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Hot Cutover Tool for Control systems Hardware

Parijat Controlware Inc > Hot Cutover Tool for Control systems Hardware


Overview: Many control systems are getting old without improvements or approaching end of their life. These plants should start migration to a new control system before issues start to occur.

Two common approaches for a migration:

  • Offline (cold) cutover; complete replacementat once
  • Online (hot) cutover; migration without plantshutdown

A hot cutover is an approach of replacing the old control system while the plant is operational. The old and the new control systems operate simultaneously, and the new system is cutover point by point, loop by loop.

Hot Cutover requires intense Planning with plant operations to Install, Commission and Integrate New Control Systems with the Existing Systems without taking sections of the running Plant into Shutdown mode. PCI will not be responsible for any kind of impact. The implementors and all stake holders use this on their own responsibility. Ensure the tool’s suitability for your application to your satisfaction and full understanding before using it.

PCI Hot Cutover Tool: Allows user to safely migrate to a newer control system without having any or minimal downtime. For some I/O’s an online migration can be an issue because of their critical nature to the process. Disconnecting these critical control loops can result in shutdown which could be critical to the process conditions. In these situations, PCI Hot Cutover Tool proves its value; it can take-over even some of the critical loops, while maintaining optimal control of the process.

Various Possibilities

A. I/OPanels

  • Use existing
  • Use New Panels

B.Old Controllers I/O update w r t logic scan

  • Synchronous
  • Asynchronous

C. System options

  • Same vendor’s products
  • Different vendor’s products
  • Use some custom configurations in new system


  • Old controller logic is editable and editors are available
  • New controller(s) programs fully tested/debugged in lab
  • Both controllers can survive rack faults
  • Once the process starts, it is hard to reverse. Unless undo everything in reverse.
  • A high speed PC with MS Windows and ready to communicate with both systems is required. PCI will provide the software. Both controllers allow high speed and voluminous data transfers.
  • Must evaluate all possibilities and keep backup plans in place and ready.


  • Marshalling panels Terminal strips not required. Use the terminals of I/O modules themselves.
  • Relatively Easy operation
  • Safe and controlled hot cut-over
  • Maximum efficiency
  • Minimization of human errors and risks
  • Preventing production downtime
  • Generally independent of the type of existing or new control system HW.

Process sequence explanation

The process starts with an initial study/report of inventory of all processes and related instruments that will be affected by the migration. Define the critical loops and perform the necessary hazard and operability studies. Identify new control hardware (PLC, I/Os, Switches, Power supply, etc.) to match existing control system. Identify any new additions or changes required.

Best to have PCI work as a partner in these sessions.

Connected parallel to existing control system and verify connection to control loops and ready to read & write with both controllers using PCI.