Sterling 882.00722.00 manual Extruder Pulse Count Method, Percent of hopper Method Default

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Extruder Pulse Count Method

This method updates the weight every “Number of Pulses for Calculation” detected by the extruder proximity switch. This is not the most automated method of the 3 choices, but has it’s advantages. If you are using an unusually large extruder and running it in production at a very low speed then this method works best because the snapshot is taken at the same rotational position of the extruder and eliminates errors in measurement that are caused by the pulsing of the feed throat.

Percent of hopper Method (DEFAULT)

This is the most automated and responsive of the 3 choices. The snapshot sample is based on the “Percent of Hopper for Calculation” setting. The smaller you make this setting the quicker the hopper will update. If this value is set too small then you will be measuring the instantaneous throughput of the feed throat instead of the average loss-in-weight. The average consumption at the feed throat always equals what is coming out at the die. However, the instantaneous feed throat usage is not equal to the usage at the die. This is due to the pressure barrier sections and design of your extruder. The goal of the GH system is to accurately control and measure what is coming out the die and not to respond to nuance changes at the feed throat. It is not recommended that you reduce this setting unless consulting engineering or service and you fully understand this feature.

Full Hopper Method

This is the most stable of all 3 choices. Upon reloading a weight snapshot and time are used to calculate the overall usage since the last reload. This is also the least responsive setting.

WTP/RPM Filter

When switching between the 3 methods you need to understand the sample time and configure the “WTP/RPM Filter” appropriately. A good example of this is that by default the hopper is configured to reload at 50% (keeps material in the vertical section of the hopper), sample in “Percent of Hopper Method” at 20%, and uses a filter of “9”. If it is desired to switch to the “Full Hopper Method” then you don’t need a filter of “9”. A filter of “9” uses 10 points. At a sample of “20%” you get 2 samples per reload. It would therefore take 5 reloads to fill the analyzer upon starting the line. After that the measurement will be updated with each and every 20%. When switching to the “Full Hopper Method” you only need a filter of “4” to achieve the same time frame of samples, but the response will be much dampened to any oscillation or error in measurement. If using the “Extruder Pulse Count Method” then you must do the math to determine what sample time frame you need.

Steady WTP/RPM Window

No matter which method you chose the analyzer compares the series of measurements to the “Steady WTP/RPM Window” percent to determine if the measurements are stable. If this is set too small the system might never give you a “Steady Process” indication. If set too big then the system could respond to nuance changes in the loadcell and cause an erratic response in your control system. When set properly the weigh hopper can be hit with a hammer (not

Chapter 7: Appendix

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Contents GH-M Rate Monitor Allen-Bradley Controller Write Down Your Serial Numbers Here For Future Reference Shipping Info Unpacking and InspectionEvent of Shipping Damage If the Shipment is Not CompleteReturns Warranty ReturnsCredit Returns Table of Contents Maintenance How to Use This Manual SafetySafety Symbols Used in this Manual Safety Tags and Warning Labels Description Follow all Safety Codes Wear Safety Glasses and Work GlovesGeneral Responsibility ResponsibilityOperator Responsibility Remember Maintenance Responsibility Reporting a Safety DefectAccessories Functional DescriptionModels Covered in This Manual General DescriptionCustomer Service Mechanical Features Typical Features and ComponentsController Features System Component Description Extruder Inductive Proximity SwitchSurge Hopper Open Weigh HopperFunction Typical GH-M Operator Screen Operator Screens Common to all GH Systems Typical Setup Screens Optional Components Ethernet ModulePneumatic Slide Gate below surge hopper Safety FeaturesLow Level Proximity Sensors Installation Mechanical InstallationMounting Configurations Uncrating the EquipmentElectrical Connections Machine MountPneumatic Connections Weigh Hopper Installation Initial Set-upMechanical Set-up Extruder RPM connectionFinal Connections Display Startup ScreenController Set-up GH Controller Menu Structure Recipe Page StartGH Calibration Weigh Hopper Load Cell CalibrationDisplay Calibration Menu Screen Hopper Size Setup WTP/RPM CalibrationExtruder Setup Hauloff Setup and Encoder CalibrationAlarm Setup Network SetupSetting Date and Time PanelView Configuration ScreenOperation GH-M Operation ProceduresOperator Displays GH Full Control Operation Procedures Typical Operator Screen for GH Full Control systemGH-F Gravimetric Feeder Operation Procedures Common Screens Typical Manual Control Operator ScreenAlarms with Descriptions Alarm FlagsPrint Inventory Maintenance Preventative Maintenance SchedulePreventative Maintenance Corrective MaintenanceElectrical Internal Components of the Control PanelInput Signals to Programmable Controller Output Signals from Programmable ControllerTroubleshooting IntroductionProblem Corrective action ProblemWarranty and Spare Parts Warranty SpecificationsWarranty Restrictions Warranty LiabilitiesCustomer Responsibilities Annex B InformationTypical Surge Hopper Assembly Parts List Passwords Addendum Service Supervisor InformationProgrammable Settings Typical Engineering Only Setup Screen Percent of hopper Method Default Extruder Pulse Count MethodFull Hopper Method WTP/RPM FilterMax Allowed WTP/RPM Mechanical Options ScreenDiagnostics Screen Typical Analog Options Analog options screenCustomer Setup Menu Password ProtectionAlarm Log UnitsBelow are the items that can be accessed for the GH Hopper Allen-Bradley Communications ManualAppendix Reload TOO Long Fixed Decimal Explanation Parts Department Service Department Sales DepartmentContract Department
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