GE 90-70 manual Ethernet Global Data in a Redundancy CPU, Ethernet Global Data Consumption

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Ethernet Global Data in a Redundancy CPU

Ethernet Global Data is enhanced to provide optimal use with Redundancy CPUs. Configuration of Ethernet Global Data requires the use of Control Programming software, release 2.1 or later.

Ethernet Global Data Consumption

Either or both of the PLC units in a synchronized system can consume Ethernet Global Data. Consumption by individual units requires separate Ethernet Global Data configurations for the two units and therefore separate folders. If an exchange should be consumed by both units in a redundant system, the exchange must be multicast and the exchange must be configured to be consumed in each of the two units.

A single folder may be used for Ethernet Global Data configuration if there are no exchanges consumed or produced only by one of the two units.

Consumption of configured Ethernet Global Data exchanges occurs in RUN mode regardless of the Active/Backup state of the CPU and regardless of whether or not the units are synchronized.

The consumption of the Ethernet Global Data exchanges occurs independently on the two CPUs even when the same exchange is consumed in both units. The Ethernet modules obtain a copy of multicast exchanges at the same time, but polling of the exchange in the two CPUs may be phased by one or more sweeps. This can result in the two units seeing different values for the same exchange in a given sweep.

For example, an exchange might be consumed by the CPUs at a rate of 500ms. If the CPUs had a sweep time of 100ms, the same exchange might be seen 400ms later in one CPU than in the other. It may or may not be from the same exchange produced by the host.

Example

The diagram below shows an example with a sweep time of 100ms and an exchange that is produced every 300ms and consumed every 500ms.

Exchange Production from Host

X

X

X

X

CPU Sweeps

 

 

 

 

 

Consumption by CPU A

X

 

X

 

X

Consumption by CPU B

 

 

X

 

X

If data from the exchanges must be seen identically on the two units, the reference data for the exchanges can be transferred from the active unit to the backup unit during the input data transfer. That transfer occurs shortly after the Ethernet Global Data consumption portion of the CPU sweep. Exchange variables transferred must be placed into %I or %AI memory to participate in the input data transfer.

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Series 90™-70 Enhanced Hot Standby CPU Redundancy User's Guide – May 2000

GFK-1527A

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Contents GE Fanuc Automation GFL-002 Content of This Manual PrefaceRelated Publications Preface Contents Contents Chapter Fault Detection Appendix a Cabling Information Definition of Terms IntroductionEnhanced Hot Standby CPU Redundancy Compatibility with CPU780 Using the Redundancy CPU for Non-Redundant OperationFeatures not Available with Redundancy CPUs Redundancy CPUs as Compared to Other Series 90-70 CPUsDifferences in Operation for Redundancy CPUs Systems for Enhanced Hot Standby CPU Redundancy Enhanced Redundancy CPU ModuleRedundancy Communications Module Redundant RacksGenius I/O Local I/OCable Connections Local I/0 Can be Enhanced Hot Standby CPU Redundancy System with Local I/OControl Strategies GHS Control StrategyGDB Control Strategy Basic Enhanced Hot Standby Operation Output Control with GHSOutput Control with GDB Single Bus with Preferred Master GHS Control Strategy Basic CPU Redundancy SetupsCritical Data + Redundant Outputs Transferred Single Bus with Floating Master GDB Control StrategyPaired GBC = INT/EXT Internal External Dual Bus with Floating Master GDB Control StrategyOnline Programming On-Line RepairDuplex CPU Redundancy For Installation Instructions System ComponentsSystem Racks Redundancy CPU FeaturesWatchdog Timer CPU ArchitectureExpansion Memory Board CPU LEDs CPU FeaturesMemory Protect Keyswitch Battery ConnectorsPort CPU Mode SwitchUnit Select Pushbutton Redundancy Communications ModuleRCM Status Leds ConnectorConnectors Bus Transmitter ModuleBus Transmitter Module Status LEDs Bus Receiver Module Cables and TerminationBus Receiver Module Status LEDs Location of GBCs and Blocks Genius Bus ControllerDual Bus Genius Networks Single Bus Genius NetworksBus Controller LEDs Program Folders in Control Programming Software Configuration RequirementsProgrammer Connection for Configuration One Application Program in Both PLCsProgram Folders in Logicmaster CPU Configuration ParametersParameter Default Range Description Configuring Shared I/O ReferencesSystem Communications Window Considerations Finding the Memory Available for Application Program StorageBus Controller Configuration Parameters Rack Module Configuration ParametersGenius I/O Block Configuration Parameters Normal Operation Powerup of a Redundant CPU Resynchronization of a Redundant CPU Incompatible ConfigurationsGDB Control Strategy GHS Control StrategyOvrpre %S Reference Not Available References for CPU RedundancySweep Time Synchronization Scan SynchronizationAT a Output Data Transfer to the Backup UnitFail Wait Time Data Transfer TimeGFK-1527A Normal Operation Data Transfer Example Programming a Data Transfer from Backup Unit to Active UnitDisabling Data Transfer Copy in Backup Unit Svcreq #43 Command Block for Svcreq #43 Backup Qualification with Svcreq #43 Validating the Backup PLCs Input ScanValidating the Backup PLCs Logic Solution Switching Times Switching Control to the Backup UnitRUN Disabled Mode RUN Disabled Mode for GHS Control StrategyExample 1 Role switches allowed on both units Example 2 Role switches allowed on both units Example 3 Role switches not allowed on either unitExample 4 Role switches allowed on both units Backup Active Example 8 Invalid RUN Disabled Mode for GDB Control StrategyCGR772 CGR935 Finding the Words to Checksum Each SweepFinding the Total Sweep Time Finding the Background Window Time Multiple I/O Scan Sets Timer and PID Function Blocks Miscellaneous Operation Information Timed ContactsBackground Window Time Stop to RUN Mode TransitionSequential Function Chart Programming SFC DebuggerGenius Bus Controller Switching Ethernet Global Data Consumption Ethernet Global Data in a Redundancy CPUSntp Timestamping Ethernet Global Data ProductionConfiguration of Fault Actions Fault DetectionFault Detection Message Fault Description Corrective Action PLC Fault Table Messages for RedundancyWith redundancy in other fault groups Fault Response Losing a Link Faulting the Redundancy Communications ModuleFault Actions in a CPU Redundancy System Fault Group Type Description Configurable FaultsFatal Faults on Both Units in the Same Sweep Non-Configurable Fault GroupOn-Line Repair Racks Power SupplyMaintaining Parallel Bus Termination On-Line Repair RecommendationsCentral Processor Unit Redundancy Communications Module and CablesRedundancy Communications Link Failures Genius Bus Single Bus Networks Bus faultsBus Transmitter Module Genius Bus ControllerGenius Blocks Dual Bus NetworksPurpose SpecificationsCabling Information IC690CBL714A Multi-drop CableConnector a Connector A, 15-pin Female Index Battery connectors Bus Controller, GeniusIndex Online programming Online repair Svcreq
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