IO-Link Signalling Devices
Industrial signalling devices provide visual and acoustic indication of machine states, process conditions, warnings and alarms. Pfannenberg’s IO-Link signalling solutions extend conventional status indication by enabling signalling parameters, operating modes and diagnostic information to be managed through the automation system.
What Is IO-Link Signalling?
IO-Link enables signalling devices to exchange process and device data with the machine control architecture instead of functioning solely as individually wired outputs.Â
Depending on the device, parameters such as colour, brightness, flashing frequency, signalling mode and acoustic signals can be configured through software.
This makes the signalling device part of the connected automation architecture and provides additional information for commissioning, monitoring, maintenance and diagnostics.
Why use IO-Link Signalling?
- Centralized parameterization – configure signalling behaviour through the control system.
- Real-time diagnostics – access device status and diagnostic information.
- Flexible signalling – adjust colours, brightness, flashing patterns or tones depending on the device.
- Simplified installation – standardized connection technology reduces wiring complexity.
- Faster device replacement – parameters can be retained and transferred through the IO-Link architecture.Â
Questions on signalling?
Our sales engineers would love to help you pick the right
signalling technology for your solution.
Our assortment of IO-Link devices
Intense Bar S
The Pfannenberg INTENSE Bar S is a compact RGB LED status indicator designed for clear machine and process status signalling.Â
With IO-Link, colours, brightness, flashing frequencies, and signalling modes can be configured through the automation system.
Intense Bar S Specifications:
- Length : 160mm
- Operating range: 21-30 V
- Light intensity: 9 cd
- Operating modes: continous, blinking, flashing light
- Operating temperature: –20 °C to +50 °C
- IP54
- Multiple selectable LED lights
Pfannenberg
Pfannenberg
Intense Bar M
The Pfannenberg INTENSE Bar M provides a larger visual signalling surface for communicating machine and process conditions across automated systems.Â
IO-Link integration enables signalling parameters such as colour, light intensity, and flashing behaviour to be remotely adjusted and managed through the control system.
Intense Bar M Specifications:
- Length : 316mm
- Operating range: 21-30 V
- Light intensity: 30 cd
- Operating modes: continous, blinking, flashing light
- Operating temperature: –20 °C to +50 °C
- IP54
- Multiple selectable LED lights
Intense Dome 50
The Pfannenberg INTENSE Dome 50 is a compact RGB LED signalling device for displaying machine and process conditions from multiple viewing angles.
IO-Link enables centralized control and adjustment of signal colours, brightness, and flashing behaviour, allowing the indication to be adapted to different operating states.
Intense Dome 50 Specifications:
- Operating range: 21-30 V
- Light intensity: 10 cd
- Operating modes: continous, blinking, flashing light
- Operating temperature: –20 °C to +50 °C
- IP67 & IK07
- Multiple selectable LED lights
Pfannenberg
Pfannenberg
Radial LED and Sounder PA L 1-R
The optional IO-Link version enables intelligent parameterization of signalling modes through the automation system, providing greater flexibility in how different operating states are indicated.
PA L 1-R Specifications:
- Voltage options: 12-48 V DC | 115/230 V AC | 24/48 V AC
- Combined light and sound signalling
- Sound Intensity: 105 dB(A)
- Light Intensity: 16 cd
- Max viewing distance: 93m
- Flashlight, Blinking, Continuous, and Rotating light modes
- Operating temperature: –25 °C to +50 °C
- IP66, NEMA 4/4X, IK 07
- Multiple LED light options
Intense BR 50 IO-Link Module
The Pfannenberg BR 50 IO-Link modules provide the communication interface for connecting modular BR 50 signal towers to IO-Link-based automation systems.
Available as a standalone module or with a pre-installed M12 base connection, they enable centralized control and configuration of connected BR 50 signalling components.
IO-Link Module Specifications:
- Rated Voltage: 24 V DC
- Maximum number of modules: 4
- Tower diameter: 54mm
- Compatible with LED, flashing, and sounder modules
- Operating temperature: −25 °C to +50 °C
- IP54, IP65 (optional)
- M12 Base (optional)
Intense BR 50 IO-Link Module
The Pfannenberg BR 50 IO-Link modules provide the communication interface for connecting modular BR 50 signal towers to IO-Link-based automation systems.
Available as a standalone module or with a pre-installed M12 base connection, they enable centralized control and configuration of connected BR 50 signalling components.
IO-Link Module Specifications:
- Rated Voltage: 24 V DC
- Maximum number of modules: 4
- Tower diameter: 54mm
- Compatible with LED, flashing, and sounder modules
- Operating temperature: −25 °C to +50 °C
- IP54, IP65 (optional)
- M12 Base (optional)
Practical applications of IO-Link Signalling
IO-Link signalling connects machine and process status indication directly with the automation system, enabling clear local signalling alongside centralized control and communication. Each signalling device offers specific functions and practical advantages, allowing the solution to be matched efficiently to different machine, process, and installation requirements.
When is the best time to use each device?
Intense Bar S
Intense Bar M
Intense Dome 50
PA L 1-R
BR 50 + IO-Link module
IO-Link signalling can be applied to a wide range of applications, including:
Machine Status and Warning Indication
IO-Link signal lights, signal towers and sounders can communicate machine conditions such as normal operation, warnings, faults and maintenance states. Configurable colours, flashing patterns and acoustic signals help operators quickly recognize conditions that may require attention.
Maintenance and Troubleshooting
IO-Link can provide device status and available diagnostic information to the control system, helping maintenance teams identify signalling-device issues and locate faults more efficiently. Parameter storage can also simplify compatible device replacement and recommissioning.
Automation and Safety Zones
On automated machines, production lines and robotic cells, IO-Link signalling devices can provide clear indication of operating modes, restricted-area conditions, machine stops or required operator intervention. They can complement the machine safety system by improving awareness, while the actual safety functions remain handled by appropriate safety-rated devices and controls.
Frequently Asked Questions about IO-Link Signalling
A conventional signalling device is typically controlled using individual digital outputs from a PLC for functions such as lights, colours or audible signals. An IO-Link signalling device uses digital point-to-point communication through an IO-Link master, allowing signalling functions to be controlled and configured while also supporting bidirectional data exchange.
Depending on the device, IO-Link can provide configurable colours, brightness, flashing patterns, audible signals, operating modes and diagnostic information without requiring separate control wiring for every function.
The configuration options depend on the individual IO-Link signal light, signal tower or sounder. Typical parameters can include:
- Signal colours
- LED brightness
- Flashing or blinking frequency
- Individual signal tower segments
- Operating modes
- Audible tones
- Sound level
For example, IO-Link signal towers can allow individual segments, colours, brightness and flashing behaviour to be configured through IO-Link. The exact parameters available for a specific device are defined in its IODD (IO Device Description).
Yes, an IO-Link master is required to establish IO-Link communication with an IO-Link signalling device. The signalling device connects to an IO-Link port on the master, which provides the interface between the IO-Link device and the higher-level automation system.
Some IO-Link devices can additionally operate in SIO (Standard Input/Output) mode, but this is device-specific and does not provide the full IO-Link communication functionality.
A standard PLC digital output does not provide the IO-Link communication interface. However, if a PLC or remote I/O system has integrated IO-Link master ports, the signalling device can connect to one of those ports without requiring a separate external IO-Link master.
IO-Link is a point-to-point communication technology rather than an industrial fieldbus.
Yes. IO-Link provides bidirectional communication, meaning information can travel both to and from an IO-Link device.
In addition to receiving commands from the control system, an IO-Link signalling device can provide device identification, status, events and diagnostic information when these functions are supported by the device. This information can be used by the PLC, HMI or maintenance system for monitoring and troubleshooting.
No. An IO-Link device does not require its own IP address for communication with an IO-Link master.
IO-Link uses a point-to-point connection between each device and an individual IO-Link master port. The IO-Link master may communicate with the PLC over an Industrial Ethernet network and therefore have its own network configuration, but the individual IO-Link signal light, sensor or actuator does not need an Ethernet IP address for its IO-Link connection.
IODD stands for IO Device Description. It is the standardized device-description information associated with an IO-Link device.
An IODD describes information such as:
- Device identification
- Configurable parameters
- Process data
- Diagnostic data
- Communication characteristics
The IODD allows engineering and configuration software to understand the capabilities and parameters of a particular IO-Link device, simplifying configuration, commissioning, diagnostics and maintenance.
Every IO-Link device type must have an associated IODD provided by the device manufacturer. The IO-Link specification explicitly requires an IO-Link device to provide an associated IODD file.
You do not need to create an IODD yourself. Manufacturers provide these files, and they can also be made available through the IO-Link IODDfinder. Multiple identical signalling devices use the corresponding IODD for that device type rather than requiring a separately created file for every physical unit.
Not necessarily. IO-Link supports data storage and parameter management that can simplify the replacement of compatible devices.
When the IO-Link master and device support the appropriate data-storage functionality and the system is correctly configured, stored parameters can be transferred to a replacement device. This can reduce manual configuration and help shorten machine maintenance and commissioning time.
The exact replacement procedure depends on the IO-Link master, device and system configuration, so compatibility should be checked before relying on automatic parameter restoration. Data Storage is specifically covered by the IO-Link test specification.
IO-Link is standardized according to IEC 61131-9. The standard covers the single-drop digital communication interface used for communication with sensors and actuators. The IO-Link Community describes IO-Link as the first globally standardized I/O technology for this purpose.
An IO-Link signalling device may also need to meet additional standards and regulatory requirements depending on the product and application. These can relate to electrical safety, EMC, environmental protection, visual or audible signalling, machinery requirements and functional safety.
Standard IO-Link should also not automatically be treated as a safety communication system. IO-Link Safety is a separate extension specifically developed for safety-related communication.
Therefore, compliance with IEC 61131-9 does not by itself establish that a signal tower, signal light, sounder or complete machine complies with all applicable machinery or functional-safety requirements.
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