Emerson 20/20 service manual Operational Differences from Single Screw, Auto Load Timer

Page 117

Section 25 • Cool Compression Control

•Auto Load Timer

•This timer defines the maximum time that the Auto Load operation will be engaged. After the timer expires, Auto Load will be disengaged.

•Auto load will be disengaged when one of the follow- ing conditions occur;

•Pressure ratio reaches a value of 2.0 or greater.

•Compressor has been running for 10 minutes (defined by Auto Load Timer).

•Suction pressure setpoint has been reached.

Suction Oil Injection Setting

•In order to maintain adequate lubrication during low pressure ratio conditions, the Suction Oil Injection (SOI) solenoid is turned ON and the capacity of the compressor is reduced.

•The SOI solenoid will cycle ON and OFF based on the pressure ratio across the compressor.

•SOI Solenoid ON

•Defines the Pressure ratio value at which SOI is turned ON (default 2.00) (Digital Output Board #1:2).

•SOI Solenoid OFF

•Defines the Pressure ratio value at which SOI is turned OFF (default 2.04) (Digital Output Board #1:2).

•SOI Load Limit

•Defines the capacity slide position at which the compressor capacity slide will unload to if pressure ratio falls below “SOI Solenoid ON” set- point. This setpoint is not active until Auto Load disengages.

•The SOI solenoid will also cycle on if the discharge temperature superheat reaches a value of 5°F (this value is not settable). Generally, anytime the SOI solenoid cycles on, the capacity is limited to the SOI Load Limit setpoint. However, this is not true if the SOI solenoid cycles on based on the discharge tem- perature superheat 5°F rule. If discharge temperature superheat continues to climb and reaches a value of 6°F, the compressor will be inhibited from loading. If discharge temperature superheat still continues to climb and reaches a value of 8°F or more, then the compressor will be unloaded until the superheat drops below 8°F or the capacity has reached the SOI Load Limit setting.

Using a Positioning Valve for Liquid Ammonia Level Control

•A level probe inserted in the oil separator detects liquid ammonia level. Based on the level of the am- monia (0-100%), the level probe sends a directly pro- portional 4-20 mA signal to the Vission 20/20 panel. The positioning valve is then positioned based on the Positioning Valve settings graph shown in Figure 25-

2.Cool Compression Control Functions Screen.

•Looking at the graph, when the compressor starts, the positioning valve placement (Vertical Axis) is de- termined based on the liquid ammonia level that is sensed in the oil separator (Horizontal Axis). It can be seen that as the liquid ammonia level increases (corresponding to a larger mA value), the positioning valve moves towards a closed position.

•The Positioning Valve position (0-100% limits) is de- fined at three distinct levels;

•Start Level (lowest liquid ammonia level - po- sitioning valve at maximum open position).

•Leakage (normal operating position and am- monia level).

•Overfill Leakage (highest liquid ammo- nia level–positioning valve at minimum open position).

•Liquid ammonia levels are defined at four distinct lev- els (4-20ma limits);

•Start SP (minimum liquid ammonia level in separator – the positioning valve is maximum open).

•Linear SP (minimum level of liquid ammonia for normal operating position).

•Upper SP (maximum level of liquid ammonia for normal operating position).

•Max SP (maximum liquid ammonia level – po- sitioning valve is minimum open position, main- taining some leakage).

•On Alarms and Trips screen, Low Oil Separator Start Temperature, High Filter Diff Start Pressure settings are disabled.

•On Timers screen Oil Level #1 Safety Trip Delay, Oil Level #2 Safety Trip Delay settings are disabled.

Operational Differences from Single Screw

Once the Cool Compression is configured, most setup options available for a single screw are also available for Cool Compression. However, there are significant

Vission 20/20 • Operation and Service Manual •Vilter/Emerson • 35391SC 1.8.5153

25 – 3

Page 116 Page 118
Image 117
Page 116 Page 118
Contents Vission 20/20 micro-controller Page Table of Contents Digital I/O Board Layout Top Status Bar TOCCompressor Sequencing Event List Data Backup List of Tables and Figures END of TOC How to Use This Manual Requirements to Start Compressor Operational Flow ChartsCritical Compressor Run Logic at Compressor Start Compressor Amperage Load LimitingOperational Flow Charts 2 Installation Recommendations Proper Wiring SizingVoltage Source DC signals GroundingMixing Voltages Correct Transformer Wiring Method Wiring MethodsBest Practices Overview Hardware ArchitectureDigital Input/Output I/O Board Description Type Digital I/O 1Refer to -2. Analog Inputs Motor Current Analog InputsAnalog Inputs 1 Digital I/O 2Digital & Analog I/O Boards Layout Analog OutputsDigital I/O Board Layout Analog Inputs 2Digital Output Board Layout Digital Output BoardsDigital Input Board Layout Digital Input BoardsDigital Input-Output Board Layout Digital In-Out BoardsAnalog Input Board Layout Analog Input BoardsAnalog Input Jumper Tables Channel SignalJP-13 JP-14 JP-15 JP-31 Analog Output Board Layout Analog Output BoardsMain Screen Main ScreenTop Status Bar Parameter Bar Unit Start Pop-Up Window Bottom Status Bar Splash Screen Navigation Buttons Menu ScreenMenu Screen Pulse Proportional Control Compressor ControlProportional Band & Setpoint Auto-CycleVFD One-Step Control Method Variable Frequency Drive VFDPumpdown Control Pulldown Control Volume Slide Position Offset Control ModeStop Load and Force Unload Capacity Slide Triggered OutputsLoad Anticipating Oil ControlLiquid Injection Compressor Control Alarms and Trips Setpoints Alarms and TripsAlarms and Trips Compressor Inhibits Safety Failure MessagesFalse Start Timer Setpoints TimersOil Separator Level #2 Safety Trip Delay Timers Blank Scheduling Setpoint Compressor SchedulingCompressor Scheduling Pressure Control Setpoints Compressor SequencingCFM Equipment List 10 4 / Blank Condenser Control Setpoint Condenser ControlStep Control Step Control Screen VFD Settings11 4 / Blank Digital Outputs Service OptionsAnalog Outputs Instruments Calibration Pressure and Temperature InputsRemote Capacity Motor CurrentAnalog Inputs 13 4 / Blank Capacity Slide Valve Potentiometer Slide CalibrationVolume Slide Valve Potentiometer Slide Valve OperationSlide Valve Actuator Calibration for Optical Style Motors Photochopper Command Shaft Rotation Required By Actuator Command Shaft RotationSlide Valve Troubleshooting Guide 1 Slide Valve Troubleshooting GuideSlide Valve Troubleshooting Guide 2 LED Blink Codes and Troubleshooting Guide 1 Slide Valve Actuator Troubleshooting Guide Blink CodePleted. The actuator will not move while this error code LED Blink Codes and Troubleshooting Guide 2Chart Operation Trend ChartTrend Data Storage Trend Setup Screen Setup15 4 / Blank Event list Columns Event List16 2 / Blank Input/Output Screen Input / Output17 2 / Blank Digital Inputs Auxiliary Input / OutputDigital Outputs Control 18 4 / Blank Configuration UnitsTime & Date Communications TouchscreenAnti-Recycle Compressor Sequencing Restart On Power FailureLanguage Model & RefrigerantOptional Function Selection Compressor ControlOil Pump Condenser ControlOil Cooling Motor Current DeviceDigital Inputs Analog Inputs Analog Outputs Configuration 19 10 / Blank Save / Load Data BackupData Backup Migrate Factory Reset20 4 / Blank Checklist MaintenanceLog ChartApply User AccessManage Accounts LoginScreen Security Levels Security Access Levels22 4 / Blank Help Screen Screen FeaturesVersion Pop-Up Screen Twin Screw Control Screen Twin Screw ControlOperation Cool Compression Control Screen Cool Compression ControlCool Compression Control Functions Screen Control FunctionsOperational Differences from Single Screw Auto Load TimerCool Compression Control

20/20 specifications

Emerson 20/20 is an advanced platform designed for real-time data analytics, visualization, and operational optimization in industrial settings. This robust solution aims to empower organizations by providing actionable insights derived from their operational data, enabling enhanced decision-making and improved efficiency.

One of the standout features of Emerson 20/20 is its ability to integrate seamlessly with various sources of data, whether structured or unstructured. It consolidates information from different systems, such as historians, control systems, and ERP software, allowing users to gain a comprehensive view of their operations. This integration capability is crucial for businesses looking to maximize their data utilization without being confined to a single data source.

The platform employs powerful analytics tools that utilize machine learning and artificial intelligence technologies. These tools are designed to automatically identify patterns, anomalies, and trends in real-time. By leveraging predictive analytics, Emerson 20/20 helps organizations forecast potential issues before they escalate, allowing for proactive maintenance and minimizing downtime.

Emerson 20/20 also features user-friendly visualization dashboards, which provide customizable views tailored to individual user roles. This means that whether you are a plant manager, a process engineer, or an executive, you can access relevant data that speaks directly to your needs. These dashboards facilitate easier understanding of complex data sets, promoting informed decision-making across the organization.

One notable characteristic of Emerson 20/20 is its adaptability and scalability. Businesses of all sizes can implement the platform and scale its features according to their needs. This flexibility ensures that both small operations and large enterprises can derive value from the solution, making it an attractive option for various industries.

Additionally, the platform is designed with cybersecurity in mind, ensuring that data integrity and confidentiality are maintained. This aspect is increasingly important as industries become more interconnected and target more sophisticated cyber threats.

In summary, Emerson 20/20 stands out as a powerful tool for organizations seeking to harness their operational data effectively. With its advanced analytics capabilities, seamless integration, customizable visualization, and scalable design, it offers a comprehensive solution to optimize industrial performance and support data-driven decision-making. As businesses continue to navigate the complexities of modern operations, Emerson 20/20 provides the insights necessary to stay competitive and responsive to changing market demands.
Top Page Image Contents