MODBUS - Connect any Device with UniCloud

UniCloud can access PLCs and other devices that support Modbus via UCR routers.

To enable this, follow the simple steps listed below, which are described in detail in the next sections:


Generate a Unique MODBUS Serial Number

  1. Click Device Management > PLC Management > Add PLC to open the New PLC window.


  1. Click the PLC type > drop-down arrow, and select Modbus.


  1. Click Generate to create a unique ID number.
    Copy this ID number to your clipboard or make a note of it. You will use it when you create the Asset; this is the unique ID number that UniCloud will use to communicate with the device.



  1. Click Add, and then click Close; the Unique ID number has been added to UniCloud, and can be used to create an Asset.


UniCloud: link the Modbus device to a UCR Router

  1. In Device Management> Router Management, click the UCR Router you want to link to the Modbus device; the Router Details open.

  2. Select the PLC tab, and then click Add.

  3. Enter the serial number  you generated for the Modbus device, and click Validate; the Modbus device is listed in the PLCs tab.

  4. Click Close.

UCR Router: Create a MODBUS Slave

  1. In the UCR Router Program enter Services > UniCloud > PLC.

  2. Under New PLC, enter a name in the Name field and then click Add.

  3. The Advanced PLC Settings window opens:

    1. In the Serial Number field, paste or enter the unique ID number you generated.

    2. In the PLC Model field, click the drop-down arrow and select Modbus Slave.

    3. Enter or edit the rest of the settings according to your requirements:

    4. Click Save.

You can also enable secure Remote Access via VPN to the device:

  1. Check Select Allow Secure Remote enable VPN to access the device ports.

  2. Enter port numbers, up to five ports can be defined, separated by a comma

UCR Router: Create a MODBUS Asset Type

  1. Select the Assets tab. Under Create new Asset type, enter the Asset Type name and then click Add; this opens the Advanced Asset Type Settings.

  2. Click Add new Tag. Since UniCloud identifies this as a Modbus Slave type, Modbus addressing opens
    Define the desired tags.
    Ensure that you use the exact byte order required by your Modbus device.
    You can also add Alarms if desired.
    When you are done, click Sync & Save UniCloud to add the Asset Type to UniCloud and enable you to create the Asset.

  3. The new Asset Type is listed in UniCloud> Device Management> Asset Management> Asset Types, and can be published

UniCloud: Creating the Asset

  1. In  UniCloud> Device Management> Asset Management> Assets, click Add to open the New Asset window.

  2. Select the Asset Type, enter/paste in the serial number you generated previously, and click Validate..

  3. Name the Asset. You can also enter an asset serial number of your own. Click Save.

  4. The Download Certificate window opens, click Download

  5. UCR Router: click the Certificates tab.

    1. Click Choose, and navigate to and select the certificate file.

    2. Click upload to certify the Modbus device.

The Modbus device is now in the Asset list, and is ready to be assigned a subscription.