IO-Link 101: Ten Terms to Know

  1. IO-Link System
  2. An IO-Link system is comprised of sensors and/or actuators that support IO-Link (version 1.0 or 1.1) which are connected via a master, such as Comtrol offers. The master then will communicate to a controller (PLC, HMI, SCADA, etc.) through an industrial Ethernet protocol such as Ethernet/IP, Profinet IO or Modbus TCP.

    Comtrol exclusively allows the user to communicate through two industrial Ethernet protocols simultaneously; see MultiLink

  3. MultiLink™ – Comtrol Specific Benefit
  4. MultiLink™ provides the capability to simultaneously access multiple IO-Link controllers running different industrial Ethernet protocols.
    IO Link Ethernet Modbus - IO-Link 101: Ten Terms to Know

  • IODD: IO Device Description
  • Every IO-Link sensor/actuator has an IODD file which allows you to interact with the device on a web interface such as Comtrol’s. Each IO-Link device manufacturer will have these available via their website.

    With Comtrol’s IO-Link Master you can load and store a library (up to 15790K) of IODD files for your IO-Link devices onto the Comtrol IO-Link Master so that you can configure the IO-Link sensors or actuators from the IO-Link Master web interface.

  • Data Types: Process, Service, Event
  • Three types of data are visible with IO-Link: Process Data, Service Data and Event Data.

  • Remote Parameterization
  • The Comtrol IO-Link Master supports remote communication from a PLC and/or HMI to an IO-Link device so that you can change an IO-Link device’s configuration or operational behavior.

    In addition, you can change an IO-Link device’s configuration using the Comtrol IO-Link Master web interface without a PLC or HMI.

  • Auto-Device Replacement (ADR)
  • Allows an IO-Link device to be automatically configured using previously stored values. Quick and easy replacement of failed or damaged sensors or actuators which means reduction in production line downtime and maintenance costs.

    Example: Company A has IO-Link v1.1 sensors deployed and configured with Auto-Device Upload/Download feature enabled in Comtrol’s web interface. If an IO-Link device fails, they can replace it with a factory default device of the same type and can be up and running much sooner.

  • IO-Link Master web interface
  • Comtrol offers a web interface unlike any other in the IO-Link Master marketplace. It provides extensive benefits to make using an IO-Link Master as easy as possible.

  • IO-Link Device Validation
  • Using IO-Link Device Validation makes your IO-Link master ports intelligent. You can link IO-Link ports to operate only when a compatible or identical IO-Link device is attached.

    Example: If a plant or controls manager wants specific devices to only work on certain ports, they can achieve this. Therefore if maintenance is done or devices are frequently disconnected then reconnected, you can ensure the right devices are on the proper ports. A red LED light will flash on the master if the wrong device is connected. You will also see this Event Data flag on Comtrol’s web interface.

  • ISDU: Index Service Data Unit
  • Comtrol offers ISDU Handling which is when the IO-Link Master handles all programming to provide PLC access to IO-Link device ISDU blocks with a flexible and simplified interface – provides multiple or single ISDU command message support and blocking and non-blocking messaging methods. The PLC ISDU message format is designed for flexibility and ease of use. Each message can contain a single command, multiple commands with the same data area size, or with commands with varying data area sizes.

    ISDUHandlingdiagram - IO-Link 101: Ten Terms to Know

  • Data Validation (Strict or Loose)
  • Use the Data Validation option to ensure data integrity by defining the PDI and/or PDO length. Also gives the user the ability to see that data is successfully being communicated to the master.