On-Line Repair | GE 90-70 guide

5

On-Line Repair

With a Hot Standby CPU Redundancy system, most system component failures can be repaired by replacing the failed component while the system is online. These online repair procedures are possible because of the role-switching capability of the units in the system. Status of the Primary and Secondary Units is determined by observing the LEDs on the Redundancy Communications Module.

There are two basic situations regarding the active and backup units that you should be aware of when a component needs to be replaced.

1.If the failure is in the active system, control switches to the backup system. Power can then be removed from the rack containing the failed component. When the component is replaced, power is restored to the rack, and the CPU is returned to RUN mode, the CPU becomes synchronized with the current active unit.

2.If the failure is in the backup system, remove power from the rack containing the failed component and replace the component. When power is restored to the backup unit and the CPU is returned to RUN mode, it becomes synchronized with the active unit.

The following paragraphs describe how the system can be repaired without interruption of control. The replacement of each replaceable component is described.

Note

If maintenance is to be performed on the active unit in a synchronized system, control should be switched to the other unit before powering down. This will allow for an orderly transfer of control.

After repairing a defective unit:

1.Power-up the CPU rack in STOP mode.

2.Verify that the Remote Ready and Remote Active LEDS are on while in STOP mode.

3.Verify that the Local Ready and Local Active LEDs are on in the Active unit.

4.Clear the fault tables of the repaired unit.

5.Put the repaired unit in RUN mode.

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

GFK-1527A

Image 74

GE 90-70 manual On-Line Repair

Contents

GE Fanuc Automation GFL-002 Related Publications Content of This ManualPreface 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 Differences in Operation for Redundancy CPUs Features not Available with Redundancy CPUsRedundancy CPUs as Compared to Other Series 90-70 CPUs Redundant Racks Enhanced Redundancy CPU ModuleRedundancy Communications Module Systems for Enhanced Hot Standby CPU Redundancy Cable Connections Genius I/OLocal I/O Enhanced Hot Standby CPU Redundancy System with Local I/O Local I/0 Can be GDB Control Strategy Control StrategiesGHS Control Strategy Output Control with GDB Basic Enhanced Hot Standby OperationOutput Control with GHS 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 Duplex CPU Redundancy Online ProgrammingOn-Line Repair System Racks For Installation InstructionsSystem Components Features Redundancy CPU Expansion Memory Board Watchdog TimerCPU Architecture Battery Connectors CPU FeaturesMemory Protect Keyswitch CPU LEDs CPU Mode Switch Port Redundancy Communications Module Unit Select Pushbutton Connector RCM Status Leds Bus Transmitter Module Status LEDs ConnectorsBus Transmitter Module Bus Receiver Module Status LEDs Bus Receiver ModuleCables and Termination Genius Bus Controller Location of GBCs and Blocks Single Bus Genius Networks Dual Bus Genius Networks Bus Controller LEDs One Application Program in Both PLCs Configuration RequirementsProgrammer Connection for Configuration 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 Validating the Backup PLCs Logic Solution Backup Qualification with Svcreq #43Validating the Backup PLCs Input Scan Switching Control to the Backup Unit Switching Times Example 1 Role switches allowed on both units RUN Disabled ModeRUN Disabled Mode for GHS Control Strategy Example 4 Role switches allowed on both units Example 2 Role switches allowed on both unitsExample 3 Role switches not allowed on either unit 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 Timed Contacts Timer and PID Function BlocksMiscellaneous Operation Information Multiple I/O Scan Sets Debugger Stop to RUN Mode TransitionSequential Function Chart Programming SFC 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 On-Line Repair Recommendations Power SupplyMaintaining Parallel Bus Termination Racks Redundancy Communications Link Failures Central Processor UnitRedundancy Communications Module and Cables Genius Bus Controller Single Bus Networks Bus faultsBus Transmitter Module Genius Bus Dual Bus Networks Genius Blocks IC690CBL714A Multi-drop Cable SpecificationsCabling Information Purpose Connector a Connector A, 15-pin Female Battery connectors Bus Controller, Genius Index Index Online programming Online repair Svcreq