Models using the SM110 compressor (015 50 Hz and 018 60 Hz) have internal line break overloads. All other compressor models have internal discharge temperature thermostats that are wired in series with the compressor high pressure switch in the com- pressor motor junction box. The thermostat opens and shuts off the compressor if the discharge gas temperature exceeds 275 F (135 C). The thermostat will automatically reset when the tem- perature drops below a preset level, however, the control mod- ule will keep the unit locked off until the alert condition is reset.

Check Unit Safeties

HIGH-PRESSURE SWITCH — A high-pressure switch is provided to protect each compressor and refrigeration system from unsafe high pressure conditions. See Table 32 for high- pressure switch settings.

The high-pressure switch is mounted in the discharge side of each compressor. A snubber is provided between the com- pressor discharge manifold and the high-pressure switch to pre- vent pressure pulsations from damaging the switch.

The high-pressure switch is mounted in the discharge line of each compressor. If an unsafe, high-pressure condition should exist, the switch opens and shuts off the affected compressor. The compressor feedback signal to J9 of the MBB then opens causing an alert condition. The MBB prevents the compressor from restarting until the alert condition is reset. The switch should open at the pressure corresponding to the appropriate switch setting as shown in Table 32.

Table 32 — Factory Settings, High-Pressure

Switch (Fixed)

UNIT

CUTOUT

CUT-IN

Psig

kPa

Psig

kPa

 

30RA

426 ± 7

2937 ± 48

324 ± 20

2206 ± 138

Clear the alarm using the Scrolling Marquee display as de- scribed on page 42. The unit should restart after the compressor anti-short-cycle delay, built into the unit control module, expires.

PRESSURE TRANSDUCERS — Each refrigerant circuit is equipped with a suction and discharge pressure transducer. The transducers are NOT the same part number. The discharge pressure transducer is the universal pressure transducer while the suction pressure transducer is a discrete low pressure trans- ducer. These inputs to the MBB are not only used to monitor the status of the unit, but to also maintain operation of the chill- er within the compressor manufacturer's specified limits. The input to the MBB from the suction pressure transducer is also used to protect the compressor from operating at low pressure conditions. In some cases, the unit may not be able to run at full capacity. The control module will automatically reduce the ca- pacity of a circuit as needed to maintain specified maximum/ minimum operating pressures.

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Contents SAFETY CONSIDERATIONS CONTENTS GENERALSterlco Comfort Network SCN Interface — MAJOR SYSTEM COMPONENTSControl Module Communication Table 1 — Unit SizesTable 2 — Thermistor Designations Table 3 — Status SwitchesTable 5 - SCN Communication Bus Wiring Table 4 - Output RelaysLEGEND FOR FIG. Page Page Fig. 3 — Wiring Schematic 30RA010-018 30RA010-018AQUA SNAPSEE NOTE SEE NOTE AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICFig. 3 - Wiring Schematic 30RA010-018cont Fig. 4 - Wiring Schematic 30RA022-030 30RA022-030AQUA SNAPFig. 4 - Wiring Schematic 30RA022-030cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICFig. 5 — Wiring Schematic 30RA032-040 30RA032-040AQUA SNAPFig. 5 — Wiring Schematic 30RA032-040cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICFig. 6 — Wiring Schematic 30RA042-055 30RA042-055AQUA SNAPFig. 6 — Wiring Schematic 30RA042-055cont AQUA-SNAPLOW VOLTAGE CONTROL SCHEMATICREMOTE CONTACT SW1 OFF ENABLE OFF SW2 ON Fig. 7 — Main Base BoardESCAPEENTER MODEFig. 9 — Typical Space Temperature Sensor Wiring Fig. 11 - Energy Management Module CEPL130351100/100 Fig. 12 — Deadband Multiplier Fig. 14 — 30RA Condenser Fan Sequence Fig. 13 — Operating Envelope forR-22Maneurop Compressor Cooling Set Point Select Table 8 — Control Methods and Cooling Set Points Service Test See Table 11 — Both main powerand control circuit power must be on Fig. 16 — Scrolling Marquee DisplayOptional Factory-InstalledHydronic Package — •Cooler Pump Control CPC Configuration, OPT1 ON Fig. 17 — Dual Chiller Thermistor Location Table 9 — Marquee Display Menu StructureTable 10 — Run Status Mode and Sub-ModeDirectory SUB-MODE Table 12 - Temperature Mode and Sub-ModeDirectory Table 15 — Inputs Mode and Sub-ModeDirectory Table 13 — Pressure Mode and Sub-ModeDirectoryTable 14 — Set Point and Sub-ModeDirectory KEYPAD Table 16 — Outputs Mode and Sub-ModeDirectorySUB-MODE DISPLAYITEM SUB-MODEKEYPAD DISPLAYITEM SUB-MODEKEYPAD DISPLAYTable 18 — Time Clock Mode and Sub-ModeDirectory PER.3 SUB-MODE Table 20 — Alarms Mode and Sub-ModeDirectory Table 19 — Operating Mode and Sub-ModeDirectoryKEYPAD ENTRY SUB-MODEITEM DISPLAYRSET DISP Table 23 — Operating Modes Table 24 — Example of Reading and Clearing Alarms Table 25A — 4-20mA ResetTable 26B — Configuring Return Temperature Reset Fig. 19 — Outdoor-AirTemperature Reset Fig. 18 — Standard Chilled FluidTemperature Control — No Reset Fig. 20 — Space Temperature ResetFig. 21A — 4- to 20-mADemand Limiting Fig. 21B — Cooling Set Point 4 to 20 mATROUBLESHOOTING Table 27 — Configuring Demand Limitand fluid tubing Table 28 — TroubleshootingRecommended that system be filled with an appro Fig. 22 — Component Arrangement — 30RA010-030 FU — Fuse GND — GroundFig. 23 — Component Arrangement — 30RA032-040 FU — Fuse GND — GroundFig. 24 — Component Arrangement — 30RA042-055 FU — Fuse GND — GroundNOTES LEGEND Table 29 — Alarm and Alert Codes Table 29 - Alarm and Alert Codes cont Table 29 — Alarm and Alert Codes cont ALARMTable 29 — Alarm and Alert Codes cont ALARMTable 29 — Alarm and Alert Codes cont ALARMTable 30 - Unit Torque Specification SERVICECompressor Replacement Refer to Fig Electronic ComponentsFig. 29 — Compressor Location — 30RA010-030 Fig. 28 — Compressor WiringFig. 27 — Typical Compressor Mounting — All Sizes Fig. 30 — Compressor Location — 30RA032-055Condenser Section and Coils Table 31 - Oil ChargeFig. 32 — Condenser-FanMounting Fig. 31 — 30RA Access PanelsCheck Refrigerant Feed Components Fig. 33 — Condenser-FanPosition Standard FanCompressor and Unit Protective Devices Table 32 — Factory Settings, High-PressureSwitch Fixed Check Unit SafetiesCOOLER FREEZE-UPPROTECTION TEMP TEMP For Thermistor T10 For Thermistor T10 Fig. 36 — Thermistor Connections to Main Base Board, J8 ConnectorFig. 35 — Fluid-SideTemperature Sensors T1 and T2 PROGRAMMING Mode •P51: SOFTWARE version Table 37 - Fault Codes•P50: FAULT HISTORY — Last 8 faults PARAMETERS Table 39 — Replacement Modules PRE-START-UP MAINTENANCEMinimum Loop Volume System CheckOperating Limitations Standard 30RA Units OPERATION SEQUENCETable 41 — Temperature Limits for CIRCADIO Circuit A Discrete Inputs/Outputs APPENDIX ASCN Tables A_UNIT General Unit Parameters CIRCA_AN Circuit A Analog ParametersOPTIONS Unit Parameters CIRCBDIO Circuit B Discrete Inputs/OutputsCIRCB_AN Circuit B Analog Parameters DUALCHIL Dual Chiller Configuration Settings ALARMDEF Alarm Definition TableDISPLAY Marquee Display SETUP BRODEFS Broadcast POC Definition TableOPTIONS1 Options 1 Configuration OPTIONS2 Options 2 ConfigurationSETPOINT SCHEDOVR Timed Override SetupRESETCON Temperature Reset and Demand Limit MAINTENANCE ALARMS: Maintenance DisplayUNIT CURRMODS: Maintenance Display DUALCHIL: Maintenance DisplayLEARNFNS Maintenance Display LOADFACT: Maintenance DisplayPM-STRN Maintenance Display PM-COIL:Maintenance DisplayPM-PUMP:Maintenance Display RUNTEST: Maintenance Display VERSIONS: Maintenance Display STRTHOUR Maintenance DisplayTESTMODE: Maintenance Display WSMDEFME: Maintenance Display AND MANUAL STARTERS FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMPAPPENDIX B AND MANUAL STARTERS cont FACTORY SETTINGS FOR COMPRESSOR, FAN, PUMPAPPENDIX C DataPort, DataLink, BAClink Object DefinitionOPTIONS SETPOINTII. Preliminary Equipment Check START-UPCHECKLIST FOR 30RA LIQUID CHILLERRemove and use for Job File I.Project Information Design InformationIII. Unit Start-Up Start and Operate Machine. Complete the FollowingCL-3 CL-4 Record Software Versions MODE — RUN STATUSCOMMENTS III.Unit Start-Upcont UNIT Configuration SettingsOPTIONS1 Options Configuration III.Unit Start-Upcont OPTIONS2 Options ConfigurationRSET Reset Configuration Settings CL-6SETPOINT SLCT Setpoint and Ramp Load ConfigurationIII.Unit Start-Upcont CL-7Service Test Mode and Sub-ModeDirectory III.Unit Start-Upcont
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