Online DCS Migration Tool (Hot Cutover) – Type IST-203

DCS Online Migration Tool (IST 203)

When an old control system needs to be replaced for a new control system during online process conditions, extensive planning and procedures are required. The online migration must be done in the safest and most reliable way to avoid any uncalculated process influences. Istec offers the best solution to perform online control system migrations: The IST-203 Online Migration Tool.

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How does it work?

The Online DCS Migration Tool takes over and simulates 0(4)-20 mA loops during active process conditions. This allows the user to perform an online control system migration without any disturbance of the process, while increasing efficiency and control. It causes no downtime. The Online DCS Migration Tool guides the technician through the online migration process, minimizing human errors and risks. This makes the tool suitable for every online DCS migration strategy.

Application flow

The process starts with connecting the IST-203 to the loop in parallel with the control system. After sampling and storing the loop values, the tool can take-over the loop from the control system. At that point, the tool is in control of the loop, and any changes made to the control system will be absorbed by the tool. The old control system can now be disconnected and replaced by the new control system, while the tool maintains the loop. During the migration, the technician can use the tools offset control function to adjust the loop values if necessary. When the new control system is connected, the tool verifies its output values before it hands over the loop to the new system. Check the application flow for more information.

“The IST-203 Online DCS Migration Tool boosts your migration process”

Key features

  • Improved safety, efficiency and control during DCS or PLC migration
  • Software guided process designed to minimize human errors and risks
  • Offset control – adjusting the loop values during the migration
  • Output match – The IST-203 verifies the new control system output
  • Step-by-step migration
  • Suitable for all control system brands, including Honeywell, Emerson, ABB, Yokogawa, Invensys and others

Case-study: IST-203 used by Yokogawa

Throughout 2016 Istec was involved in a large DCS migration project with the IST-203 Online DCS Migration Tool.

  • Project name: The Great Migration project
  • Companies: Yokogawa, Emerald Kalama Chemical
  • Loops migrated: 4200 I/O’s, 1750 I/O’s with the support of the IST-203 Online DCS Migration Tool
  • Migration start: March 2016

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The IST-203 Online DCS Migration Tool is based on many years of experience in the field of control system migrations and forms the fourth generation in this successful product line. The IST-203 is the most significant version update. While the Hot Cutover (online migration) concept remains the same, the IST-203 comes with a software guided take over process, a connection check and output match, a bigger LCD to display more critical information, increased battery capacity with an emergency backup battery and a lot of other extra features. Click here for the more detailed product presentation or click the image below.



In order to train users and replicate field situations, Istec has designed a training- and test unit. The company also offers training sessions in which users learn more about both the use and the concept of the product. Contact us for more information about training.

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