How-To Guide  ·  Allen-Bradley CompactLogix 5370  ·  Controller Setup & Programming

1769-L27ERM-QBFC1B: Installation, Studio 5000 Configuration, and First Program Guide

CompactLogix 5370 L2 · 1 MB Memory · Dual EtherNet/IP · Studio 5000 Logix Designer

1. Controller Overview

The 1769-L27ERM-QBFC1B is a packaged programmable automation controller in the CompactLogix 5370 family. The fixed configuration integrates the controller, AC power supply, and 1769 expansion bus into one unit. It is designed for standalone machine control and small distributed systems requiring dual-port EtherNet/IP connectivity and local 1769 Compact I/O expansion. The controller is programmed with Studio 5000 Logix Designer and supports Relay Ladder Logic, Structured Text, Function Block Diagram, and Sequential Function Chart languages.

Catalog Number Breakdown

Key Specifications

2. Hardware Installation

The 1769-L27ERM-QBFC1B is a packaged controller with a built-in AC power supply. Local 1769 Compact I/O modules mount directly to the right side and connect via the 1769 tongue-and-groove expansion bus.

System Assembly

The 1769-L27ERM supports up to 4 local 1769 I/O modules connected directly to the right side of the controller. A right end cap (1769-ECR) must be installed on the last module to terminate the expansion bus.

Installation Steps

1. Mount the controller on a 35 mm DIN rail or panel-mount using two screws. Allow adequate clearance above and below for ventilation and wiring.
2. Connect each 1769 I/O module to the right side of the controller by aligning the tongue-and-groove bus connector and sliding the module until it locks into place.
3. Install the 1769-ECR right end cap on the last I/O module to terminate the expansion bus. The end cap is mandatory — do not omit it.
4. Wire AC power to the controller's AC power terminals (L1, L2/N, PE). The embedded power supply accepts 100…240V AC, 47…63 Hz. Connect protective earth (PE) ground to the PE terminal.
5. Connect the EtherNet/IP cable(s) to one or both of the dual Ethernet ports on the front of the controller.
6. Install the 1784-SD1 SD card (sold separately) if program backup and restore is desired. The SD card slot is located on the front of the controller.
7. Wire field I/O devices (sensors, actuators) to the 1769 I/O module terminals per the module's wiring diagram.

3. Studio 5000 Project Setup

After installing the controller, create a Studio 5000 Logix Designer project to program and configure it.

Creating a New Project

1. Open Studio 5000 Logix Designer.
2. Select File → New Project.
3. In the Controller list, expand CompactLogix 5370 and select 1769-L27ERM.
4. Enter a Name for the controller (e.g., MachineLine1).
5. Click OK. The project opens with the controller in the I/O Configuration tree.

Adding Local I/O Modules

1. In the Controller Organizer, expand I/O Configuration → expand the CompactBus node (represents the local 1769 expansion bus).
2. Right-click the CompactBus node → New Module.
3. Search for the I/O module catalog number (e.g., 1769-IQ16 for a 16-point 24V DC input module), select it, and click Create.
4. Set the Name and Slot number. Slot 0 is the first module position to the right of the controller.
5. Click OK. Repeat for each local I/O module in the system.

4. EtherNet/IP Network Configuration

The 1769-L27ERM has two embedded EtherNet/IP ports that support star, linear, and Device Level Ring (DLR) topologies. Both ports share a single IP address. For DLR, connect one port to each segment of the ring.

Setting the Controller IP Address

1. Connect an Ethernet cable from one of the controller's dual Ethernet ports to your network switch or directly to your PC.
2. Use the BOOTP/DHCP Server utility (included with Studio 5000) to assign a static IP address to the controller's MAC address.
3. Alternatively, browse to the controller in RSLinx Classic via the EtherNet/IP driver and right-click to set the IP address.
4. To assign the IP within Studio 5000, open the controller properties → General tab and enter the desired IP address, subnet mask, and gateway.
5. For DLR ring topology, connect Port 1 to one node in the ring and Port 2 to the adjacent node. One device in the ring must be configured as the Ring Supervisor.

Adding Remote I/O Adapters

1. In the I/O Configuration, right-click the Ethernet port node → New Module.
2. Search for the remote adapter catalog number: 1734-AENT for POINT I/O, 5069-AENTR for Compact 5000 remote I/O, or 1769-AENTR for 1769 remote I/O.
3. Set the IP Address, Name, and connection parameters to match the physical adapter.
4. Right-click the adapter node → New Module to add remote I/O modules under the adapter. Repeat for each remote node.

5. Download & Go Online

After configuring the project, download it to the controller and go online to monitor execution.

Download Steps

1. Set the controller keyswitch to REM (Remote) position.
2. In Studio 5000, select Communications → Who Active (or click the communications path dropdown).
3. Browse the network tree and select your 1769-L27ERM controller.
4. Click Download. Studio 5000 transfers the project to the controller.
5. When prompted, choose to go to Run Mode or Remote Program Mode.
6. To go online without downloading, select Communications → Go Online.

Controller Operation Modes

6. Troubleshooting

The 1769-L27ERM-QBFC1B has several LED indicators on the front panel for diagnosing controller and network status. Refer to 1769-UM021 for the complete fault code listing.

LED Indicators

Common Issues

7. Related CompactLogix 5370 Controllers

8. Related Guides

Reference Documentation

The following Rockwell Automation publications were used as references for this guide.