GFK-1527A Normal Operation | GE 90-70 specs

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The configured Fail Wait time for the system must be based on the maximum expected or allowable difference in the two CPUs reaching a synchronization point. For example, if one CPU might spend 20ms in the communications phase of the sweep and the other unit might spend 95ms in communications in the same sweep, the Fail Wait time must be set to at least 80ms (80 > 95 -20) to prevent accidental loss of synchronization. Differences in the logic execution window or other phases must also be considered when selecting a Fail Wait time. Some applications limit the possible difference during the communications window by using Constant Sweep mode or Constant Window mode, or by setting the system communications window to LIMITED and selecting a small window time.

GFK-1527A

Chapter 4 Normal Operation

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GE 90-70 manual GFK-1527A Normal Operation

Contents

GE Fanuc Automation GFL-002 Content of This Manual PrefaceRelated Publications Preface Contents Contents Chapter Fault Detection Appendix a Cabling Information Introduction Definition of Terms Enhanced Hot Standby CPU Redundancy Using the Redundancy CPU for Non-Redundant Operation Compatibility with CPU780 Features not Available with Redundancy CPUs Redundancy CPUs as Compared to Other Series 90-70 CPUsDifferences in Operation for Redundancy CPUs Enhanced Redundancy CPU Module Redundancy Communications ModuleRedundant Racks Systems for Enhanced Hot Standby CPU Redundancy Genius I/O Local I/OCable Connections Enhanced Hot Standby CPU Redundancy System with Local I/O Local I/0 Can be Control Strategies GHS Control StrategyGDB Control Strategy Basic Enhanced Hot Standby Operation Output Control with GHSOutput Control with GDB Basic CPU Redundancy Setups Single Bus with Preferred Master GHS Control Strategy Single Bus with Floating Master GDB Control Strategy Critical Data + Redundant Outputs Transferred Dual Bus with Floating Master GDB Control Strategy Paired GBC = INT/EXT Internal External Online Programming On-Line RepairDuplex CPU Redundancy For Installation Instructions System ComponentsSystem Racks Features Redundancy CPU Watchdog Timer CPU ArchitectureExpansion Memory Board CPU Features Memory Protect KeyswitchBattery Connectors CPU LEDs CPU Mode Switch Port Redundancy Communications Module Unit Select Pushbutton Connector RCM Status Leds Connectors Bus Transmitter ModuleBus Transmitter Module Status LEDs Bus Receiver Module Cables and TerminationBus Receiver Module Status LEDs Genius Bus Controller Location of GBCs and Blocks Single Bus Genius Networks Dual Bus Genius Networks Bus Controller LEDs Configuration Requirements Programmer Connection for ConfigurationOne Application Program in Both PLCs Program Folders in Control Programming Software CPU Configuration Parameters Program Folders in Logicmaster Configuring Shared I/O References Parameter Default Range Description Finding the Memory Available for Application Program Storage System Communications Window Considerations Rack Module Configuration Parameters Bus Controller Configuration Parameters Genius I/O Block Configuration Parameters Normal Operation Powerup of a Redundant CPU Incompatible Configurations Resynchronization of a Redundant CPU GHS Control Strategy GDB Control Strategy References for CPU Redundancy Ovrpre %S Reference Not Available Scan Synchronization Sweep Time Synchronization Output Data Transfer to the Backup Unit AT a Data Transfer Time Fail Wait Time GFK-1527A Normal Operation Programming a Data Transfer from Backup Unit to Active Unit Data Transfer Example Disabling 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 Control to the Backup Unit Switching Times RUN 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 RUN Disabled Mode for GDB Control Strategy Example 8 Invalid Finding the Words to Checksum Each Sweep CGR772 CGR935 Finding the Background Window Time Finding the Total Sweep Time Timer and PID Function Blocks Miscellaneous Operation InformationTimed Contacts Multiple I/O Scan Sets Stop to RUN Mode Transition Sequential Function Chart Programming SFCDebugger Background Window Time Genius Bus Controller Switching Ethernet Global Data in a Redundancy CPU Ethernet Global Data Consumption Ethernet Global Data Production Sntp Timestamping Fault Detection Configuration of Fault Actions Fault Detection PLC Fault Table Messages for Redundancy Message Fault Description Corrective Action With redundancy in other fault groups Fault Response Faulting the Redundancy Communications Module Losing a Link Fault Actions in a CPU Redundancy System Configurable Faults Fault Group Type Description Non-Configurable Fault Group Fatal Faults on Both Units in the Same Sweep On-Line Repair Power Supply Maintaining Parallel Bus TerminationOn-Line Repair Recommendations Racks Central Processor Unit Redundancy Communications Module and CablesRedundancy Communications Link Failures Single Bus Networks Bus faults Bus Transmitter ModuleGenius Bus Controller Genius Bus Dual Bus Networks Genius Blocks Specifications Cabling InformationIC690CBL714A Multi-drop Cable Purpose Connector a Connector A, 15-pin Female Battery connectors Bus Controller, Genius Index Index Online programming Online repair Svcreq