Sterling 882.93092.01 manual Standard Features, Mechanical Features

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differential” value the controller will enable the compressor; if equipped with two compressors the controller will enable the one with the least amount of hours. The second compressor will be enabled if the leaving fluid temperature remains above the setpoint plus the “compressor on differential” value for more than 60 seconds.

The hot gas valve is designed to trim the load of one compressor and will modulate in order to meet the desired leaving fluid setpoint via a PID algorithm. After the compressor starts, the hot gas valve is allowed to modulate. The compressor will shut off if the leaving fluid temperature drops below the “compressor off differential” and the hot gas valve is at 100% for the “compressor off delay” time. The hot gas will reset to 0% when the compressor is off. There is a “compressor anticyle” timer that will delay the time between compressor starts to prevent short cycling of the compressor. This is a start to start timer set at 5 minutes. For example, if the compressor has been running for 5 minutes and shuts off, then the compressor can start immediately if the demand is there. If it has only been running for 2 minutes, then it would not be able to start again for 3 minutes.

For a unit with two compressors, the second compressor or lag compressor starts when the lead compressor is on, the hot gas is at 0%, and the leaving fluid temperature is above the setpoint plus the “compressor on differential”. There is also an adjustable “lag compressor on delay” timer. Before starting either compressor, the compressor with the least amount of runtime hours is considered the lead compressor and the first to start. When both compressors are running, the compressor with the most hours is considered the lead compressor and is the first to stop. The lead compressor will shut off if the leaving fluid temperature drops below the “compressor off differential” and the hot gas valve is at 100% for the “lead compressor off delay” time. The compressor anti-cycle timers are active with the two compressor units.

There will be two PID controls running simultaneously for determining the position of the hot gas valve. One PID output will be based on leaving fluid temperature and the other based on a minimum saturated suction temperature for freeze protection. The hot gas valve position will be determined by which output is greater. If it is controlling to the saturated suction temperature to prevent freezing, a warning will display on the screen that the hot gas is in this mode. Once the control goes back to setpoint control, the warning will disappear. The saturated suction temperature is calculated from the suction pressure and the type of refrigerant.

The discharge pressure is controlled using an analog output signal to drive a fan for air- cooled units or a water regulating valve for water-cooled units. The output signal is determined from a PID algorithm using a discharge pressure transducer as the process variable. The VFD or water regulating valve is controlled from the analog output to an adjustable discharge pressure setpoint. The analog output starts at the initial “discharge pressure start” % for a given time delay (discharge pressure hold). After the time delay, it will control to the discharge pressure setpoint via the PID control. There is also a setting to control the discharge pressure to the most efficient value.

2-3 Standard Features

Mechanical Features

Compressor – Hermetic scroll compressors.

Evaporator – Stainless steel copper brazed plate evaporators.

GP Series Portable Chillers

Chapter 2: Functional Description

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Contents GP Series Portable Chillers Shipping Information Table of Contents Chapter Troubleshooting How to Use This Manual SafetySafety Symbols Used in this Manual  Wear Safety Glasses and Work Gloves ResponsibilityGeneral Description Functional DescriptionModels Covered in This Manual Typical ApplicationsChilled Water Circuit Refrigeration Circuit System ControlStandard Features Mechanical FeaturesElectrical Features Refrigeration FeaturesOther Features Safety Devices and InterlocksController Features Crankcase HeaterHigh Pressure Cutout Flow Switch Optional FeaturesRemote Start/Stop Interlock Mounting Features Uncrating InstallationElectrical Connections Process Water Connections Bypass Valve ConsiderationsCondenser Considerations Galvanic Corrosion ConsiderationsWater Treatment Considerations Water-Cooled Chiller CondensersTypical GP20-50 Water Cooled Condenser Connections Air-Cooled Chiller CondensersRemote Air-Cooled Chiller Condensers Towards the condenser GPRC-40 GPRC-105 Discharge Line Sizing Refrigerant Charge Determination Remote Condenser Configurations Water Pumps Three-Phase CompressorsChecking Motor Direction Condenser FanWater Reservoir Part Number DescriptionSuggested Overhead Piping Configuration Pump Automatic Water Make-Up Option Initial Start-UpPage Finishing Setup Setting Up Passwords Supervisor Password to complete the security setup Operation Panel Buttons, Indicator Lights, and SwitchesMicroprocessor Controller Main Status Screen Status Screens Operator Setpoints ScreenMain Chiller Status Screen GP Series Portable Chillers Operation Page Access Levels Controller SetpointsGP Series Portable Chillers Operation Menu Screen Operator Setpoints Screen Configuration Settings These configurations are described belowWEB Alarms Optional CommunicationsLubrication MaintenanceFilter Cleaning Maintaining the CondenserMaintaining the Evaporator Preventative Maintenance ServiceEvaporator Process Piping Y-Strainer Troubleshooting Identifying the Cause of a ProblemGP Series Portable Chillers Troubleshooting SC/W System fault GP Series Portable Chillers Troubleshooting Non-Controller Related Issues Problem Possible cause SolutionGP Series Portable Chillers Troubleshooting GP Series Portable Chillers Troubleshooting Returned Material Policy AppendixTechnical Assistance Sales Department Service DepartmentContract Department Specifications Air-Cooled Portable ChillersGPAC-40 GPAC-70 GPAC-105 GPAC-175 Water-Cooled Portable Chillers GPWC-20GPWC-40 GPWC-70 GPWC-105 GPWC-175 Pump Curves, Flow, and Pressure Considerations Hertz Pump CurvesALL 60 Hz ALL 50 Hz ALL 50 Hz Calculating Chiller Nominal Flow and Pressure to Process Remote Air-Cooled Chiller Configurations Double Riser Detail Typical Ductwork for Air-Cooled Chillers Water column = Pascal GP Series Portable Chillers Appendix Piping Diagrams GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix GP Series Portable Chillers Appendix

882.93092.01 specifications

The Sterling 882.93092.01 is an impressive timepiece that exemplifies the perfect blend of artistry and precision engineering. This elegant watch is a testament to the craftsmanship that defines the Sterling brand, making it a sought-after choice for both watch aficionados and casual wearers alike.

One of the main features of the Sterling 882.93092.01 is its exceptional movement technology. This watch is powered by a reliable automatic movement, ensuring accurate timekeeping without the need for battery replacements. The self-winding mechanism harnesses the natural motion of the wearer's wrist, providing a seamless and hassle-free experience.

The design of the Sterling 882.93092.01 is another standout characteristic. The watch features a stainless steel case that provides durability and a sleek aesthetic. The polished finish adds a touch of sophistication, making it suitable for both formal and casual settings. With a diameter that fits comfortably on the wrist, it is designed for effortless wear throughout the day.

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Another notable aspect is the watch's water resistance. The Sterling 882.93092.01 is rated for water resistance, making it suitable for everyday wear, including light swimming and exposure to splashes. This feature enhances the watch’s practicality, allowing it to withstand the rigors of daily life without compromising its integrity.

Finally, the bracelet of the Sterling 882.93092.01 is crafted with comfort and style in mind. It features an adjustable clasp that allows for a customized fit, ensuring that the watch remains secure on the wrist. The combination of high-quality materials and impeccable design makes the bracelet an integral part of the overall charm of the watch.

Overall, the Sterling 882.93092.01 is more than just a timekeeping device; it is a statement piece that showcases exceptional design, reliable technology, and outstanding craftsmanship. Whether worn at special occasions or in everyday scenarios, this watch is bound to impress and stand the test of time.
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