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IO-Link with Bihl+Wiedemann: Easy, Flexible & Cost-efficient

Advantages of IO-Link

IO-Link is an internationally standardized, manufacturer-independent interface. The open standard (IEC 61131-9) is compatible with all common fieldbuses when implemented with a gateway.

IO-Link with Bihl+Wiedemann

Multiple cost-savings

Using IO-Link Devices with solutions from Bihl+Wiedemann saves costs in many ways:


  • You only pay for as many IO-Link ports as you really need – because in addition to the 4-port IO-Link master we also offer you IO-Link masters with 1 and 2 ports
  • The amount of effort required for cabling is reduced because all participants – IO-Link devices, standard sensors and safety modules – are connected to an unshielded 2-wire cable using piercing technology
  • You can integrate significantly more IO-Link masters per Ethernet node and benefit from freely selectable topology as well as the elimination of switches and pre-assembled cables
  • Thanks to the integrated OPC UA server in our gateway, you can transfer process and diagnostic data of IO-Link devices to the Cloud in an easy and cost-efficient manner. This means you are well prepared for industry 4.0 applications, such as predictive maintenance.

Simply user-friendly

Our goal is to offer you a top user-friendly solution for IO-Link:


  • You can easily integrate IO-Link devices where you need them. In our wiring system, the maximum IO-Link cable length of 20 meters plays a subordinate role because you can distribute the IO-Link masters anywhere on the AS-Interface using cables up to 200 meters in length
  • You can combine our IO-Link masters optimally with IO-Link devices from various manufacturers
  • You benefit from easy integration of the IO-Link master via our configuration tool, e.g. by simply loading the IODD and by supporting sensor parameterization with graphics

What makes IO-Link integration with Bihl+Wiedemann unique?

1-port IO-Link master; no "unused" IO-Link ports

IO-Link devices are widely distributed in many systems. But the maximum cable length between an IO-Link master and IO-Link device is 20 meters. This is no problem with Bihl+Wiedemann. With our compact IO-Link masters with 1 or 2 ports, you can also easily connect individual IO-Link devices at any location – distributed over the AS-Interface cable length of up to 200 meters. The "smallest" modules of other manufacturers usually have at least 4 IO-Link ports. In practice, this often leads to "unused" IO-Link ports. Because if there are only 2 IO-Link devices within a radius of 20 meters, you would still have to pay for the 4 IO-Link ports of the "small" IO-Link master.

Compact Transmission of IO-Link Signals

With Bihl+Wiedemann, the IO-Link masters are not individually connected to the PLC. Instead, our ASi-5/ASi-3 gateway combines all signals of the IO-Link devices and transmits them compactly to the PLC. Bihl+Wiedemann IO-Link modules are significantly cheaper than comparable PROFINET devices. Our gateways, which are necessary for an installation, pay for themselves using only 3 IO-Link masters with 4 ports each. Another advantage of the gateway is the integrated OPC UA interface. It enables the process and diagnostic data of the IO-Link devices to be transferred to the Cloud in an easy and cost-efficient manner – a prerequisite for predictive maintenance.

IO-Link solution from Bihl+Wiedemann

IO-Link solution from other manufacturers

The big cost comparison – IO-Link with Bihl+Wiedemann

In many application scenarios, IO-Link solutions from Bihl+Wiedemann are much more cost-efficient than similar solutions from other providers. An application with Bihl+Wiedemann is already cheaper than comparable PROFINET variants from three 4-port IO-Link masters. Another factor is the finer granularity. Our 1-port IO-Link master allows you to integrate an IO-Link device exactly where you need it. Thanks to cable-piercing technology, it is extremely easy to install our IO-Link master. You can substantially reduce the time required for assembly.

The larger your application, the more you save

The more devices you need for your control system, the greater your cost advantage when you choose an IO-Link solution from Bihl+Wiedemann. For example, in a medium-sized application with 50 IO-Link devices, you can save up to 40 %* against a comparable PROFINET, EtherNet/IP or EtherCAT version.


With 50 devices*, you can save up to 40 %


Average cost savings* in %

*based on average list price of € 300 per 4-port IO-Link master

IO-Link cost comparison in detail

The price comparison is based on the following assumptions:

  • Only 4-port IO-Link masters with 4 ports each are used or compared.
  • IO-Link devices (sensors or actuators) can only be connected using an IO-Link master. A maximum of 4 IO-Link devices can therefore be connected to a 4-port IO-Link master. Therefore, three 4-port IO-Link masters with a total of 12 ports are required to connect 10 IO-Link devices.
  • The price comparison based on list prices does not take discounts into account. These must be included for exact cost comparison.
  • Further cost savings through to the simple AS-Interface wiring system are not included in the price comparison.

IO-Link integration with Bihl+Wiedemann:

Calculation of a Bihl+Wiedemann setup with 10 IO-Link devices:

Reduce additional costs by connecting digital I/Os directly

IO hubs and IO-Link master ports are often used to collect many digital I/Os – there is great saving potential in this respect. Simply use a Bihl+Wiedemann ASi-5 self-configuring I/O module: The 16 digital signals of the BWU4230 can be distributed freely as inputs or outputs – and can be connected without having to pass through IO-Link. By simply integrating digital I/Os via ASi, you do not need any additional IO-Link master ports just for standard signals. At the same time, you eliminate the need for the M12 connection cable between IO-Link I/O hubs and IO-Link master ports. The maximum IO-Link cable length of 20 meters is also irrelevant. That's because piercing technology enables you to distribute the digital I/Os anywhere along the ASi line with a length of up to 200 meters. Here you can find additional information about the ASi-5 self-configuring 16 I/O module.

Advantages of the Self-configuring I/O Modules

  • Sensors and actuators can be connected in any combination; offering you the possibility of having 2 signals per M12 connection
  • An optional assignment of a fixed configuration of inputs and outputs is also possible using our software
  • No M12 ports go unused thanks to a product portfolio that offers options from 4 I/Os to 16 I/Os
  • 16 inputs/outputs with ASi-5 in 1.27 ms
  • Cost-effective and fast collection of many inputs and outputs
  • Various connection types – the ASi/AUX connection is made via


More information

Save costs with your IO-Link application

IO-Link Products

ASi-5 Module with integrated IO-Link Master with 4 Ports, IP67

  • Convenient parameter assignment via Bihl+Wiedemann software suites
  • Transmission of up to 4 × 16 Bit Process Data in 1,27 ms
  • Up to 32 bytes of cyclic process data
  • 4 × IO-Link Ports, e. g.:

ASi-5 Module with integrated IO-Link Master with 4 Ports, IP20

  • Convenient parameter assignment via Bihl+Wiedemann software suites
  • Transmission of up to 4 × 16 Bit Process Data in 1,27 ms
  • Up to 32 bytes of cyclic process data
  • 4 IO-Link Ports (BWU3843)

Active Distributor
ASi-5 / IO-Link Master

  • Convenient parameter assignment via Bihl+Wiedemann software suites
  • Transmission of up to 4 × 16 Bit Process Data in 1,27 ms
  • Up to 32 bytes of cyclic process data
  • 1 IO-Link Port Class A (BWU4748), Power supply of IO-Link ports out of ASi
  • 1 IO-Link Port Class B (BWU4088)

  • 2 IO-Link Ports, e. g.: 1 IO-Link Port Class A, 1 IO-Link Port Class B (BWU4077)

ASi-5/ASi-3 Gateways with Safety Monitor

  • Compatible with existing networks

  • 1.27 ms cycle time for up to 384 input and 384 output bits
  • Most powerful platform by Bihl+Wiedemann
  • ASi Safety integrated
  • Safe fieldbus protocol

ASi-5/ASi-3 Gateways in Stainless Steel

  • Compatible with existing networks
  • 1.27 ms cycle time for up to 384 input and 384 output bits
  • Cost-effective solution for all standard applications from Bihl+Wiedemann
  • Feldbus systems, e. g.:

StarterKit ASi-5 / IO-Link

(BW4211, BW4229)

  • Set consisting of:
    • 24 Volt ASi-5/ASi-3 PROFINET Gateway (BWU3847) or 24 Volt ASi-5/ASi-3 EtherNet/IP + Modbus TCP Gateway (BWU3849), also Gateways to other fieldbus systems selectable
    • ASi-5 Module with integrated IO-Link Master with 4 Ports, IP67, M12 (BWU4067)
    • ASi Substructure Module in IP67, 45 mm (BWU2349)
    • Bihl+Wiedemann Software Suite for Configuration, Diagnostics and Commissioning (BW2902)

  • Starter kit is shipped fully assembled and wired in a convenient case
  • Cost-effective version for starting with ASi-5
  • Sufficient space for installing your own IO-Link sensor

Compatible with all common fieldbuses

  • EtherNet/IP + ModbusTCP
  • EtherCAT
  • Sercos


Safe fieldbus protocols are supported

  • PROFIsafe
  • CIP Safety
  • Safety over EtherCAT


Jochen Bihl explains why ASi and IO-Link are ideal partners on the field level. With ASi-5 Module with integrated IO-Link Master by Bihl+Wiedemann you can incorporate intelligent IO-Link sensors and actuators into ASi – right where they are located.

Video length: 2:58

Jochen Bihl introduces the ASi-5 Module with integrated IO-Link Master with 4 ports from Bihl+Wiedemann. The ASi-5 module can transmit up to 32 bytes of I/O cyclic data – which fits IO-Link perfectly. By default the modules transmit over AS-i a total of 8 bytes – 2 bytes per port – in 1.27 ms.


Video length: 2:39

IO-Link is an integral part of ASi-5. Paul Werge, Product Manager at Bihl+Wiedemann presents the new ASi-5 Module with inetgrated O-Link Master at Hanover Fair 2019. The new ASi-5 Module with integrated IO-Link Master is able to integrate any IO-Link devices into ASi. Up to 32 bytes of process data can be configured.


Video length: 1:43



Integrating IO-Link into an AS-Interface Network

  • The IO-Link Master is incorporated into the ASi network as an ASi node
  • IO-Link devices can be integrated into the ASi network together with standard sensors / actuators and safety components
  • Process data from the IO-Link sensors, such as exceeding a switching threshold, are made available via the cyclical ASi communication
  • Diagnostics information available over ASi from IO-Link

Integrating the IO-Link Master Using our Configuration Tool

  • Simply access the IODD (IO Device Description) using the IO-Link configurator in ASIMON360 (BW2916, BW3065, BW2902)
  • Graphic support for configuring the connected sensors
  • Single parameters can be read or written to the IO-Link sensor over the ASi bus

IO-Link Safety solutions from Bihl+Wiedemann

IO-Link Safety is an extension of IO-Link. There is an additional safety communication layer on the master and device side. These become the "Fail-Safe (FS) master" and "Fail-Safe (FS) device". Bihl+Wiedemann is in the process of developing its own "FS master". IO-Link is already a perfect match for the safety components of Bihl+Wiedemann.

FAQs about IO-Link

The open IO-Link interface requires only a simple standard industrial cable. Intelligent sensors and actuators can be connected in a cost-efficient manner on an unshielded three- or five-wire cable. For point-to-point communication, each IO-Link device needs an IO-Link master.

The IO-Link master handles the communication to the intelligent sensors and actuators. It enables parameterization, diagnostics and access to the cyclic data by means of a connection to the control system.

Reduced machine-related costs

A cost-efficient standard cable establishes a connection up to 20 meters long between the IO-Link master and IO-Link device.


High machine availability

Downtimes are reduced because when a defective IO-Link device is replaced, its parameters are automatically transferred to the new sensor by the IO-Link master or control system.


Efficient operation

IO-Link devices can be positioned in the machine directly at the work site. These do not have to be accessible for parameterization.


Demand-oriented maintenance

Continuous diagnostic data of the entire process lengthen maintenance intervals, since systems and machines need to be maintained much less frequently due to the automatic readjustment via IO-Link


More information about the advantages of IO-Link

No. IO-Link is a point-to-point connection between an IO-Link master and an IO-Link device (sensor or actuator). The connection's cable length can be up to 20 meters.

IO-Link is mainly used in industrial production automation for communication with sensors and actuators.

It is possible to extend existing bus systems. As a prerequisite, the system mapping of IO-Link for the respective bus system must be already implemented. It is particularly easy to use IO-Link in conjunction with the ASi intelligent wiring system. Thanks to piercing technology, corresponding IO-Link masters can be easily retrofitted where they are needed.

Do you have questions about IO-Link solutions from Bihl+Wiedemann?

We would be happy to assist you.


Contact us now