State Industries GFK-0827 manual Redundancy CPU Considerations

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Redundancy CPU Considerations

The Redundancy CPU (CPU 780) has several restrictions and differences in operation as compared to other Series 90-70 CPUs. The following features are not available with the CPU 780:

HI/O Interrupts

HTimed Interrupts

HVME Integrator Racks.

HStop I/O Scan mode

HFlash operation

Features not Available with CPU 780

I/O Interrupts

I/O Interrupts are not supported by the Redundancy CPU (CPU 780). This includes the single edge triggered interrupts from the discrete input modules, the high alarm and low alarm interrupts from the analog input modules, and interrupts from foreign VME modules, all of which can be used to trigger a ladder diagram program block. In order to prevent I/O interrupts from changing the data being transferred from one CPU to another, interrupts would have to be disabled for the entire transfer time. Programs which declare I/O Interrupt triggers cannot be stored to the CPU 780 (the program will be rejected causing an abort of the store). In addition, any configuration containing an enabled I/O interrupt for a discrete or analog input module will cause a fatal system configuration mismatch fault.

Timed Interrupts

Timed Interrupts are not supported by the Redundancy CPU (CPU 780). Timed Interrupts would have the same interrupt latency problem as the I/O Interrupts. Programs which declare Timed Interrupt triggers cannot be stored.

VME Integrator Racks

The VME Integrator Racks (IC697CHS782 and IC697CHS783) that support half size modules are not supported with this release of the Hot Standby CPU Redundancy product.

STOP/IOSCAN Mode

TheSTOP/IOSCAN mode is not valid in a redundant system. If an attempt is made to place the PLC in this mode, the PLC will reject the selection and return an error. A message will be displayed on the programmer with this information.

Flash Operation

Flash memory operation is not supported in this release of the CPU 780.

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Series 90-70 Hot Standby CPU Redundancy User's Guide ± December 1993

GFK-0827

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Contents GE Fanuc Automation GFL±002 Related Publications Content of this ManualWe Welcome Your Comments and Suggestions PrefaceContents Chapter System Components Chapter Configuration Chapter Operation System Operation Fault Detection and Control Actions Synchronized Hot Standby CPU Redundancy System Configuration Contents Hot Standby CPU Redundancy Product Chapter IntroductionGFK-0827 Benefits of the Hot Standby CPU Redundancy Product Features of the Hot Standby CPU Redundancy ProductCable Connections Systems for Hot Standby CPU Redundancy SystemsGenius I/O System Local I/O SystemControl Strategy Basic Hot Standby OperationSynchronized Hot Standby CPU Redundancy System Configuration Redundancy Communications Module Redundancy CPU ModuleEffect on Scan Time Bumpless SwitchingSwitch to Backup Unit Time Synchronized CPUsConfigurable Backup Data Size On-Line ProgrammingOn-Line Repair Programming Considerations Configuration RequirementsTerm Definition Definition of TermsAcronym Definition Commonly Used AcronymsRedundancy CPU Chapter System ComponentsWatchdog Timer CPU ArchitectureCapacities for Redundancy CPU, IC697CPU780 Redundancy CPU IC697CPU CPU FeaturesValid Operating Mode Selection CPU Mode SwitchMemor y Protect Keyswitch Battery ConnectorsCPU Status LEDs Serial Port Connector Expansion Memory BoardExpansion Memory Boards for CPU Redundancy Communications Module RCM FeaturesBoard OK RCM System Status LedsUnit Selection Pushbutton RCM ConnectorsBus Transmitter Module LED Status IndicatorsBus Receiver Module BTM ConnectorsBus Signal Termination BRM ConnectorsGenius Bus Controller Genius Bus Controller User Features Racks GBC ConnectorsConfiguring a Hot Standby CPU Redundancy System Chapter ConfigurationRedundancy System Requirements Basic Redundancy System SetupLogicmaster 90 Configuration System ConfigurationMonitor or Online mode Screens for Fault Category ConfigurationHandling Folders Configuration with LogicmasterConfiguration of a Redundancy CPU Module GFK-0827 Redundant CPU Requirements Normal Sweep Mode Redund TypeBackground Window Constant Sweep Mode Constant Window Sweep ModeCtrl Strgy Fail WaitShared I/O Shared I/O Reference Values Shared I/O Data ParametersReference Type ReferenceSize CalculationforNumberofBytes Transfer Data SizeConfiguring a CPU Expansion Memory Board Configuration of a Redundancy Communications Module Configuration Paired GBC Parameter Configuration of a Genius Bus ControllerSerial Bus Address Configuring a Primary Redundant PLC Select the Redundancy CPU Module Select an Expansion Memory Board Configure the Redundant Communications Module Configure a Genius Bus Controller Configuration Configure Genius I/O Blocks Configure the Bus Transmitter Module Configuring a Secondary Redundant PLC Change Redund Type GFK-0827 Chapter Operation Power-Up Sequence of a Redundant CPUIncompatible Configurations Resynchronization of the Redundant CPU Hot-Standby Redundancy Control Strategy First Data Transfer %I, %AI and Synchronization Synchronous ScanData Transfer from Backup Unit to Active Unit Second Data Transfer %Q, %AQ, %R, and %M Switching Control to Backup UnitRole Switch Svcreq Definition for% S Reference for Redundancy Status References for CPU RedundancyRedundancy CPU Considerations Differences in Operation for CPU RUN Disabled ModeRUN/ENABLED Locrdy Locact Remrdy Remact Configuration of Fault Actions Background Window Time Stop to RUN Mode TransitionWords per Sweep = Ovrpre %S Reference Timed ContactsGenius Bus Controller Switching Fault Categories Fault DetectionChanging Fault Category Actions Fault Zoom Help Text for Redundancy Error Codes PLC Fault TableFaulting RCMs, Losing Links, and Terminating Communications GFK-0827 Maskable Fault Group Descriptions Fault Actions in a CPU Redundancy SystemUserConfigurable Maskable Fault Group ActionsNon-Maskable Fault Action Descriptions Non-Maskable Fault Group DescriptionsOn-Line Repair Maintaining Parallel Bus TerminationOn-Line Repair Recommendations Redundancy Communications Module and Cables Power SupplyRacks Central Processor UnitRedundancy Communications Link Failures Bus Transmitter ModuleGenius Bus Controller GeniusBlocks Genius BusRedundancy Alternatives Appendix Redundancy AlternativesRedundancy Option Key See Table PLC RedundancyOptionsSeries 90-70 Redundancy Through Application Logic Index Index Index Index Index