Sterling 30RA010-055 manual Standard Chilled Fluid, Temperature Control — No Reset

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Fig. 18 — Standard Chilled Fluid

2.0F (1.1 C) cooler ∆T and 0° F (0° C) reset at 10.0 F (5.6 C) cooler ∆T. The variable RT.NO should be set to the cooler temperature difference (∆T) where no chilled water tempera- ture reset should occur. The variable RT.F should be set to the cooler temperature difference where the maximum chilled wa- ter temperature reset should occur. The variable RM.DG should be set to the maximum amount of reset desired.

To verify that reset is functioning correctly proceed to Run Status mode, sub-mode VIEW, and subtract the active set point (SETP) from the control point (CTPT) to determine the degrees reset.

Under normal operation, the chiller will maintain a constant leaving fluid temperature approximately equal to the chilled fluid set point. As the cooler load varies, the entering cooler fluid will change in proportion to the load as shown in Fig. 18. Usually the chiller size and leaving-fluid temperature set point are selected based on a full-load condition. At part load, the flu- id temperature set point may be colder than required. If the leaving fluid temperature was allowed to increase at part load, the efficiency of the machine would increase.

Return temperature reset allows for the leaving temperature set point to be reset upward as a function of the return fluid temperature or, in effect, the building load.

Figures 19 and 20 are examples of outdoor air and space temperature resets.

LEGEND

EWT — Entering Water (Fluid) Temperature

LWT — Leaving Water (Fluid) Temperature

Fig. 18 — Standard Chilled Fluid

Temperature Control — No Reset

Demand Limit — Demand Limit is a feature that allows the unit capacity to be limited during periods of peak energy us- age. There are 3 types of demand limiting that can be config- ured. The first type is through 2-stage switch control, which will reduce the maximum capacity to 2 user-configurable percentag- es. The second type is by 4 to 20 mA signal input which will re- duce the maximum capacity linearly between 100% at a 4 mA input signal (no reduction) down to the user-configurable level at a 20 mA input signal. The third type uses the CNN Loadshed module and has the ability to limit the current operating capaci- ty to maximum and further reduce the capacity if required.

NOTE: The 2-stage switch control and 4- to 20-mA input sig- nal types of demand limiting require the Energy Management Module (EMM).

To use Demand Limit, select the type of demand limiting to use. Then configure the Demand Limit set points based on the type selected.

DEMAND LIMIT (2-Stage Switch Controlled) — To con- figure Demand Limit for 2-stage switch control set the Demand Limit Select (DMDC) [Configuration, RSET] to 1. Then

LEGEND

LWT — Leaving Water (Fluid) Temperature

Fig. 19 — Outdoor-Air Temperature Reset

LEGEND

LWT — Leaving Water (Fluid) Temperature

Fig. 20 — Space Temperature Reset

configure the 2 Demand Limit Switch points (DLS1 and DLS2) [Configuration, RSET] to the desired capacity limit. See Table 27. Capacity steps are controlled by 2 relay switch inputs field wired to TB6 as shown in Fig. 4-6.

For Demand Limit by 2-stage switch control, closing the first stage demand limit contact will put the unit on the first de- mand limit level. The unit will not exceed the percentage of ca- pacity entered as Demand Limit Switch 1 set point. Closing contacts on the second demand limit switch prevents the unit from exceeding the capacity entered as Demand Limit Switch 2 set point. The demand limit stage that is set to the lowest de- mand takes priority if both demand limit inputs are closed. If the demand limit percentage does not match unit staging, the unit will limit capacity to the closest capacity stage.

To disable demand limit configure the DMDC to 0. See Table 27.

EXTERNALLY POWERED DEMAND LIMIT (4 to 20 mA Controlled) — To configure Demand Limit for 4 to 20 mA control set the Demand Limit Select (DMDC) [Configura- tion, RSET] to 2. Then configure the Demand Limit at 20 mA (DM20) [Configuration, RSET] to the maximum loadshed val- ue desired. Connect the output from an externally powered 4 to 20 mA signal to terminal block TB6, terminals 1 and 5. Refer to the unit wiring diagram for these connections to the optional/ accessory Energy Management Module and terminal block. The control will reduce allowable capacity to this level for the 20 mA signal. See Table 27 and Fig. 21A.

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Contents SAFETY CONSIDERATIONS CONTENTS GENERALMAJOR SYSTEM COMPONENTS Control Module CommunicationSterlco Comfort Network SCN Interface — Table 1 — Unit SizesTable 3 — Status Switches Table 5 - SCN Communication Bus WiringTable 2 — Thermistor Designations 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 SCHEMATICFig. 7 — Main Base Board ESCAPEENTERREMOTE CONTACT SW1 OFF ENABLE OFF SW2 ON 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 Service Test See Table 11 — Both main power and control circuit power must be onTable 8 — Control Methods and Cooling Set Points 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 Table 16 — Outputs Mode and Sub-ModeDirectory SUB-MODEKEYPAD DISPLAYSUB-MODE KEYPADITEM DISPLAYSUB-MODE KEYPADITEM 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-ModeDirectorySUB-MODE ITEMKEYPAD ENTRY 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. 18 — Standard Chilled Fluid Temperature Control — No ResetFig. 19 — Outdoor-AirTemperature 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 ALARMSERVICE Compressor Replacement Refer to FigTable 30 - Unit Torque Specification Electronic ComponentsFig. 28 — Compressor Wiring Fig. 27 — Typical Compressor Mounting — All SizesFig. 29 — Compressor Location — 30RA010-030 Fig. 30 — Compressor Location — 30RA032-055Condenser Section and Coils Table 31 - Oil ChargeFig. 31 — 30RA Access Panels Check Refrigerant Feed ComponentsFig. 32 — Condenser-FanMounting Fig. 33 — Condenser-FanPosition Standard FanTable 32 — Factory Settings, High-Pressure Switch FixedCompressor and Unit Protective Devices 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 MAINTENANCE Minimum Loop VolumePRE-START-UP System CheckOperating Limitations Standard 30RA Units OPERATION SEQUENCETable 41 — Temperature Limits for APPENDIX A SCN Tables A_UNIT General Unit ParametersCIRCADIO Circuit A Discrete Inputs/Outputs CIRCA_AN Circuit A Analog ParametersOPTIONS Unit Parameters CIRCBDIO Circuit B Discrete Inputs/OutputsCIRCB_AN Circuit B Analog Parameters ALARMDEF Alarm Definition Table DISPLAY Marquee Display SETUPDUALCHIL Dual Chiller Configuration Settings 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 SETPOINTSTART-UPCHECKLIST FOR 30RA LIQUID CHILLER Remove and use for Job File I.Project InformationII. Preliminary Equipment Check 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 OPTIONS2 Options Configuration RSET Reset Configuration SettingsIII.Unit Start-Upcont CL-6SLCT Setpoint and Ramp Load Configuration III.Unit Start-UpcontSETPOINT CL-7Service Test Mode and Sub-ModeDirectory III.Unit Start-Upcont
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