HP A0554832 Low Pressure Cutout, Oil Pressure Safety Switch, Fan Cycling Switch, Pressure Switch

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Low Pressure Cutout

This electro-mechanical cutout device opens the compressor control circuit if refrigeration system compressor suction pressure drops below 15 psi. It automatically resets when refrigerant suction pressure reaches 30 psi.

Note: The low pressure cutout is an automatic reset device typically mounted on the compressor suction line inside the mechanical cabinet. Call a refrigeration service technician to analyze the problem and reset the control.

Oil Pressure Safety Switch

This mechanical cutout device is installed on chillers built with semi-hermetic compressors that have oil pumps. A differential pressure switch monitors the difference between crankcase pressure and oil pump pressure.

If the pressure drops to an unsafe level for more than two minutes, the switch opens the control wiring circuit, shutting off the compressor and turning the light on, but the pumps will continue running.

Note: The oil pressure safety switch is a manual reset device. Call a refrigeration

service technician to analyze the problem and reset the control.

Fan Cycling Switch

Air-cooled models only. 5 hp and 7.5 hp models have one fan. The fan cycling switch turns on the fan when the discharge pressure in the condenser reaches 300 psi and turns it off when the pressure drops below 190 psi.

10 hp to 30 hp models have two fans. One fan runs continuously every time the compressor operates. The second fan turns on when the discharge pressure in the condenser reaches 275 psi and turns off when the pressure drops below 200 psi.

Pressure Switch

2 hp and 3 1/2 hp models have a pressure switch cutout device mounted in the process piping. The switch shuts down the chiller if it senses that the water/glycol pressure through the evaporator has dropped below an acceptable level. The pressure switch opens the control circuit, shuts down the pumps, and shuts off the chiller.

Flow Switch

5 hp to 40 hp models only. The flow switch cutout device, mounted in the process piping, shuts down the chiller if senses that the water/glycol flow rate through the evaporator has dropped below an acceptable level. The flow switch opens the control circuit and shuts down the pumps and the chiller.

Remote Start/Stop Interlock

An additional contact is provided to allow the remote starting or stopping of the chiller. To use this feature, remove the jumper between terminals X1 and 1, and supply a switch or dry contact interlock connected in series between these two terminals. Refer to the schematic inside the control enclosure door.

2-40 HP Portable Chillers

Chapter 2: Functional Description

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Contents Hp Portable Chillers Shipping Information Table of Contents Operation HP Portable Chillers How to Use This Manual SafetySafety Symbols Used in this Manual Responsibility Wear Safety Glasses and Work GlovesModels Covered in This Manual Functional DescriptionChilled Water Circuit General DescriptionRefrigeration Circuit Mechanical Features Standard FeaturesOther Mechanical Features Refrigeration Features Electrical FeaturesController Features Other FeaturesHigh/Low Thermostat Control Safety Devices and InterlocksCrankcase Heater High Pressure CutoutFan Cycling Switch Oil Pressure Safety SwitchPressure Switch Flow SwitchOptional Features Mounting Features Optional Pump Amperages Voltage Construction Full Load Amps Uncrating InstallationElectrical Connections Bypass Valve Considerations Process Water ConnectionsGalvanic Corrosion Considerations Water Treatment ConsiderationsWater-Cooled Chiller Condensers Condenser ConsiderationsAir-Cooled Chiller Condensers Remote Air-Cooled Chiller Condensers Page Equivalent Length in Feet for Valves and Fittings Refrigerant Charge Determination Chiller Condenser Charge Field Installed Piping ChargeChecking Motor Direction Three-Phase CompressorsWater Pumps Condenser FanPart Number Description Water ReservoirEthylene Glycol and Propylene Glycol Curves Automatic Water Make-Up Option Initial Start-Up E5CK Controller Indicator Name Description Panel Buttons, Indicator Lights, and SwitchesOperation Microprocessor ControllersSterlco 2000 Controller Indicator Name Description Indicator Name Description2000 Graphic Panel See on Indicator Name DescriptionIndicator Name Description With Sterlco 2000 Controller Typical Graphic Panels With E5CK ControllerAuto-Tuning Setting the Process Water TemperaturesStart-up Optional CommunicationsProgramming the Electronic High/Low Thermostat Thermostat Buttons Indicator Name DescriptionSelect Fahrenheit or Celsius Stage 2 High Temperature ProtectionStage 1 Freeze Protection Filter Cleaning MaintenanceLubrication Maintaining the Evaporator Maintaining the CondenserEvaporator Process Piping Y-Strainer Air- and Remote Air-Cooled ChillersPreventative Maintenance Service HP Portable Chillers Troubleshooting TroubleshootingHP Portable Chillers Troubleshooting Appendix WarrantyTechnical Assistance Service DepartmentParts Department Sales DepartmentHp and 3 1/2 hp Air-Cooled Portable Chillers Drawings and SpecificationsHp and 7.5 hp Air-Cooled Portable Chillers Hp and 15 hp Air-Cooled Portable Chillers 20 hp, 25 hp, and 30 hp Air-Cooled Portable Chillers Nominal Condenser water Nominal cooling Water Com Hp and 3.5 hp Water-Cooled Portable ChillersIn. NPT Height Width Depth Lbs Hp and 7.5 hp Water-Cooled Portable Chillers Hp and 15 hp Water-Cooled Portable Chillers 20 hp, 25 hp, and 30 hp Water-Cooled Portable Chillers Hp and 40 hp Water-Cooled Portable Chillers Hp and 7.5 hp Remote Air-Cooled Portable Chillers Nominal cooling Com Refrigeration Power in amps e12.8 17.3 748Nominal cooling Com Refrigeration Hp and 15 hp Remote Air-Cooled Portable ChillersPres Nom Connections 15.0 40.9 34.0 74.7To/from No tank Tank, to/from Height Width Depth Lbs Hp through 40 hp Remote Air-Cooled Portable Chillers‘A’in ‘B’in ‘C’in ‘D’in ODSin Remote Condenser Assembly ModelsHertz Pump Curves Pump Curves, Flow, and Pressure ConsiderationsDWG. No. S0554823 Calculating Chiller Nominal Flow and Pressure to Process Water Pressure Drop TablesRecirc. power Flow Rate ∆ pressure Gpm Lpm Psi KPa Recirculation Pump SpecificationsFlow and Pressure Considerations Configuration a Remote Air-Cooled Chiller ConfigurationsConfiguration B Configuration C Typical Ductwork for Air-Cooled Chillers Central and Gravity Return Piping with Standpipe Diagram Piping DiagramsTypical Piping Schematic, 2 and 3 1/2 hp Models HP Portable Chillers Appendix HP Portable Chillers Appendix Typical Piping Schematic, 5 hp through 40 hp, No-Pump Models HP Portable Chillers Appendix Time-delay Relays Disconnect Switch Optional Electrical SchematicsTypical Electrical Subpanel Speed FusesTypical Electrical Schematic, 2 hp and 3 1/2 hp Models A0554815 Typical Power Wiring Schematic, 5 hp through 40 hp ModelsHP Portable Chillers Appendix DWG A0554931 DWG A0562343 DWG A0562435 Typical Wiring Schematic, 35 hp and 40 hp Models with Pump DWG A0562434
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