Rockwell Automation Allen-Bradley 856T-B24LC User manual

Control Tower IO-Link Class B
Light and Sound Module
Controller
Catalog Number 856T-B24LC
User Manual Original Instructions

2Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Control Tower IO-Link Class B Light and Sound Module Controller User Manual
Important User Information
Read this document and the documents listed in the additional resources section about installation, configuration, and
operation of this equipment before you install, configure, operate, or maintain this product. Users are required to familiarize
themselves with installation and wiring instructions in addition to requirements of all applicable codes, laws, and standards.
Activities including installation, adjustments, putting into service, use, assembly, disassembly, and maintenance are required to
be carried out by suitably trained personnel in accordance with applicable code of practice.
If this equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be
impaired.
In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use
or application of this equipment.
The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and
requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for
actual use based on the examples and diagrams.
No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software
described in this manual.
Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation, Inc., is
prohibited.
Throughout this manual, when necessary, we use notes to make you aware of safety considerations.
Labels may also be on or inside the equipment to provide specific precautions.
WARNING: Identifies information about practices or circumstances that can cause an explosion in a hazardous environment,
which may lead to personal injury or death, property damage, or economic loss.
ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property
damage, or economic loss. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence.
IMPORTANT Identifies information that is critical for successful application and understanding of the product.
SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous
voltage may be present.
BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may
reach dangerous temperatures.
ARC FLASH HAZARD: Labels may be on or inside the equipment, for example, a motor control center, to alert people to
potential Arc Flash. Arc Flash will cause severe injury or death. Wear proper Personal Protective Equipment (PPE). Follow ALL
Regulatory requirements for safe work practices and for Personal Protective Equipment (PPE).

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 3
Table of Contents
Preface
Who Should Use This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Download Firmware, AOP, EDS, and Other Files . . . . . . . . . . . . . . . . . . . . 7
Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Chapter 1
Product Overview Operation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Product Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
IO-Link Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Chapter 2
IO-Link Overview What is IO-Link? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Why IO-Link?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Seamless Integration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Real-time Diagnostics and Trending . . . . . . . . . . . . . . . . . . . . . . . . . . 14
IO-Link Device Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Device Profiles and Automatic Device Configuration. . . . . . . . . . . . 14
Descriptive Tags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
How IO-Link Works? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Transmission Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Transmission Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Response Time of the IO-Link System . . . . . . . . . . . . . . . . . . . . . . . . . 15
IO-Link Data Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Process Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Value Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Device Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Access IO-Link Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Cyclic Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Acyclic Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
I/O System Startup. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Assign Device Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

4Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Table of Contents
Chapter 3
Configure the 856T-B24LC IO-
Link Module
Products Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Hardware. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
AOP Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Create Project . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Add Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Add POINT I/O Ethernet Adapter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Add IO-Link Master . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Register the 856T-B24LC Module IODD File . . . . . . . . . . . . . . . . . . . . . . . 24
Embedded IODD File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Download IODD File. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Connect the 856T-B24LC Module to the IO-Link Master. . . . . . . . . . . . . 29
Download the Project to the PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Chapter 4
IO-Link Parameters Display Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
IO-Link Tabs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Common Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Identification Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Observation Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Parameter Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Diagnosis Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Chapter 5
Power On Self Test (POST) Hardware Fault Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Non-recoverable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Critical . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Severe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Device Status Indicator -Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
IO-Link Status Indicator Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Chapter 6
Class A IO-Link Master
Connection Consideration
Patchcord . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Maximum Number of Light/Sound Modules in the Stack Light . . . . . . 45
Inrush Current Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Overcurrent Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chapter 7
Message Structure and
Configuration Example
Configure a Message Instruction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Example Format of a Read Message. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Read Data from the IO-Link Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Example Format of a Write Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Validation of Write. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Service Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Source Length: From Data Structure Tables . . . . . . . . . . . . . . . . . . . . 52

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 5
Table of Contents
Appendix A
Specifications IO-Link Module Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Approximate Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Appendix B
IO-Link Operation Modes of 856T
Light and Sound Modules
856T Light and Sound Module Operation Mode . . . . . . . . . . . . . . . . . . . . 55
Appendix C
Device Parameters Identification Tab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Observation Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Parameter Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Diagnostics Tab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
IO- Link System Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Process Data Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Process Data Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Configuration Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Appendix D
Device Status Operational State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Short Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Appendix E
Factory Reset Reset to Factory Settings — Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Reset All Statistics —Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Appendix F
Troubleshooting Error Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77

6Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Table of Contents
Notes:

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 7
Preface
This manual is a reference guide for the 856T-B24LC IO-Link module for
Control Tower™ stack lights. It describes the procedures to install, wire, and
troubleshoot this device.
Who Should Use This
Manual
Use this manual if you design, install, program, or troubleshoot systems that
use the 856T-B24LC module for stack lights.
You must have a basic understanding of electrical circuitry and familiarity
with safety-related systems. If you do not, obtain the proper training before
using this product.
Qualified personnel must conduct all inspections. A qualified person must
perform these tasks:
• Undergone the appropriate technical training
• The responsible machine operator has instructed personnel in the
operation of the machine and the current safety guidelines.
• Has read and has access to the user manual.
Abbreviations
Download Firmware, AOP,
EDS, and Other Files
Download firmware, associated files (such as AOP, EDS, and DTM), and access
product release notes from the Product Compatibility and Download Center at
rok.auto/pcdc.
Abbreviation Description
ADC Automatic Device Configuration
AOI Add-On Instruction
AOP Add-On Profile
ASN Application-Specific Name
IEC International Electrotechnical Commission
IOOD I/O Device Description
NEC National Electric Code
QD Quick disconnect
RGB Red, green, blue
SIO Standard I/O
IO-Link module
Tower light IO-Link Class B light and sound module controller856T-B24LC
IOLD
POST IO-Link module power on self test

8Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Preface
Additional Resources These documents contain additional information concerning related products
from Rockwell Automation.
You can view or download publications at rok.auto/literature.
Resource Description
Bulletin 856T Control Tower Installation Instructions, publication 856T-IN013 Provides information to install and wire the 856T IO-Link module.
System Security Design Guidelines, publication SECURE-RM001 Provides guidelines for how to use Rockwell Automation products to improve the security of
your Industrial Automation system.
Industrial Automation Wiring and Grounding Guidelines, publication 1770-4.1 Provides general guidelines for installing a Rockwell Automation industrial system.
Product Certifications website, rok.auto/certifications. Provides declarations of conformity, certificates, and other certification details.

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 9
Chapter 1
Product Overview
The 856T-B24LC module allows the control and configuration of a standard
856T stack light via the IO-link protocol. This configuration helps your save
time and money in wiring, commissioning, and startup of the entire stack
light while providing access to valuable real-time diagnostics and prognostic
information.
Operation Modes The 856T-B24LC module is compatible with the current light and sound
modules that are offered in the standard 856T product line. The 856T-B24LC
module is capable to control up to seven modules in the stack light
arrangement. The maximum number of light and sound modules in a stack
light configuration depends on the number of circuits that are used
individually by the specific light or sound module (up to seven per 856T-B24LC
module). A summary of all 856T light and sound modules that can be controlled
with the 856T-B24LC module is shown in Table 12 on page 55.
Product Features • Mechanically compatible with all 856T base mount adapters to offer
vertical, surface, pole, and tube mounting options
• 70 mm external diameter
• Visible status indicator that shows the result of the device self test at
powerup.
• IP66/67 rated enclosure
• IO-Link 1.1 communication protocol compliant
• Class B device
IO-Link Features • Built-in counters to allow you to know the number of times a specific
module has been turned ON.
• Operation hours since inception and since powerup that can help you
correlate machine availability.
• Vibration indication to alert you about unusual mechanical behavior
when the IO-Link module detects vibration above certain threshold
values.
• Class A and Class B voltage monitoring
• Short-circuit detection to help protect the circuitry of the device and the
master from a light or sound module short circuit.
• Open load condition useful to indicate when light or sound modules in
the stack light have not been properly installed.
• Premier integration design that enables configuration via the
Rockwell Automation® IO-Link master Add-on Profile.
• Automatic Device Configuration that helps you replace the device
quicker, if necessary.

10 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 1 Product Overview
• Embedded IODD file in the device saves configuration time because
there is no need to find this file somewhere else. This file also makes
IODD registration quicker.
• Process Data Maps allow for selection of the type of information that is
continuously sent to the PLC as a process data parameter.
• Internal temperature indication that helps to understand changes in the
temperature of the application environment.
Installation
The 856T-B24LC module is mounted without the use of a tool in any of the 856T
standard base mount adapters that are shown in Figure 2.
For a good mechanical fit, the module provides a haptic feedback (click) only
when it is fully twisted onto the base mount adapter.
The 856T-B24LC module encloses the 5-pin M12 connector on the bottom of the
device and accepts standard cordsets to connect to an IO-Link Master Class B.
Figure 1 - Mount the IO-Link Module
IMPORTANT The 856T tower light product family (including the 856T-B24LC module)
is designed for general signaling applications and should not be wired
to any safety circuit in the application.
IMPORTANT Verify that the right edge on the alignment mark (triangle shape) in the
856T-B24LC module is aligned with the arrow mark on the base mount
adapter as shown in Figure 1.
IMPORTANT Physical protection of the stack light is recommended where the
possibility of unwanted access or damage to the device exists in the
application. You should also consider the use of conduit to shield the
cable to avoid cable or wiring cuts.
IMPORTANT Since the IO-Link protocol is not encrypted or authenticated, you should
protect the cabling and the connectors in both the IO-Link master and
the 856T-B24LC module to help prevent unwanted access when a
distributed control architecture is used. When the device is installed on
top of a control panel, the panel enclosure must provide protection
against unwanted accessibility to the cabling.
3
1
2
Click
Closed
856T-ABCAP
Not Supplied

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 11
Chapter 1 Product Overview
Figure 2 - Base Mounting Adapters
When power is applied to the device, the module runs a self-test routine to
verify the health of its internal electronic components and the result of this test
is visible via a bicolor status indicator that is mounted inside the module but
visible from the top. In addition, this status indicator also displays if the device
is communicating with the IO-Link Master. For more information on these
results, see Power On Self Test (POST) on page 43.
Figure 3 - Status Indicator Location on IO-Link Module
Pole mountVertical mountSurface with screwsSurface 1/2 in. NPT Threaded tube mount
856T – BMA P10
ab
ab
Housing Color Mounting Style
Code Description Code Description
BMA Black SN NPT surface mount, Type 4/4X/13
VM Vertical mount
SH Surface mount NPT, Type 4/4X/13, preinstalled mounting hardware
P10 10 cm (3.9 in.) aluminum pole mount
P25 25 cm (9.8 in.) aluminum pole mount
P40 40 cm (15.7 in.) aluminum pole mount
P60 60 cm (23.6 in.) aluminum pole mount
T10 10 cm (3.9 in.) threaded tube (M20)
T25 25 cm (9.8 in.) threaded tube (M20)
Status
Indicator

12 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 1 Product Overview
Wiring The 856T-B24LC module has an embedded 5-pin M12 connector at the bottom
of the unit. This connector accepts standard cordsets when connecting the
device with a Class B Master. Figure 4 shows the pin arrangement.
Figure 4 - M12 Connector Location and Pin Arrangement
Figure 5 - Connection Example: 856T-B24LC Module to the 1734-4IOL Master
IMPORTANT See Class A IO-Link Master Connection Consideration on page 45 for
specific considerations when connecting the 856T-B24LC module to an
Allen-Bradley Class A IO-Link master.
Table 1 - Wiring the 856T-B24LC Module to the 1734-4IOL Master
856T-B24LC Module 889D Cordset
Wire Color 1734-4IOL Connection
M12 Connector Pin # Signal
1 L+ Brown Voltage
2P24White—
3 L- Blue Common
4 C/Q Black Channel
5N24Gray—
M12 Connector
5
2
1
4
3
Pin Signal Description
1 L+ Power supply (+)
2 P24 P24 (port Class B)
3 L- Power supply (-)
4 C/Q SIO/SDCI
5 N24 N24 (port Class B)
Class B
M12-5
1734-4IOL
Point I/O Adapter
NC
0
NC
1
Chas
Gnd
2
Chas
Gnd
3
C
4
C
5
V
7
V
6
Ch 0
0
Ch 1
1
Ch 2
2
Ch 3
3
C
4
C
5
V
7
V
6
Black
Blue
Brown
N24 Gray
P24 White
Device
Power
Supply
-
+
IMPORTANT Use an 889D-F5AC-* cordset to connect the 856T-B24LC module
to the 1734 IO-Link master.

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 13
Chapter 2
IO-Link Overview
What is IO-Link? The IO-Link technology is an open point-to-point communication standard
and was launched as (IS) IEC 61131-9. IO-Link is now the first globally
standardized technology for sensor and actuator communication with a
fieldbus system. This technology provides benefits to both OEMs and end
users.
IO-Link provides communications-capable sensors to the control level by a
cost-effective point-to-point connection. IO-Link provides a point-to-point
link between the I/O module and device that is used for transferring detailed
diagnostics, device identity information, process data, and parameterization.
IO-Link communication is based on a master-slave structure in which the
master controls the interface access to the sensor. The option of using the
intelligence that is integrated into the sensor provides you with new methods
to commission your device. Benefits of IO-Link technology range from
reduced installation time during startup to increased diagnostics over the
lifetime of the machine. Other benefits of IO-Link technology include:
• Reduced inventory and operating costs
• Increased uptime/productivity
• Simplified design, installation, creation, and maintenance
• Enhanced flexibility and scalability
• Detailed diagnostic information for preventive maintenance
Why IO-Link? IO-Link offers a full range of advanced features and functions
Seamless Integration
• Forward and backward compatible
• No special cables required
• Connectivity options remain the same
• Access IO-Link functionality by simply connecting an IO-Link enabled
device to an IO-Link master
IMPORTANT This chapter provides a short overview of IO-Link technology. For more
details, see the IO-Link specification at io-link.com.

14 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 2 IO-Link Overview
Real-time Diagnostics and Trending
• Real-time monitoring of the entire machine down to the IO-Link device
level
• Optimized preventative maintenance-identify and correct issues before
Anomaly can occur
• Detect IO-Link device malfunctions/Anomalies
IO-Link Device Status
• Real-time monitoring verifies that IO-Link devices are operating
correctly
• Detect damaged IO-Link device and pinpoint their exact location for
quick troubleshooting through Application-Specific Name parameter
Device Profiles and Automatic Device Configuration
• Device configurations are stored in the IO-Link master module
• Multiple configurations can be stored in controller to support changes in
machine production, for example tool changes
• Within minutes instead of hours, modify sensor parameters to produce
different finished goods
Descriptive Tags
• Faster programming during initial setup
• More efficient troubleshooting process-data tags are named based on the
information they provide
• Easily monitor device data though intuitive tag names
How IO-Link Works? IO-Link delivers data over the same standard field cabling used today. By
connecting an IO-Link device to an IO-Link master, the field-device data and
diagnostics are accessible. So, go beyond detecting products on the machine-
now the health of the machine can be monitored as it runs.
Figure 5 - Typical IO-Link Wiring
Pin Signal Remark
1L+ 24V
2 Out Depends on sensor
3L- Ground
4C/Q
Communication/
switching signal
IMPORTANT It is possible that the response time of an IO-Link system is not fast
enough for high-speed applications.

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 15
Chapter 2 IO-Link Overview
Transmission Rates
Three communication rates are specified for the IO-Link device:
•COM1=4.8kBd
• COM2 = 38.4 kBd
• COM3 = 230.4 kBd
An IO-Link device typically supports only one of the specified transmissions
rates (see IO-Link Specifications on page 53). IO-Link V1.1 specification
requires an IO-Link master to support all three communication rates.
Transmission Quality
The IO-Link communication system operates at a 24V level. If a transmission
fails, the frame is repeated two more times. If the transmission fails on the
second try, the IO-Link master recognizes a communication failure and
signals it to the controller.
Response Time of the IO-Link System
The device description file (IODD) of the device contains a value for the
minimum cycle time of the device. This value indicates the time intervals at
which the master addresses the device. The value has a large influence on the
response time. In addition, the master has an internal processing time that is
included in the calculation of the system response time.
Devices with different minimum cycle times can be configured on one master.
The response time differs so for these devices. When configuring the master,
you can specify a fixed cycle time (minimum of 3 ms) and the device-specific
minimum cycle time that is stored in the IODD. The master then addresses the
device that is based on this specification. The typical response time for a device
therefore results from the effective cycle time of the device and the typical
internal processing time of the master.
IO-Link Data Types There are four data types available through IO-Link:
Process Data
The process data of the devices are transmitted cyclically in a data frame in
which the device specifies the size of the process data. Depending on the
device, 0...32 bytes of process data are possible (for each input and output). The
consistency width of the transmission is not fixed and is thus dependent on
the master.
Process data →Cyclic data
Value status →Cyclic data
Device data →Acyclic data
Events →Acyclic data

16 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 2 IO-Link Overview
Value Status
The value status indicates whether the process data is valid or invalid. The
value status can be transmitted cyclically with the process data.
Device Data
Device data supports device-specific configurable parameters, identification
data, and diagnostic information. They are exchanged acyclically and at the
request of the IO-Link master. Device data can be written to the device (Write)
and read from the device (Read).
Events
When an event occurs, the device signals the presence of the event to the
master. The master then reads out the event. Events can be error messages and
warnings/maintenance data. Error messages are transmitted from the device
to the controller via the IO-Link master. The transmission of device
parameters or events occurs independently from the cyclic transmission of
process data.
Access IO-Link Data Cyclic Data
To exchange the cyclic process data between an IO-Link device and a
controller, the IO-Link data from the IO-Link master is placed on the address
ranges assigned beforehand. The user program on the controller accesses
the process values using these addresses and processes them. The cyclic data
exchange from the controller to the IO-Link device is performed in reverse.
Acyclic Data
Acyclic data, such as device parameters or events, are exchanged using a
specified index range. The controller accesses these using Explicit Messaging.
The use of the index and subindex ranges allows targeted access.
I/O System Startup If the port of the master is set to IO-Link mode, the IO-Link master attempts to
communicate with the connected IO-Link device. To do so, the IO-Link master
sends a defined signal (wake up pulse) and waits for the IO-Link device to
reply.
The IO-Link master initially attempts to communicate at the highest defined
data transmission rate. If unsuccessful, the IO-Link master then attempts to
communicate at the next lower data transmission rate.
If the master receives a reply, the communication begins. Next, it exchanges
the communication parameters. If necessary, parameters that are saved in the
system are transmitted to the device. Then, the cyclic exchange of the process
data and value status begins.

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 17
Chapter 2 IO-Link Overview
Assign Device Parameters A device that is built for a specific application requires changes to parameter
settings. The device parameters and setting values are contained in the IODD
of the device.
I/O Device Description (IODD) files contain information about the device
identity, parameters, process data, diagnostic data, and communication
properties. These files are required to establish communication with the
sensors via IO-Link.
The IODD consists of multiple data files; the main file and several optional
language files are in XML-format and graphic files are in PNG format
(portable network graphics). These files adhere to the IO-Link open standard,
which means that they can be used with any IO-Link masters.
IODD files are assigned using Studio 5000® and the 1734-4IOL Add-on Profile
(AOP). (a)
(a) When using the 1734-4IOL IO-Link master module.

18 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 2 IO-Link Overview
Notes:

Rockwell Automation Publication 856T-UM001B-EN-P - April 2021 19
Chapter 3
Configure the 856T-B24LC IO-Link Module
This chapter describes the physical hardware and software that is required to
configure the 856T-B24LC module. It also provides a guide to hardware
installation.
Products Required Hardware
• 856T-B24LC IO-Link module
• CompactLogix™ or ControlLogix® PLC Platform
• POINT I/O™ Communications Interface: 1734-AENTR
• POINT I/O IO-Link Master Module: 1734-4IOL
• POINT I/O terminal base: 1734-TB
• RJ45 network cable for EtherNet/IP™ connectivity: 1585J-M8TBJM-1M9*
• 889D cordsets (optional): 889D-F5AC-5** (IO-Link maximum cable
length is 20 m [65.6 ft])
Software
• Studio 5000® environments, version 20 and higher
• Sensor-specific I/O Device Description (IODD)
• 1734-4IOL IO-Link Add-on Profile (AOP)
Figure 6 shows a POINT I/O chassis with a 1734-AENTR adapter and a
1734-4IOL IO-Link master module in the first slot. The 1734-AENTR adapter is
communicating with a CompactLogix controller via EtherNet/IP.
Figure 6 - IO-Link Hardware and Software Required
CompactLogix
Controller
Computer with
Studio 5000
1606 Auxiliary
Power
1734 IO-Link
Master
889D Cordset
856T Control Tower™
Stack Light with
IO-Link Module
(856T-B24LC)

20 Rockwell Automation Publication 856T-UM001B-EN-P - April 2021
Chapter 3 Configure the 856T-B24LC IO-Link Module
AOP Installation Add-on Profiles are files that you add to your Rockwell Automation library.
These files contain the pertinent information for configuring a device that is
added to the Rockwell Automation network. The Add-on Profile simplifies the
setup of devices because it presents the necessary fields in an organized
fashion. The Add-on Profile allows for the efficient configuration of systems.
The Add-on Profile is a folder that contains numerous files for the device. It
comes as an installation package.
Before you start making a project in Studio 5000, verify that the proper and
latest versions of the AOP files are installed. In this example, you need the AOP
for 1734-AENTR (POINT I/O) and 1734-4IOL (IO-Link Master).
If the AOP is required to be downloaded and installed, you can find it at:
download.rockwellautomation.com/esd/
download.aspx?downloadid=addonprofiles
Extract the AOP zip file, open the folder, and click the MPSetup.exe file.
Create Project The following steps show how to create simple configuration with 856T-B24LC
module.
To begin a new project in Studio 5000, follow these steps.
1. Click the Studio 5000 icon. In this example, version 32 of Studio 5000 is
used.
2. Click New Project