Rockwell Automation Allen-Bradley MicroLogix 1400 User manual

User Manual Original Instructions
MicroLogix 1400
Programmable Controllers
Bulletins 1766 Controllers and 1762 Expansion I/O

2Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
MicroLogix 1400 Programmable Controllers 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.
These labels may also be on or inside the equipment to provide specific precautions.
The following icon may appear in the text of this document.
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).
Identifies information that is useful and can help to make a process easier to do or easier to understand.

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 3
Table of Contents
Preface
About This Publication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Purpose of this Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Download Firmware, AOP, EDS, and Other Files . . . . . . . . . . . . . . . . . . . 11
Summary of Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Additional Resources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Chapter 1
Hardware Overview Hardware Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Component Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
MicroLogix 1400 Memory Module and Built-in Real-Time Clock. . 14
1762 Expansion I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Communication Cables. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Firmware Revision History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Communication Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Chapter 2
Install Your Controller Installation Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Safety Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Hazardous Location Considerations. . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Disconnect Main Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Safety Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Periodic Tests of Master Control Relay Circuit. . . . . . . . . . . . . . . . . . 21
Power Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Isolation Transformers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Power Supply Inrush. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Loss of Power Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Input States on Power Down . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Other Types of Line Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Prevent Excessive Heat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Master Control Relay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Emergency-Stop Switches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Install a Memory Module . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Use the Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Connect the Battery Wire Connector . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Controller Mounting Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Controller and Expansion I/O Spacing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Mount the Controller. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
DIN Rail Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Panel Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
1762 Expansion I/O Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Mount 1762 Expansion I/O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
DIN Rail Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Panel Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Table of Contents
Connect Expansion I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Chapter 3
Wire Your Controller Wiring Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Wiring Recommendation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Wire without Spade Lugs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Wire with Spade Lugs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Use Surge Suppressors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Recommended Surge Suppressors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Ground the Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Wiring Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Terminal Block Layouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Sinking and Sourcing Wiring Diagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . 40
1766-L32BWA, 1766-L32AWA, 1766-L32BXB, 1766-L32BWAA, 1766-
L32AWAA, 1766-L32BXBA Wiring Diagrams . . . . . . . . . . . . . . . . . . . . 40
Controller I/O Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Minimize Electrical Noise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Wire Your Analog Channels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Analog Channel Wiring Guidelines. . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Minimize Electrical Noise on Analog Channels . . . . . . . . . . . . . . . . . 44
Ground Your Analog Cable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Expansion I/O Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Digital Wiring Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Analog Wiring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Chapter 4
Communication Connections Supported Communication Protocols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Default Communication Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Use the Communications Toggle Functionality . . . . . . . . . . . . . . . . . . . . 58
Change Communication Configuration . . . . . . . . . . . . . . . . . . . . . . . 59
Connect to the RS-232 Port. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Make a DF1 Point-to-Point Connection . . . . . . . . . . . . . . . . . . . . . . . . 61
Modem . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Connect to a DF1 Half-Duplex Network . . . . . . . . . . . . . . . . . . . . . . . . 63
Connect to a RS-485 Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
DH-485 Configuration Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Recommended Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
DH-485 Communication Cable. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Connect the Communication Cable to the DH-485 Connector. . . . 67
Ground and Terminate the DH-485 Network . . . . . . . . . . . . . . . . . . . 68
Connect the AIC+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Cable Selection Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Recommended User-Supplied Components . . . . . . . . . . . . . . . . . . . . 71
Install and Attach the AIC+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Power the AIC+. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Connect to Ethernet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Ethernet Connections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74

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Table of Contents
Chapter 5
LCD and Keypad Operating Principles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Startup Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Main Menu and Default Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
Operating Buttons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Select Between Menu Items . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Cursor Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Set Values. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
I/O Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
View I/O Status. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Monitor User Defined Target Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Target User Defined File Number (TUF) . . . . . . . . . . . . . . . . . . . . . . . 82
Monitor a Bit File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Monitor Integer Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Monitor Double Integer files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Monitor Floating Point Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Monitor System Status Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Mode Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Controller Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
Change Mode Switch Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
User-defined LCD Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
User-defined LCD Screen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Configure Advanced Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Change Key In Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Key In Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Change Key In Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Communications Toggle Functionality. . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Ethernet Network Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
View Ethernet Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Configure the IP Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Configure the Ethernet Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Configure Ethernet Protocol Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Trim Pots . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Trim Pot Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Change Data Value of a Trim Pot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Trim Pot Configuration in LCD Function File . . . . . . . . . . . . . . . . . 109
Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
View System Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
View Fault Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Save or Load Communication EEPROM. . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Save Communication EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 111
Load communication EEPROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
LCD setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Configure Contrast Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Configure the Back Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Protocol Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Modbus RTU Slave Node Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
LCD Password Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Set the LCD Password. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117

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Table of Contents
Activate the LCD Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Deactivate the LCD Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Change LCD Password . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Chapter 6
Real-Time Clock and Memory
Modules
Real-Time Clock Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Operation at Power-up and Entering a Run or Test Mode. . . . . . . 123
Write Data to the Real-Time Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
RTC Battery Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Memory Module Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
User Program, User Data, Datalog, and Recipe Back-up . . . . . . . . 124
Program Compare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Data File Download Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Memory Module Write Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Removal/Insertion Under Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Memory Module Information File . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Program /Data Download . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Program /Data Upload . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Chapter 7
Online Editing Overview of Online Editing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Online Editing Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Effects of Online Editing On Your System . . . . . . . . . . . . . . . . . . . . . . . . 128
System Impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Data Table File Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Online Edit Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
Directions and Cautions for MicroLogix 1400 Online Editing User. . 129
A Download is Required Before Starting Online Editing. . . . . . . . 129
Types of Online Editing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Edit Functions in Runtime Online Editing . . . . . . . . . . . . . . . . . . . . 130
Edit Functions in Program Online Editing . . . . . . . . . . . . . . . . . . . . 130
Chapter 8
Auto Reset Functionality Automatic Controller Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Enable the Status Bit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Appendix A
Specifications Expansion I/O Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Analog Modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
Appendix B
Replacement Parts MicroLogix 1400 Replacement Kits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Lithium Battery (1747-BA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
Battery Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 7
Table of Contents
Disposal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
Appendix C
Troubleshoot Your System Understand the Controller Status Indicators . . . . . . . . . . . . . . . . . . . . . 153
Controller Status Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
Status Indicators on the LCD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
I/O Status Indicators on the LCD. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
Normal Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Controller Error Recovery Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Analog Expansion I/O Diagnostics and Troubleshooting. . . . . . . . . . . 156
Module Operation and Channel Operation . . . . . . . . . . . . . . . . . . . . 156
Power-up Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Critical and Non-Critical Errors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Module Error Definition Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Error Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Contact Rockwell Automation for Assistance . . . . . . . . . . . . . . . . . . . . . 159
Appendix D
Use ControlFLASH to Upgrade
Your Operating System
Prepare for Firmware Update . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Install ControlFLASH Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Use DMK Extraction Tool for Firmware Update . . . . . . . . . . . . . . . 161
Prepare the Controller for Firmware Update . . . . . . . . . . . . . . . . . . 163
Use ControlFLASH for Firmware Update . . . . . . . . . . . . . . . . . . . . . . . . . 164
ControlFLASH Error Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Missing or Corrupt OS state. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172
Recover from Missing or Corrupt OS State . . . . . . . . . . . . . . . . . . . . 173
Appendix E
Connect to Networks via RS-232/
RS-485 Interface
RS-232 Communication Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
RS-485 Communication Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
DF1 Full-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
DF1 Half-Duplex Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
DF1 Half-Duplex Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Considerations When Communicating as a DF1 Slave on a Multi-
drop Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 177
Using Modems with MicroLogix Programmable Controllers . . . . 178
DH-485 Communication Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
DH-485 Configuration Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
Devices that use the DH-485 Network. . . . . . . . . . . . . . . . . . . . . . . . . 179
Important DH-485 Network Planning Considerations. . . . . . . . . . 180
Example DH-485 Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Modbus Communication Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
ASCII . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Distributed Network Protocol (DNP3) . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Disable Serial Channels 0 and 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185

8Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Table of Contents
Appendix F
MicroLogix 1400 Distributed
Network Protocol
Channel Configuration for DNP3 Slave. . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Channel 0 and Channel 2 Link Layer Configuration . . . . . . . . . . . . 188
Channel 1 Link Layer Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . 189
DNP3 Slave Application Layer Configuration . . . . . . . . . . . . . . . . . . 190
Channel 0 and Channel 2 Link Layer Configuration Parameters. 191
Channel 1 (Ethernet) Link Layer Configuration Parameters. . . . . 194
DNP3 Slave Application Layer Configuration Parameters. . . . . . . 198
DNP3 Slave Application Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Function Codes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Internal Indications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
DNP3 Objects and Controller Data Files . . . . . . . . . . . . . . . . . . . . . . . . . . 213
DNP3 Data Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
DNP3 Configuration Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 216
DNP3 Binary Input Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
DNP3 Binary Output Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
DNP3 Double Bit Binary Input Object . . . . . . . . . . . . . . . . . . . . . . . . 223
DNP3 Counter Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
DNP3 Frozen Counter Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
DNP3 Analog Input Object. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229
DNP3 Analog Output Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 232
DNP3 BCD Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 233
DNP3 Data-Set Object. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Object Quality Flags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
DNP3 Device Attribute Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Event Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
Generate Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 247
DNP3 10K Event Logging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Control Generating Event . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
Report Event By Polled Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Report Event By Unsolicited Response. . . . . . . . . . . . . . . . . . . . . . . . 252
Collision Avoidance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Time Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Download a User Program via DNP3 Network . . . . . . . . . . . . . . . . . . . . 255
Default Directories and Files. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
Generating *.IMG files using RSLogix 500/RSLogix Micro. . . . . . 256
Rules for File Authentication. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 258
Rules for Downloading a User Program. . . . . . . . . . . . . . . . . . . . . . . 258
Rules for Uploading a User Program. . . . . . . . . . . . . . . . . . . . . . . . . . 259
Rules for Initializing a User Program . . . . . . . . . . . . . . . . . . . . . . . . . 260
Rules for uploading Communication Status Files . . . . . . . . . . . . . . 260
Start and Stop User Programs (Mode Change) via DNP3 Network
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Initialize User Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Start User Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Stop User Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 261
Diagnostics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Diagnostics for Ethernet Channel (Channel 1) . . . . . . . . . . . . . . . . . 266
Diagnostics for Secure Authentication. . . . . . . . . . . . . . . . . . . . . . . . 270

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 9
Table of Contents
Function Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Implementation Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 273
Appendix G
Connect to Networks via
Ethernet Interface
MicroLogix 1400 Controllers and Ethernet Communication. . . . . . . . 281
MicroLogix 1400 Performance Considerations . . . . . . . . . . . . . . . . . . . . 282
MicroLogix 1400 and PC Connections to the
Ethernet Network. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Connecting an Ethernet switch on the Ethernet Network. . . . . . . 283
Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Ethernet Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Duplicate IP Address Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Configure the Ethernet Channel on the MicroLogix 1400 . . . . . . . . . . 286
Configure Using RSLogix 500/RSLogix Micro Programming Software
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Configure Using BOOTP. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Using the Rockwell Automation BOOTP/DHCP Utility . . . . . . . . . 288
Use a DHCP Server To Configure Your Processor . . . . . . . . . . . . . . . . . 290
Subnet Masks and Gateways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
Manually Configure Channel 1 for Controllers on Subnets . . . . . . 291
MicroLogix 1400 Embedded Web Server Capability . . . . . . . . . . . . . . . 291
Disable the Ethernet Channel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 292
Appendix H
System Loading and Heat
Dissipation
System Loading Calculations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293
System Loading Example Calculations . . . . . . . . . . . . . . . . . . . . . . . 293
System Loading Worksheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
Current Loading. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
Calculating Heat Dissipation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303

10 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Table of Contents
Notes:

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 11
Preface
About This Publication Use this manual if you are responsible for designing, installing, programming,
or troubleshooting control systems that use MicroLogix™ 1400 controllers.
You should have a basic understanding of electrical circuitry and familiarity
with relay logic. If you do not, obtain the proper training before using this
product.
Rockwell Automation recognizes that some of the terms that are currently
used in our industry and in this publication are not in alignment with the
movement toward inclusive language in technology. We are proactively
collaborating with industry peers to find alternatives to such terms and
making changes to our products and content. Please excuse the use of such
terms in our content while we implement these changes.
Purpose of this Manual This manual is a reference guide for MicroLogix 1400 controllers and
expansion I/O. It describes the procedures you use to install, wire, and
troubleshoot your controller. This manual:
• explains how to install and wire your controllers
• gives you an overview of the MicroLogix 1400 controller system
See publication 1766-RM001, MicroLogix 1400 Programmable Controllers
Instruction Set Reference Manual for the MicroLogix 1400 instruction set and
for application examples to show the instruction set in use. See your
RSLogix 500®/RSLogix™ Micro programming software user documentation
for more information on programming your MicroLogix 1400 controller.
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.
Summary of Changes This publication contains the following new or updated information. This list
includes substantive updates only and is not intended to reflect all changes.
Additional Resources These documents contain additional information concerning related products
from Rockwell Automation.
Topic Page
Updated template throughout
Added inclusive language acknowledgment 11
Added Auto Reset Feature 131
Resource Description
MicroLogix 1400 Programmable Controllers Instruction Set Reference Manual
1766-RM001 Information on the MicroLogix 1400 Controllers instruction set.
MicroLogix 1400 Programmable Controllers Installation Instructions 1766 -IN001 Information on mounting and wiring the MicroLogix 1400 Controllers, including a mounting
template for easy installation.
Advanced Interface Converter (AIC+) User Manual 1761-UM004 A description on how to install and connect an AIC+. This manual also contains information on
network wiring.
DeviceNet Interface User Manual 1761-UM005 Information on how to install, configure, and commission a DeviceNet® Interface.

12 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Preface
You can view or download publications at rok.auto/literature.
DF1 Protocol and Command Set Reference Manual 1770-6.5.16 Information on DF1 open protocol.
Modbus Protocol Specifications available from www.modbus.org Information about the Modbus protocol.
Distributed Network Protocol (DNP3) Specifications Available from www.dnp.org Information about the Distributed Network Protocol.
System Security Design Guidelines Reference Manual, SECURE-RM001 Provides guidance on how to conduct security assessments, implement Rockwell Automation® products in a secure system, harden the control system, manage user access, and dispose of
equipment.
UL Standards Listing for Industrial Control Products, publication CMPNTS-SR002 Assists original equipment manufacturers (OEMs) with construction of panels, to help ensure that
they conform to the requirements of Underwriters Laboratories.
American Standards, Configurations, and Ratings: Introduction to
Motor Circuit Design, publication IC-AT001 Provides an overview of American motor circuit design based on methods that are outlined in the
NEC.
Industrial Components Preventive Maintenance, Enclosures, and Contact Ratings
Specifications, publication IC-TD002 Provides a quick reference tool for Allen-Bradley® industrial automation controls and
assemblies.
Safety Guidelines for the Application, Installation, and Maintenance of Solid-state
Control, publication SGI-1.1
Designed to harmonize with NEMA Standards Publication No. ICS 1.1-1987 and provides general
guidelines for the application, installation, and maintenance of solid-state control in the form of
individual devices or packaged assemblies incorporating solid-state components.
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.
Resource Description

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 13
Chapter 1
Hardware Overview
Hardware Features The MicroLogix 1400 programmable controller contains a power supply, input
and output circuits, a processor, an isolated combination RS-232/RS-485
communication port, an Ethernet port, and a non-isolated RS-232
communication port. Each controller supports 32 discrete I/O points (20
digital inputs, 12 discrete outputs) and 6 analog I/O points (4 analog inputs and
2 analog outputs: 1766-L32BWAA, 1766-L32AWAA, and 1766-L32BXBA only).
The hardware features of the controller are shown below.
Topic Page
Hardware Features 13
Component Descriptions 14
Communication Cables 15
Programming 16
Communication Options 17
1
ESC
OK
256 7
89101113 12
43
1
Left side view Top view
Controller Description
Description Description
1 Comm port 2 – 9-pin D-Shell RS-232C connector 8 Battery connector
2Memory module(1) 9Outputterminalblock
3 User 24V (for 1766-BWA and 1766-BWAA only) 10 LCD Display
4 Input terminal block 11 Indicator LED panel
5 LCD Display Keypad (ESC, OK, Up, Down, Left, Right) 12 Comm port 1 – RJ45 connector
6 Battery compartment 13 Comm port 0 – 8-pin mini DIN RS-232C/RS-485 connector
7 1762 expansion bus connector
(1) See MicroLogix 1400 Memory Module Installation Instructions, publication 1766-IN010 for instructions on installing the memory module.

14 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Chapter 1 Hardware Overview
Component Descriptions MicroLogix 1400 Memory Module and Built-in Real-Time Clock
The controller has a built-in real-time clock to provide a reference for
applications that need time-based control.
The controller is shipped with a memory module port cover in place. You can
order a memory module, 1766-MM1, as an accessory. The memory module
provides optional backup of your user program and data, and is a means to
transport your programs between controllers.
The program and data in your MicroLogix 1400 is non-volatile and is stored
when the power is lost to the controller. The memory module provides
additional backup that can be stored separately. The memory module does not
increase the available memory of the controller.
Figure 1 - 1766-MM1 Memory Module
Controller Input and Output Description
Catalog Number
Description
Input
Power User Power Embedded Discrete I/O EmbeddedAnalog I/O Comm. Ports
1766-L32BWA
100/240V AC
24V DC 12 Fast 24V DC Inputs 8 Normal 24V DC Inputs
12 Relay Outputs
None
1 RS-232/RS-485(1)
1 Ethernet
1 RS-232(2)
1766-L32AWA
None
20 120V AC Inputs
12 Relay Outputs
1766-L32BXB 24V DC
12 Fast 24V DC Inputs
8 Normal 24V DC Inputs
6 Relay Outputs
3 Fast DC Outputs
3 Normal DC Outputs
1766-L32BWAA
100/240V AC
24V DC 12 Fast 24V DC Inputs 8 Normal 24V DC Inputs
12 Relay Outputs
4 Voltage Inputs
2 Voltage Outputs
1766-L32AWAA
None
20 120V AC Inputs
12 Relay Outputs
1766-L32BXBA 24V DC
12 Fast 24V DC Inputs
8 Normal 24V DC Inputs
6 Relay Outputs
3 Fast DC Outputs
3 Normal DC Outputs
(1) Isolated RS-232/RS-485 combo port.
(2) Non-isolated RS-232. Standard D-sub connector
Mod
ule
M
em
ory

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 15
Chapter 1 Hardware Overview
1762 Expansion I/O
1762 expansion I/O can be connected to the MicroLogix 1400 controller, as
shown below.
Figure 2 - 1762 Expansion I/O
Communication Cables Use only the following communication cables with the MicroLogix 1400
controllers. These cables are required for Class I Div. 2 applications.
• 1761-CBL-AM00 Series C or later
• 1761-CBL-AP00 Series C or later
• 1761-CBL-PM02 Series C or later
• 1761-CBL-HM02 Series C or later
A maximum of seven I/O modules, in any combination, can be connected to a
controller. See Appendix H to determine how much heat a certain combination
generates.
Expansion I/O
Catalog Number Description
Digital
1762-IA8 8-Point 120V AC Input Module
1762-IQ8 8-Point Sink/Source 24V DC Input Module
1762-IQ16 16-Point Sink/Source 24V DC Input Module
1762-IQ32T 32-Point Sink/Source 24V DC Input Module
1762-OA8 8-Point 120/240V AC Triac Output Module
1762-OB8 8-Point Sourcing 24V DC Output Module
1762-OB16 16-Point Sourcing 24V DC Output Module
1762-OB32T 32-Point Sourcing 24V DC Output Module
1762-OV32T 32-Point Sinking 24V DC Output Module
1762-OW8 8-Point AC/DC Relay Output Module
1762-OW16 16-Point AC/DC Relay Output Module
1762-OX6I 6-Point Isolated AC/DC Relay Output Module
1762-IQ8OW6 8-Point Sink/Source 24V DC Input and 6-Point AC/DC Relay Output Module
Analog
1762-IF4 4-Channel Voltage/Current Analog Input Module
1762-OF4 4-Channel Voltage/Current Analog Output Module
1762-IF2OF2 Combination 2-Channel Input 2-Channel Output Voltage/Current Analog Module
Temperature
1762-IR4 4-Channel RTD/Resistance Input Module
1762-IT4 4-Channel Thermocouple/mV Input Module
1762 Expansion I/O 1762 Expansion I/O Connected to MicroLogix 1400 Controller

16 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Chapter 1 Hardware Overview
• 1763-NC01 Series A or later
• 1747-CP3 Series A or later
Programming Programming the MicroLogix 1400 controller is done using RSLogix 500/
RSLogix Micro software, version 8.10.00 or later for Series A controllers and
version 8.30.00 or later for Series B and Series C controllers. Communication
cables for programming are available separately from the controller and
software.
Firmware Revision History
Features are added to the controllers through firmware upgrades. Use the
listing in Table 1 to be sure that your controller’s firmware is at the level you
need. Firmware upgrades are not required, except to allow you access to the
new features.
ATTENTION: UNSUPPORTED CONNECTION
Do not connect a MicroLogix 1400 controller to another MicroLogix family
controller such as MicroLogix 1000, MicroLogix 1200, MicroLogix 1500, or
the network port of a 1747-DPS1 Port Splitter using a 1761-CBL-AM00 (8-
pin mini-DIN to 8-pin mini-DIN) cable or equivalent.
This type of connection will cause damage to the RS-232/RS-485
communication port (Channel 0) of the MicroLogix 1400 and/or the
controller itself. The communication pins used for RS-485
communications on the MicroLogix 1400 are alternately used for 24V
power on the other MicroLogix controllers and the network port of the
1747-DPS1 Port Splitter.
Table 1 - MicroLogix 1400
Catalog Number OS(1)
Series
Letter
OS Revision
Letter
OS
Firmware
Release No. Release Date Enhancement
1766-L32AWA
1766-L32BWA
1766-L32BBB
A A FRN1 August 2005 Initial product release.
A B FRN2 October 2005 According to the SRAM component, MicroLogix 1400 may cause Hard-fault at the
start of the Operating System in the very high temperature environment. Corrected.
A C FRN3 February 2006 Added Data file write feature through web server.
1766-L32AWA
1766-L32BWA
1766-L32BBB BA FRN4 February2007
• Direct connection to RS-485 Network for DF1 half-duplex Master driver.
• Direct connection to RS-485 Network for DF1 half-duplex Slave driver.
• Direct connection to RS-485 Network for ASCII driver.
• Selectable Stop/Data Bits for Modbus Master RTU driver.
• Selectable Stop/Data Bits for Modbus Slave RTU driver.
• Selectable Stop/Data Bits for ASCII driver.
• Settable Inactivity Timeout feature for Ethernet driver.
• Unsolicited Ethernet messaging to RSLinx® OPC topic.
• CIP™ Generic messaging through the Ethernet port.
• Unconnected EtherNet/IP protocol for Ethernet driver.
• IP conflict detection mechanism.
• E-mail feature.
• Ethernet MSG break bit.
• DNS functionality when E-mail feature is used.
• Change IP Address using Ethernet MSG instruction.
• ST file type for all PCCC commands.
• HSC (High-Speed Counter) up to 40 K Hz.
• PTO/PWM up to 40 K Hz.
• 2-channel Analog Input Filter.
• Web View Disable for Data Files.
1766-L32AWA
1766-L32BWA
1766-L32BBB B B FRN5 May 2007
• Fixed defect for CIP Messaging Error when CIP service code is 4Bh or 4Ch.
• Fixed defect for the EtherNet/IP List Identity reply.
• Fixed defect for window size error in TCP/IP stack.
• Improved system interrupt delay time.

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 17
Chapter 1 Hardware Overview
Communication Options The MicroLogix 1400 controllers provide three communications ports, an
isolated combination RS-232/485 communication port (Channel 0), an
Ethernet port (Channel 1) and a non-isolated RS-232 communication port
(Channel 2).
The Channel 0 and Channel 2 ports on the MicroLogix 1400 can be connected
to the following:
• operator interfaces, personal computers, and so on, using DF1 Full
Duplex point-to-point
•aDH-485network
• a DF1 Radio Modem network
• a DF1 half-duplex network as an RTU Master or RTU Slave
• a Modbus network as an RTU Master or RTU Slave
• an ASCII network
• an Ethernet network using the Ethernet Interface module (catalog
number 1761-NET-ENI, or 1761-NET-ENIW)
• a DNP3 network as a Slave
When connecting to RS-485 network using DH-485, DF1 Half-Duplex Master/
Slave, Modbus RTU Master/Slave, or DNP3 Slave protocols, the MicroLogix
1400 can be connected directly via Channel 0 without an Advanced Interface
Converter, catalog number 1761-NET-AIC. The Channel 0 combo port provides
both RS-232 and RS-485 isolated connections. The appropriate electrical
interface is selected through your choice of communication cable. The existing
MicroLogix 1761 communication cables provide an interface to the RS-232
drivers. The 1763-NC01 cable provides an interface to the RS-485 drivers.
The controller may also be connected to serial devices, such as bar code
readers, weigh scales, serial printers, and other intelligent devices, using
ASCII. See Default Communication Configuration on page 58 for the
configuration settings for Channel 0. MicroLogix 1400 can be connected
directly to RS-485 network via channel 0, using ASCII.
The MicroLogix 1400 supports EtherNet/IP™ communication via the Ethernet
communication Channel 1. In addition, either Modbus TCP or DNP3 over IP
can be enabled for Channel 1. You can connect your controller to a local area
network that provides communication between various devices at 10 Mbps or
100 Mbps. This port supports CIP explicit messaging (message exchange) only.
The controller cannot be used for CIP implicit messaging (real-time I/O
messaging). The controller also includes an embedded web server which allows
viewing of not only module information, TCP/IP configuration, and diagnostic
information, but also includes the data table memory map and data table
monitor screen using a standard web browser.
See Chapter 4 for more information on connecting to the available
communication options.
1766-L32DWD B B FRN5 May 2007 • Initial Product release. Supports all the features listed above for the 1766-L32AWA,
1766-L32BWA, and 1766-L32BBB controllers.
(1) OS = Operating System.
Table 1 - MicroLogix 1400 (Continued)
Catalog Number OS(1)
Series
Letter
OS Revision
Letter
OS
Firmware
Release No. Release Date Enhancement

18 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Chapter 1 Hardware Overview
Notes:

Rockwell Automation Publication 1766-UM001O-EN-P - September 2021 19
Chapter 2
Install Your Controller
Installation Considerations Most applications require installation in an industrial enclosure (Pollution
Degree 2(a)) to reduce the effects of electrical interference (Over Voltage
Category II(b)) and environmental exposure. Locate your controller as far as
possible from power lines, load lines, and other sources of electrical noise such
as hard-contact switches, relays, and AC motor drives. For more information
on proper grounding guidelines, see Industrial Automation Wiring and
Grounding Guidelines publication 1770-4.1.
Topic Page
Installation Considerations 19
Safety Considerations 20
Power Considerations 21
Prevent Excessive Heat 22
Master Control Relay 23
Install a Memory Module 25
Use the Battery 26
Controller Mounting Dimensions 27
Controller and Expansion I/O Spacing 27
Mount the Controller 28
1762 Expansion I/O Dimensions 30
Mount 1762 Expansion I/O 30
Connect Expansion I/O 31
(a) Pollution Degree 2 is an environment where normally only non-conductive pollution occurs except that occasionally temporary
conductivity caused by condensation shall be expected.
(b) Overvoltage Category II is the load level section of the electrical distribution system. At this level, transient voltages are controlled and do
not exceed the impulse voltage capability of the products insulation.
ATTENTION: Electrostatic discharge can damage semiconductor devices inside
the controller. Do not touch the connector pins or other sensitive areas.
ATTENTION: Vertical mounting of the controller is not supported due to heat
build-up considerations.
ATTENTION: Be careful of metal chips when drilling mounting holes for your
controller or other equipment within the enclosure or panel. Drilled fragments that
fall into the controller or I/O modules could cause damage. Do not drill holes
above a mounted controller if the protective debris shields are removed or the
processor is installed.

20 Rockwell Automation Publication 1766-UM001O-EN-P - September 2021
Chapter 2 Install Your Controller
Safety Considerations Safety considerations are an important element of proper system installation.
Actively thinking about the safety of yourself and others, as well as the
condition of your equipment, is of primary importance. We recommend
reviewing the following safety considerations.
Hazardous Location Considerations
This equipment is suitable for use in Class I, Division 2, Groups A, B, C, D or
non-hazardous locations only. The following WARNING statement applies to
use in hazardous locations.
Use only the following communication cables in Class I, Division 2 hazardous
locations.
Disconnect Main Power
The main power disconnect switch should be located where operators and
maintenance personnel have quick and easy access to it. In addition to
WARNING: Do not place the MicroLogix 1400 Programmable Controller in direct
sunlight. Prolonged exposure to direct sunlight could degrade the LCD display and
have adverse effects on the controller.
The controller is not designed for outdoor use.
WARNING: EXPLOSION HAZARD
• Substitution of components may impair suitability for Class I, Division 2.
• Do not replace components or disconnect equipment unless power has been
switched off.
• Do not connect or disconnect components unless power has been switched off.
• This product must be installed in an enclosure. All cables connected to the product
must remain in the enclosure or be protected by conduit or other means.
• All wiring must comply with N.E.C. article 501-10(b) and/or in accordance with
Section 18-1J2 of the Canadian Electrical Code, and in accordance with the
authority having jurisdiction.
• For applicable equipment (for example, relay modules), exposure to some
chemicals may degrade the sealing properties of the materials used in these
devices:
- Relays, epoxy
It is recommended that you periodically inspect these devices for any
degradation of properties and replace the module if degradation is found.
Environment Classification Communication Cables
Class I, Division 2 Hazardous Environment
1761-CBL-AC00 Series C or later
1761-CBL-AM00 Series C or later
1761-CBL-AP00 Series C or later
1761-CBL-PM02 Series C or later
1761-CBL-HM02 Series C or later
2707-NC9 Series C or later
1763-NC01 Series A or later
1747-CP3 Series
WARNING: Explosion Hazard
Do not replace components, connect equipment, or disconnect equipment unless
power has been switched off.