Tracking Transfer - Mitsubishi Electric MELSEC iQ-R-R00CPU User Manual

37.2

Tracking Transfer

This function transfers the control data from the control system to the standby system and maintains the consistency of the
data in the two systems to continue operation of the redundant system when a failure or an error occurs in the control system.
Control system
• The control system CPU module sends tracking data to the standby system CPU module before the END processing. The
tracking data includes special relay (SM), special register (SD), PID control instruction information, and system data in
addition to device (standard/safety device)/label (standard label, safety label, and standard/safety shared label) data. (
Page 623 Tracking data)
• The standby system CPU module receives the tracing data, and then reflects the received data on the device/label
memory.
• Standard device/standard label data can be divided and transferred as required. To transfer device/label data within a
desired range, set a range of standard global devices to be transferred or whether to transfer standard local devices/
standard global labels/standard local labels for each tracking block and turn on the tracking triggers (SD1667 to SD1670)
assigned for each tracking block.
• Up to 1M-word standard device/standard label data can be transferred in one scan.
• During an online change or when a stop error has occurred, tracking transfer is performed only for system data. ( Page
625 System data)
• In the CPU parameters, "Tracking Device/Label Setting" under "Tracking Setting" in "Redundant System
Settings" is set to "Transfer collectively" by default. Thus, tracking transfer is performed without setting the
parameter. ( Page 629 Batch transfer)
• When "Process Control Extension Setting" is enabled, the tracking transfer setting is automatically
configured in detailed settings. The range of the file register specified to the system resource of the optional
process control extension setting is registered to the tracking block No.64. ( Page 628 When "Process
Control Extension Setting" is enabled)
When a tracking transfer is not performed, the possible causes are the following:
• The standby system CPU module has been powered off or reset.
• Hardware failure of the CPU module has occurred.
• An error has occurred in the redundant function module.
• A WDT error has occurred.
• Tracking cables has been pulled out or disconnected.
*1 When the tracking communication line properly works, "Link-up" (event code: 00100) may be stored in the event history.
37 FUNCTIONS
622
37.2 Tracking Transfer
Standby system
Sending tracking data
*1
*1
*1