Allen-Bradley 1769-L24ER-QBFC1B CompactLogix Controller Overview

The Allen-Bradley 1769-L24ER-QBFC1B belongs to the CompactLogix 5370 L2 family of programmable automation controllers. This packaged controller delivers the same CPU performance as L3 models but in a smaller form factor. It is ideal for hoisting, cranes, indexing tables, and packaging machines. The Allen-Bradley 1769-L24ER-QBFC1B combines logic, motion, and I/O processing in a single DIN-rail unit.

Key Technical Specifications

The Allen-Bradley 1769-L24ER-QBFC1B offers extensive built-in I/O and memory. Below are its core technical parameters.

• User Memory: 1 MB

• Non-Volatile Memory: 1 GB via included 1784-SD1 card (optional 2 GB 1784-SD2)

• Maximum Local Expansion: 4 x 1769 series modules

• Embedded Digital Inputs: 16 x 24V DC (sinking/sourcing)

• Embedded Digital Outputs: 16 x 24V DC (sinking)

• Digital Output Current per Point: 0.83 A at 40°C, 0.58 A at 55°C, 0.5 A at 60°C

• Digital Output Current per Module: 6.64 A at 40°C, 4.64 A at 55°C, 4 A at 60°C

• Analog Inputs: 4 x universal (differential or single-ended)

• Analog Input Signal Types: ±50mV, ±100mV, 0-5V, 1-5V, 0-10V, ±10V, 0-20mA, 4-20mA

• Analog Input Support: Thermocouple (K,S,R,B,J,T,E,N,C) and RTD (Platinum, Copper, Nickel)

• Analog Outputs: 2 x single-ended

• Analog Output Signal Types: 0-5V, 1-5V, 0-10V, ±10V, 0-20mA, 4-20mA

• High-Speed Counter (HSC) Inputs: 4 channels (250 kHz switching frequency)

• High-Speed Outputs: 4 channels (5-30V DC range)

• Communication Ports: 2 x Ethernet/IP, 1 x RS232, and 1 x USB

• Supported Protocols: ASCII, DH485, DF1, Ethernet/IP

• Ethernet Topologies: DLR supported with 256 EtherNet/IP and 120 TCP connections

• Axes over Ethernet: 2 axes for motion control

• Number of Tasks: 32 total tasks

• Programs per Task: Up to 100 programs

• Programming Languages: Relay Ladder, Structured Text, Function Block, and SFC

• Operating Temperature: -20°C to 60°C (-4°F to 140°F)

• Operating Voltage Range: 10-28.8V DC at 40°C, 10-27V DC at 55°C, 10-26.4V DC at 60°C

• Input Power: 24V DC nominal

• Current Draw (5V DC): 1 A

• Current Draw (24V DC): 0.8 A

• Continuous Isolation Voltage: 30V DC

• Anti-interference capability: High industrial immunity with open-type enclosure design.

• Mounting: DIN Rail

• Wire Size (Solid): 22 to 14 AWG

• Wire Size (Stranded): 22 to 16 AWG

• Wire Type: Copper, 90°C rating

• Replacement Terminal Block: 1769-RTBN18

Installation Guidelines

Follow these steps to install the Allen-Bradley 1769-L24ER-QBFC1B correctly.

1. Mount the controller on a standard 35 mm DIN rail in your cabinet.

2. Maintain 50 mm (2 inches) clearance from wireways and other components.

3. Proper clearance ensures adequate ventilation for reliable operation.

4. Snap the Allen-Bradley 1769-L24ER-QBFC1B firmly onto the rail.

5. Connect your 24V DC power supply to the embedded power terminals.

6. Wire your sensors, encoders, and actuators to the appropriate I/O channels.

7. Connect your programming device via USB, RS232, or Ethernet.

Use BOOTP-DHCP utility to assign an IP address using the controller’s MAC address. Do not remove the 1784-SD1 card in hazardous locations while power is applied. Use copper wires with 90°C minimum insulation rating.

Package Contents

Your package for the Allen-Bradley 1769-L24ER-QBFC1B includes the following items:

• Allen-Bradley 1769-L24ER-QBFC1B controller unit (1 unit)

• Pre-installed 1784-SD1 1GB Secure Digital memory card (1 unit)

• Anti-static protective packaging (1 unit)

Frequently Asked Questions FAQ

Q1: What is the difference between L24ER and L24ER-QBFC1B models?
A1: The Allen-Bradley 1769-L24ER-QBFC1B adds high-speed counter inputs, high-speed outputs, analog inputs, and analog outputs to the base model.

Q2: How many local expansion modules can this controller support?
A2: The Allen-Bradley 1769-L24ER-QBFC1B supports up to four 1769 series expansion modules.

Q3: Does this controller support motion control over Ethernet?
A3: Yes, the Allen-Bradley 1769-L24ER-QBFC1B supports up to two axes of motion control via Ethernet/IP.

Q4: What programming software is compatible with this controller?
A4: You can program the Allen-Bradley 1769-L24ER-QBFC1B using RSLogix 5000 or Studio 5000 software.

Q5: Can I use the HSC inputs for encoder feedback?
A5: Yes, the four high-speed counter inputs accept encoder signals at up to 250 kHz switching frequency.

Why Choose This Controller for Your Application?

You need a compact controller with built-in analog and high-speed capabilities. The Allen-Bradley 1769-L24ER-QBFC1B delivers 1MB of user memory with 16 DC I/O, 4 analog inputs, and 2 analog outputs. This controller handles four high-speed counter channels and four high-speed outputs for precise motion tasks. It supports DLR network topology for resilient communication with fault tolerance. The Allen-Bradley 1769-L24ER-QBFC1B works seamlessly with thermocouples and RTDs for temperature applications. Choose this model for small to medium control requirements without extra I/O modules. Its wide operating voltage range ensures stable performance in fluctuating power conditions.