TN - What is and how to set the USER ID Password on the NX/NJ Controllers

Summary/Issue Description

The Authentication of the User Program Execution ID is a security feature designed to prevent unauthorized users from using the user program in a different controller. By entering a specific ID for the Controller, only the user program assigned that ID can be executed on that Controller.

It is important to note that this function differs from other protection mechanisms, as the user program can still be edited and viewed.

Root Cause

Users attempt to change the programming or create a backup of the PLC to download it to another one. Using this Authentication ID doesn't allow users to copy the programs to be used in other controllers.

After you assign a user program execution ID to the CPU Unit, you cannot read or delete the ID. To delete the ID from the CPU Unit, perform the Clear All Memory operation on the CPU Unit.

Solution

Follow these precautions:

• A user program execution ID can be set only once for a user program.
• Record the user program execution ID to ensure you do not lose it.
• We recommend that you backup the project file before you set the user program execution ID. 

Follow the steps below to set the program execution ID security: 

1 - While offline, go to the Controller menu, then security, then select ID for User Program Execution: 

2 - Enter the User Program Execution ID and enter the same ID in the User Program Execution ID (Confirmation) field, and then click the OK Button:

Note: After you assign a user program execution ID to a user program, you cannot change or delete the ID. 

3 - To enable the User Program Execution IDs Verification on the PLC, go online with the controller and change it to program mode, open the Controller menu, and then select Mode and Program: 

4 - Click on the Controller Menu, then Transfer and select Transfer to. Set the same ID that you set in the program and transfer it to the controller:

Note: Be sure to record the user program execution ID to ensure you do not lose it. You cannot change the user program execution ID even if you lose it.

5 - Cycle power the controller to enable the new security ID.

Date/Revision History

First review 09/22/2025 V1.0

Author:

Karla Flores Avila, Technical Support Specialist

References

Sysmac Studio Version 1 Operation Manual 

NJ/NX-series CPU Unit Software User's Manual