Emerson 848T manual Unscheduled Transfers, Schedule, Device Device Y Device Z

Page 89

Reference Manual

00809-0100-4697, Rev EA October 2011

Rosemount 848T

Figure C-4. Scheduled Data Transfer

Unscheduled Transfers

Figure C-5. Unscheduled Data Transfer

Figure C-4diagrams the method of scheduled data transfer. Scheduled data transfers are typically used for the regular cyclic transfer of process loop data between devices on the fieldbus. Scheduled transfers use publisher/ subscriber type of reporting for data transfer. The LAS maintains a list of transmit times for all publishers in all devices that need to be cyclically transmitted. When it is time for a device to publish data, the LAS issues a CD message to the device. Upon receipt of the CD, the device broadcasts or “publishes” the data to all devices on the fieldbus. Any device that is configured to receive the data is called a “subscriber.”

LAS

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Schedule

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

X, Y, Z

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

DT(A)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

CD(X,A)

 

A

 

 

 

B

 

 

 

 

 

 

 

 

 

 

 

 

C

 

 

A

 

 

 

 

 

 

 

 

 

 

 

D

 

 

 

A

 

 

 

 

 

P

 

 

S

 

 

 

 

 

 

 

 

 

 

 

 

P

 

 

S

 

 

 

 

 

 

 

 

 

 

P

 

 

 

S

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Device X

Device Y

 

 

 

 

Device Z

LAS = Link Active Scheduler

P = Publisher

S = Subscriber

CD = Compel Data

DT = Data Transfer Packet

Figure C-5diagrams an unscheduled transfer. Unscheduled transfers are used for things like user-initiated changes, including set point changes, mode changes, tuning changes, and upload/download. Unscheduled transfers use either report distribution or client/server type of reporting for transferring data.

All of the devices on the FOUNDATION fieldbus are given a chance to send unscheduled messages between transmissions of scheduled data. The LAS grants permission to a device to use the fieldbus by issuing a pass token (PT) message to the device. When the device receives the PT, it is allowed to send messages until it has finished or until the “maximum token hold time” has expired, whichever is the shorter time. The message may be sent to a single destination or to multiple destinations.

LAS

Schedule

PT(Z)

 

X, Y, Z

DT(M)

A

B

C

A

D

A

 

M

 

 

 

M

 

 

P

 

S

P

S

 

P

 

S

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Device X

Device Y

 

Device Z

P = Publisher

S = Subscriber

 

PT = Pass Token

 

M = Message

C-7

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Contents 00809-0100-4697, Rev EA October Reference ManualPage Customer Central National Response Center International Rosemount 848T High Density Temperature Transmitter withPage Table of Contents Section Operation MaintenanceAppendix a TOC-2Section Introduction Safety MessagesProcess leaks could result in death or serious injury Electrical shock could cause death or serious injuryMaintenance of the Rosemount 848T Temperature Transmitter Fieldbus host or configuration toolOverview TransmitterService Support Rosemount 848T Safety Messages Mounting Section InstallationMounting to a Panel with a Junction Box Mounting to a DIN Rail Without an EnclosureAluminum/Plastic Junction Box Stainless Steel Junction Box Mounting to a 2-in. Pipe StandSpur Signal Wiring Devices 1 through WiringConnections Leads and terminalsAnalog Inputs RTD or Ohm InputsThermocouple or Millivolt Inputs Power Supply ConnectorsOhm resistor in the loop when switched to the left Analog InputConnections Power SupplySurges/Transients Grounding Shielded WireTransmitter Enclosure optional 848T Power Supply Sensor Wires Shield ground pointsMA loop Fieldbus busSimulate Enable SwitchesSwitch is not functional SecurityCommissioning Tag TaggingTransmitter Tag Sensor TagUsing Conduit Entries InstallationUsing Cable Glands Section Configuration Standard ConfigurationTransmitter Configuration Custom Configuration Methods Rosemount 848T Typical Profiling Application Common Configurations for High Density ApplicationsFunction BlockMonitoring Application with a Single Selection Measuring Temperature Points IndividuallyMultiple Analog Input or Analog Input Block Configuration Number Parameter Description Block ConfigurationResource Block 00809-0100-4697, Rev EA October Resource Block Parameters Saveconfigblocks SaveconfignowStartwithdefaults FailedenableModes Block ErrorsAutomatic Auto Block is processing its normal background memory checksAlarm Detection Out of Service OOSPlantWeb Alerts Status HandlingFailedmask 00809-0100-4697, Rev EA October Failure AlarmsAlarm Maintenance Alarms/Priority AlarmAdvisory Alarms Recommended Actions for PlantWeb Alerts Alarm Type Active Event Recommended ActionRESOURCE.RBSFTWRREVALL Transducer BlocksRESOURCE.HARDWAREREV, Transducer Block Channel Definitions Transducer Block ErrorsChannel Definitions for the 848T Channel DescriptionTransducer Block Alarm Detection 00809-0100-4697, Rev EA October Block/Transducer ErrorTransducer Block Modes Block outputs reflect the analog input measurementSENSOR2CONFIG SENSOR1CONFIGSENSOR3CONFIG SENSOR4CONFIGChanging the Sensor Configuration in the Transducer Block Transducer Block Sub-Parameter Tables 11. Xderror Sub-Parameter Structure12. Sensorconfig Sub-Parameter Structure 14. Sensorcal Sub-Parameter Structure 13. Sensorstatus Sub-Parameter Structure15. Calstatus Structure 16. Transducer Status Sub-Parameter StructureStructure StructureDual Sensor Status Table Structure Parameter Description 20. Validation Config Sub-Parameter StructureSensor Calibration in the Sensor Transducer Block Rosemount 848T Foundation Operation and MaintenanceFoundation Fieldbus Information Commissioning Addressing Restart with Defaults Hardware MaintenanceSensor Check Restart Processor cyclingTransducer Block Troubleshooting TroubleshootingSymptom Possible Cause Corrective Action Symptom Possible Causes Corrective ActionAppendix a Reference Data Functional SpecificationsAlarms Update TimeBackup Link Active Scheduler LAS Transient ProtectionPhysical Specifications Function Blocks Performance SpecificationsAccuracy for Differential Configurations Sensor Option Sensor Reference 3-Wire RTDsAccuracy Input RangesAnalog Sensors 4-20mA Sensor Option Alarm Levels AccuracyAmbient Temperature Effect Ambient Temperature Notes Examples Dimensional DrawingsRosemount 848T Top ViewFront View Side View Stainless Steel Junction Box-Cable Gland option code JS2Side View Front View Side View Stainless Steel Junction Box-Conduit Entry option code JS3Aluminum/Plastic Junction Box Styles JA and JP Mounting OptionsStainless Steel Junction Box Style JS Front View Side ViewOptions Ordering InformationSpecial Temperature Test Expanded Software Configuration StandardConduit Electrical Connector Standard Enclosure Options StandardRosemount 848T Appendix B Product Certificates Table B-2. Entity Parameters for Non Incendive Field WiringHazardous Locations Certificates North American ApprovalsPower/Bus Canadian Standards Association CSA Certifications European Approvals Power/Bus SensorAtex Certifications Special Conditions for Safe UseCi = Li = Rosemount 848T IECEx Certifications Special Conditions of Safe UseRosemount 848T China NEPSICertifications Parameters Terminals of power/loopJapanese Certifications Intrinsically Safe and NON-INCENDIVE Installations Installation Drawings Figure B-1. FM Intrinsic Safety/ Fisco 00809-0100-4697, Rev EA Rosemount 848T Figure B-2. CSA Intrinsic Safety/ Fisco Rosemount 848T Rosemount 848T Overview Function Blocks Appendix C Foundation fieldbus TechnologyOutput InputSnap Linkages StatusInstrument- Specific Function Blocks Alerts Device Descriptions Block OperationResource Blocks Transducer BlocksFieldbus Link Network CommunicationLink Active Scheduler LAS MID x ST Data LAS ParametersAddressing Scheduled Transfers Backup LASPublisher/Subscriber Report DistributionDevice Device Y Device Z Unscheduled TransfersSchedule Function Block Scheduling Analog Input AI Function Block Appendix D Function BlocksNumber Parameter Units Description OUTXdscale AlarmhysOutscale IooptsOUT mode in auto OUT mode in manFunctionalitySimulation 63% of ChangeFiltering Signal ConversionDirect IndirectConditions Indirect Square RootValue of the block output OUT may be set manually Table D-3. Alarm Priority LevelsManual Man Advanced Features Uncertain if in Manual modeBAD if Limited Uncertain if LimitedApplication Information AI Block TroubleshootingXdblock HIHILIMIT, LolimitTable D-4. Multiple Analog Input Function Block Parameters Multiple Analog Input MAI Function BlockCAPSTDDEV1 Simulate Figure D-4. Multiple Analog Input Function Block SchematicTable D-5. Blockerr Conditions Option in Manual or Out of Service mode onlyDevices such as flowmeters Block output OUT may be set manually MAI Block Troubleshooting Table D-6. Input Selector Function Block Parameters Input Selector Function BlockIN1 IN2 IN3 IN4 IN5 IN6 IN7 OUT OutrangeMingood SelecttypeSelected OpselectMode Logic Selection INn DISABLEnAlarm OUT FunctionalityOUT reflects the selected value Table D-8. Alarm Priority LevelsUse Uncertain as Good Block ExecutionIsel Block Troubleshooting Numerics IndexMaintalarms Troubleshooting Configuration Errors Modes AutomaticAlarm Detection Errors Modes AutomaticPage Pacific Private Limited Rosemount Inc

848T specifications

The Emerson 848T is a state-of-the-art temperature transmitter designed for accurate and reliable temperature measurement in various industrial applications. This device has gained recognition for its advanced features and robust performance, making it a popular choice among engineers and technicians in the field.

One of the key highlights of the Emerson 848T is its unique dual-channel capability, which allows it to seamlessly monitor two temperature sources simultaneously. This functionality is particularly beneficial in processes where multiple temperature points need to be assessed, optimizing efficiency and reducing the need for additional equipment. It supports various sensor types, including thermocouples, RTDs, and resistance temperature detectors, making it versatile for different applications.

The 848T is equipped with sophisticated digital processing technology, which enhances its accuracy and stability. It features a 24-bit analog-to-digital converter, ensuring precise measurement and minimizing drift over time. Moreover, the device boasts a wide operating temperature range, accommodating ambient conditions from -40°C to 85°C. This durability makes it suitable for harsh environments commonly encountered in industries such as oil and gas, pharmaceuticals, and power generation.

Another significant characteristic of the Emerson 848T is its configurable output options. Users can choose from a range of output signals, including 4-20 mA, which provides a standard interface for integration into existing control systems. Additionally, it offers a HART communication protocol, allowing for easy configuration, calibration, and diagnostics through a digital interface. This feature enhances the transmitter's usability, enabling operators to perform adjustments without direct access to the device.

The device is designed with user-friendliness in mind. Its intuitive setup procedure and robust graphical user interface simplify the commissioning process, ensuring that even those new to the technology can easily navigate the system. An integrated LCD display provides real-time readings and status information, facilitating monitoring at a glance.

In summary, the Emerson 848T temperature transmitter combines reliable performance, user-friendly design, and advanced digital technologies. Its dual-channel capability, wide sensor compatibility, and adjustable output options make it an essential tool for achieving precise temperature measurements in various industrial settings. With these compelling features, the Emerson 848T stands out as a leading choice for professionals seeking accuracy and efficiency in their temperature monitoring applications.
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