IO-Link is the first standardized IO technology worldwide (IEC 61131-9) for the communication with sensors and also actuators. The powerful point-to-point communication is based on the long-established 3-wire sensor and actuator connection without additional requirements regarding the cable material. So, IO-Link is no fieldbus but the further development of the existing, tried-and-tested connection technology for sensors and actuators.

IO-Link Network Diagram.png

Frequently Asked Questions

Why is IO-Link needed?

O-Link is needed because: - It closes the communication gaps at the lowest field level. - It renders machines and systems capable of validation right down to the lowest sensor and actuator level. - It minimizes interfaces (PNP, PushPull, 4-20 mA, 0-10 V, RS232, RS422 become IO-Link).

Is IO-Link another fieldbus?

ny individual connection can be extended to a maximum of 20 m.

How fast is signal transmission via an IO-Link connection?

he typical signal transmission time for a value of up to 16 bits in length is 2 ms.

What data are transmitted using IO-Link?

User data (e.g., analog values, switching states) are cyclically transmitted, configuration data (e.g., activation, deactivation of functions) and identification data (manufacturer identifier) typically during start-up and parameters (sensitivity, switching threshold) on a demand-driven basis.

Which sensors without IO-Link capability can be connected to an IO-Link (master)?

Standard PNP outputs or PushPull outputs.

Is mixed operation of IO-Link and conventional devices possible?

Both device types can be operated on a mixed basis within one system.

What changes in terms of installation and application?

In terms of wiring technology, everything remains the same. NPN sensors cannot be connected to IO-Link. All previously known communication structures in higher-level systems do not change.

Is the system simpler than known communication structures?

Higher-level communication structures are generally bus systems. IO-Link is a point-to-point connection.

What must be observed when wiring?

Standardized 3-wire connecting cables or single strands in the switch cabinet are used. No shielding is required.

What type of connectors are required on the sensor side?

No special IO-Link connectors or cables are required. The recommended minimum cross sections must be adhered to. For 20 m cable lengths the minimum cross section is 0.34 mm². As unshielded cables can be used, M8 and M12 standard connectors are certainly the most commonly used.

Is it possible to transmit safety-relevant data such as emergency stop commands via IO-Link?

The transmission of safety-relevant data is not planned at present.

What happens if an IO-Link proximity switch is defective and an identical replacement is not available?

An IO-Link proximity switch (a switching output) can also be exchanged with a corresponding standard proximity switch. Automatic identification, reconfiguration and other communication capability-related functions are then not available. In this case, only the switching signal is transmitted.

How is voltage disconnection achieved for drive systems?

The potential-free contact is achieved using pin 2 and pin 5. For this purpose, a 5-pin standard cable is to be used.

How is IO-Link positioned?

IO-Link is typically used in an automation environment below the I/O level for individual linking of field devices.

Where is IO-Link used?

IO -Link is used predominantly in an industrial environment in automated production for linking sensors and actuators.

What setting options do I have with IO-Link capable sensors and actuators?

This depends on the possibilities implemented by the manufacturer, but in general: - Local operation using teach-in, setting potentiometers, etc. - Event-driven program running using a connected controller. - Operator-driven program running, e.g. using an HMI interface. - Engineering system. - Installation of a sensor in a pre-planned automation station with stored basic sensor settings. This also enables dynamic changing of parameter settings. Automated new settings are also possible.

How does IO-Link function?

IO-Link is based on the familiar 3-conductor connection for a digital switching signal, in which the switching signal is issued as a serial telegram. This means additional information can be exchanged in the form of a serial protocol between the I/O level and the field device.

What is IO-Link?