Emerson 848T Device Descriptions Block Operation, Instrument- Specific Function Blocks Alerts

Page 85

Reference Manual

00809-0100-4697, Rev EA October 2011

Rosemount 848T

DEVICE DESCRIPTIONS

BLOCK OPERATION

Instrument- Specific Function Blocks

Alerts

Device Descriptions (DD) are specified tool definitions that are associated with the Resource and Transducer Blocks. Device descriptions provide the definition and description of the function blocks and their parameters.

To promote consistency of definition and understanding, descriptive information, such as data type and length, is maintained in the device description. Device Descriptions are written using an open language called the Device Description Language (DDL). Parameter transfers between function blocks can be easily verified because all parameters are described using the same language. Once written, the device description can be stored on an external medium, such as a CD-ROM or diskette. Users can then read the device description from the external medium. The use of an open language in the device description permits interoperability of function blocks within devices from various vendors. Additionally, human interface devices, such as operator consoles and computers, do not have to be programmed specifically for each type of device on the bus. Instead their displays and interactions with devices are driven from the device descriptions.

Device descriptions may also include a set of processing routines called methods. Methods provide a procedure for accessing and manipulating parameters within a device.

In addition to function blocks, fieldbus devices contain two other block types to support the function blocks. These are the resource block and the transducer block.

Resource Blocks

Resource blocks contain the hardware–specific characteristics associated with a device; they have no input or output parameters. The algorithm within a resource block monitors and controls the general operation of the physical device hardware. The execution of this algorithm is dependent on the characteristics of the physical device, as defined by the manufacturer. As a result, the algorithm may cause the generation of events. There is only one resource block defined for a device. For example, when the mode of a resource block is “Out of Service (OOS),” it impacts all of the other blocks.

Transducer Blocks

Transducer blocks connect function blocks to local input/output functions. They read sensor hardware and write to effector (actuator) hardware. This permits the transducer block to execute as frequently as necessary to obtain good data from sensors and ensure proper writes to the actuator without burdening the function blocks that use the data. The transducer block also isolates the function block from the vendor–specific characteristics of the physical I/O.

When an alert occurs, execution control sends an event notification and waits a specified period of time for an acknowledgment to be received. This occurs even if the condition that caused the alert no longer exists. If the acknowledgment is not received within the pre-specified time-out period, the event notification is retransmitted, assuring that alert messages are not lost.

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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 terminalsThermocouple or Millivolt Inputs RTD or Ohm InputsAnalog Inputs Power Supply ConnectorsOhm resistor in the loop when switched to the left Analog InputSurges/Transients Power SupplyConnections 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 Cable Glands InstallationUsing Conduit Entries Section Configuration Transmitter Configuration Custom Configuration Methods ConfigurationStandard 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 Resource Block Block ConfigurationNumber Parameter Description 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 AlarmsAdvisory Alarms Maintenance Alarms/Priority AlarmAlarm Recommended Actions for PlantWeb Alerts Alarm Type Active Event Recommended ActionRESOURCE.HARDWAREREV, Transducer BlocksRESOURCE.RBSFTWRREVALL 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 12. Sensorconfig Sub-Parameter Structure 11. Xderror Sub-Parameter StructureTransducer Block Sub-Parameter Tables 14. Sensorcal Sub-Parameter Structure 13. Sensorstatus Sub-Parameter Structure15. Calstatus Structure 16. Transducer Status Sub-Parameter StructureDual Sensor Status Table StructureStructure Sensor Calibration in the Sensor Transducer Block 20. Validation Config Sub-Parameter StructureStructure Parameter Description Rosemount 848T Foundation Fieldbus Information Operation and MaintenanceFoundation 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 ViewSide View Front View Stainless Steel Junction Box-Cable Gland option code JS2Front View Side 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 BlocksLink Active Scheduler LAS Network CommunicationFieldbus Link MID x ST Data LAS ParametersAddressing Scheduled Transfers Backup LASPublisher/Subscriber Report DistributionSchedule Unscheduled TransfersDevice Device Y Device Z 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 RootManual Man Table D-3. Alarm Priority LevelsValue of the block output OUT may be set manually 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 SchematicDevices such as flowmeters Option in Manual or Out of Service mode onlyTable D-5. Blockerr Conditions 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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