Allen-Bradley 1785-L11B | PLC 5 Standard Processor

Overview

The 1785-L11B is a PLC 5 series standard processor from Allen-Bradley. It integrates I/O modules, operator interfaces, and remote devices to form a centralized control system.

This processor features 8K words of built-in memory and supports battery-backed static RAM for program retention. Additional EEPROM modules like 1785-ME16, -ME32, -ME64, or -M100 extend program backup capability.

The 1785-L11B communicates through a built-in Data Highway Plus (DH+) or Remote I/O port. DH+ allows remote programming, monitoring, and peer-to-peer communication between PLC-5 controllers.

Front panel indicators display the controller’s operational status. The BATT indicator signals battery health, PROC shows run/fault status, FORCE lights when I/O forces are active, and COMM indicates channel communication.

This processor supports up to 512 I/O points in any mix or 384 input + 384 output complementary configuration. It handles up to 5 local I/O chassis and 4 extended universal remote chassis, delivering robust control performance.

Technical Specifications

Features

• Integrates local, extended, and remote I/O modules seamlessly.

• Supports up to 512 I/O points for versatile industrial applications.

• Battery-backed RAM ensures data retention during power loss.

• Built-in DH+ port enables remote programming and peer-to-peer PLC communication.

• Front panel indicators provide clear real-time status monitoring.

• Optional EEPROM modules allow additional program backup security.

Installation Notes

• Mount the 1785-L11B in a standard PLC 5 chassis.

• Connect the DH+ or Remote I/O port according to network topology.

• Verify power supply and backplane connections before startup.

• Ensure proper ventilation to maintain operating temperatures and reliability.

FAQ

Q1: Is the 1785-L11B factory new and original?
A1: Yes, it is fully original, new, and in stock for immediate shipment.

Q2: What is the maximum I/O supported?
A2: Supports up to 512 total I/O points, including local, extended, and remote.

Q3: Does this processor have memory backup?
A3: Yes, it includes battery-backed static RAM and optional EEPROM modules for program retention.

Q4: Which communication ports are available?
A4: Features one RS-232/422/423 port and a built-in Data Highway Plus (DH+) port.

Q5: How fast is the I/O scan time?
A5: I/O scan ranges from 3 ms to 10 ms per rack depending on baud rate.