How can we help you today?

Connection lost between the Unity-Pro PC and the PLC just after the Run command through the USB driver

Symptoms

The Unity-Pro project is transferred through the USB port and the connection is lost just after the Run command.
The animation remains frozen and the following message is displayed :
"PLC failed - Automatic return to off line"

The PLC remains in Run mode, every time you try to connect it again the same message is displayed.

How to fix

The connection is lost because the project has a long Scan Time and the request takes more time than the driver timeout to get an answer.

You have to change the timeout of the driver, for that :
- Under Unity-Pro, select in the menu PLC -> Set Address,

Setting PLC Address

- In the PLC area, click on the "Communication Parameters" button,

PLC Communication Timeout Parameter
You can increase the Timeout to 10 seconds in order to stay connected.

-Click OK to validate.

Schneider Electric Canada

Explore more
Category:
Users group

Discuss this topic with experts

Visit our community and get advice from experts and peers on this topic and more
Explore more
Category:

Need help?

Need help?

Product Selector

Product Selector

Quickly and easily find the right products and accessories for your applications.

Get a Quote

Get a Quote

Start your sales inquiry online and en expert will connect with you.

Where to buy?

Where to buy?

Easily find the nearest Schneider Electric distributor in your location.

Help Center

Help Center

Find support resources for all your needs, in one place.

  • Help and Contact Center
  • Contact Sales
  • Find our Offices
  • Where to Buy
  • Careers
  • Company Profile
  • Investors
  • Newsroom
  • Report a Misconduct
  • Product Documentation
  • Product Selectors
  • Software and Firmware
  • Product Substitution and Replacement
  • Blog
  • Events
  • Schneider Electric Community
  • Sustainability
  • Legal Information
  • Privacy Policy
  • Cookie Notice
  • Terms of use
  • Change your cookie settings