Emerson manual Rosemount 848L, Reference Manual, 00809-0100-4696,Rev AA September

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Rosemount 848L

Reference Manual

00809-0100-4696, Rev AA September 2004

Logic Operator Functions

The following combinatorial operators require a minimum of 2 and a maximum of 10 functions between the parentheses, each separated by a comma.

AND ( ) - Performs the logical ‘and’ of the argument functions.

OR ( ) - Performs the logical ‘or’ of the argument functions.

XOR ( ) - Performs the logical exclusive ‘or’ of the argument functions. An XOR function is false if all of the arguments are the same value, either all true or all false. Otherwise it is true.

The following unary operator requires just one argument:

NOT ( ) - Performs the logical inversion of the argument function.

Limits on Functions

There is no limit to the number of functions described above, as long as they fit within the 20 equations described by 80 character strings. The following functions are limited to 10 of each within the entire set of 20 equations. This is because the functions require memory to store constants or last values. The size of a memory element is 16 bits, so the maximum size of a constant value is 65535. There are no signed numbers.

Edge Detection Functions

RISE ( ) - This function evaluates as false unless the previous value of the argument was false and now the argument evaluates to true. This function is true for only one equation evaluation cycle. It will always be false on the following cycle.

FALL( ) - This function evaluates as false unless the previous value of the argument was true and now the argument evaluates to false. This function is true for only one equation evaluation cycle. It will always be false on the following cycle.

Clock Function

NOTE

All arguments of time are in tenths of a second.

CLOCK (onTime,offTime) - The parameters onTime and offTime are constants. This function does not take other functions. CLOCK runs unconditionally with a period determined by onTime plus offTime. Time is specified in tenths of a second. The function will be true for onTime tenths of a second. On the first evaluation cycle after the device starts up, the onTime interval will start because all of the dynamic values are zero. Use the NOT function to invert this behavior, and swap the on and off times.

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Contents Reference Manual 00809-0100-4696,Rev AA SeptemberRosemount 848L Discrete Logic Temperature Transmitter withRosemount 848L FOUNDATION FieldbusTable of Contents SECTION 1 Introduction SECTION 2 InstallationSECTION 3 Configuration Rosemount 848LSECTION Operation and Maintenance APPENDIX A Reference Data APPENDIX B Product CertificationsAPPENDIX C Function Blocks Rosemount 848LAPPENDIX D Logic Equation Syntax APPENDIX E Motor ControlAPPENDIX F Valve Control Rosemount 848LRosemount 848L Reference ManualTOC-4 SAFETY MESSAGES Warnings SectionIntroduction Rosemount 848LOVERVIEW TransmitterManual Rosemount 848LRosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference ManualInstallation SAFETY MESSAGES Warnings MOUNTINGSection Rosemount 848LMounting to a DIN Rail Without an Enclosure Mounting to a Panel with a Junction BoxRosemount 848L Reference ManualMounting to a 2-InchPipe Stand Rosemount 848LReference Manual 00809-0100-4696,Rev AA SeptemberWIRING Power Supply ConnectionsRosemount 848L Reference ManualSWITCHES Surges/TransientsGROUNDING Rosemount 848LRosemount 848L Reference Manual00809-0100-4696,Rev AA September I/O WIRING DISCRETE INPUT WIRING CONFIGURATIONDISCRETE OUTPUT WIRING CONFIGURATION Rosemount 848LTAGGING Rosemount 848LReference Manual INSTALLATION Using Cable Glands TRANSMITTER LABELRosemount 848L Reference ManualUsing Conduit Entries Rosemount 848LReference Manual Configuration OVERVIEW SAFETY MESSAGES WarningsSection Rosemount 848LGENERAL BLOCK INFORMATION Modes Rosemount 848LReference Manual Link Active Scheduler Block Instantiation Rosemount 848LReference Manual RESOURCE BLOCK FEATURES and FEATURES SEL CapabilitiesRosemount 848L Reference ManualMAX NOTIFY Rosemount 848LReference Manual PlantWeb Alarms Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Alarms I/O TRANSDUCER BLOCK Rosemount 848LReference Manual LOGIC TRANSDUCER BLOCK Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Figure 3-1.848L Logic Transmitter Data FlowRosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September DISCRETE INPUT BLOCKS Rosemount 848LReference Manual DISCRETE OUTPUT BLOCKS MULTIPLE DISCRETE INPUT BLOCKMULTIPLE DISCRETE OUTPUT BLOCK Rosemount 848LRosemount 848L Reference ManualSection 4 Operation and Maintenance FOUNDATION FIELDBUS INFORMATIONSAFETY MESSAGES Warnings Rosemount 848LMAINTENANCE Communication/PowerResetting the Configuration RESTART CommissioningTROUBLESHOOTING I/O Transducer and Logic Block TroubleshootingResource Block NAMUR SensorsRosemount 848L Reference ManualSPECIFICATIONS Functional Specifications Appendix AReference Data Rosemount 848LRosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Physical Specifications Function Blocks SpecificationRosemount 848L Reference ManualDIMENSIONAL DRAWINGS Rosemount 848LReference Manual Figure A-3.Rosemount 848L Wiring Diagram Rosemount 848LReference Manual 00809-0100-4696,Rev AA SeptemberORDERING INFORMATION Rosemount 848LReference Manual Rosemount 848L Reference ManualAppendix B Product Certifications APPROVED MANUFACTURING LOCATIONSEUROPEAN DIRECTIVE INFORMATION HAZARDOUS LOCATIONS CERTIFICATES North American ApprovalsEuropean Approvals Rosemount 848LReference Manual Appendix C Function Blocks RESOURCE BLOCK PARAMETERSRosemount 848L Reference ManualRosemount 848L Reference ManualFREE SPACE Rosemount 848L Reference ManualOUTPUT ADVISE ENABLE Rosemount 848LReference Manual I/O TRANSDUCER PARAMETERS Rosemount 848LReference Manual 00809-0100-4696,Rev AA SeptemberRosemount 848L Reference ManualTRANSDUCER TYPE Rosemount 848L Reference ManualOUT 3 TAG LOGIC TRANSDUCER PARAMETERS Rosemount 848LReference Manual 00809-0100-4696,Rev AA SeptemberDISCRETE INPUT BLOCK Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Table C-4.ParametersDISCRETE OUTPUT BLOCK Supported Modes Rosemount 848LReference Manual MULTIPLE DISCRETE INPUT BLOCKS Rosemount 848LReference Manual Rosemount 848L Reference ManualMULTIPLE DISCRETE OUTPUT BLOCK 00809-0100-4696,Rev AA SeptemberRosemount 848L Reference Manual00809-0100-4696,Rev AA September Table C-7.Parameters andAppendix D Logic Equation Syntax Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Table D-1.Supported FunctionsRosemount 848L Reference ManualPS channel number, divisor ERROR HANDLING Table D-2.Error HandlingRosemount 848L Reference ManualEXAMPLES Rosemount 848LReference Manual Rosemount 848L Reference ManualAppendix E Motor ControlINTRODUCTION TO MOTOR CONTROL Rosemount 848LVARIATIONS ON MOTOR CONTROL Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September WRITING 848L EQUATIONS Basic Motor Control Rosemount 848LReference Manual Interlock Permissive Emergency Shutdown Rosemount 848LReference Manual Restart Delay Rosemount 848LReference Manual Maximum Restarts Rosemount 848LReference Manual Winding Temperature Rosemount 848LReference Manual Hand-Off-Auto Rosemount 848LReference Manual Intermediate Stop Rosemount 848LReference Manual Redundant Motors - Alternate Start Rosemount 848LReference Manual Redundant Motors - Timed Switch Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Redundant Motors - Switch on Failure Rosemount 848LReference Manual Rosemount 848L Reference Manual00809-0100-4696,Rev AA September Rosemount 848L Reference ManualE-16 Appendix F Valve ControlINTRODUCTION TO VALVE CONTROL Rosemount 848LAlarms Variations on Valve Control Rosemount 848LReference Manual Boolean Expressions Basic Valve Control Rosemount 848LReference Manual Open-Auto-Close Alarm Variations Output Variations Output with InterlockRosemount 848L Reference ManualSimple Valve Variations Permissive Rosemount 848LReference Manual Double Block and Bleed Rosemount 848LReference Manual Motorized Valve Heat Exchange Medium Selection Rosemount 848LReference Manual Rosemount 848L Reference ManualIndex Rosemount 848LReference Manual 00809-0100-4696,Rev AA 9/17/04Rosemount 848L Reference Manual00809-0100-4696,Rev AA 9/17/04 Rosemount 848L Reference Manual00809-0100-4696,Rev AA 9/17/04 Rosemount 848L Reference ManualIndex-4 ¢00809-0100-4697F¤ Reference Manual