Allen-Bradley

Allen-Bradley 1785-L40B PLC-5/40 Controller Processor

SKU 1785-L40B

In stock
  • 12-month warranty
  • Free returns within 30 days
  • Manufacturer: Allen-Bradley

  • Product No.: 1785-L40B

  • Country of origin:United States

  • Product Type: PLC Controller Processor

  • Payment: T/T, Western Union

  • Weight: 950g

  • Dimensions: 25.4 x 15.2 x 5.1 cm

  • Shipping port: Xiamen

  • Warranty: 12 months

Description

The Allen-Bradley 1785-L40B is a high-performance PLC-5/40 programmable controller processor designed to execute complex control algorithms and manage extensive I/O architectures within the PLC-5 chassis environment. This processor is engineered for medium-to-large-scale industrial automation applications requiring robust processing power, deterministic scan times, and versatile communication routing across legacy network infrastructures.

The controller mounts directly into a standard PLC-5 backplane slot and integrates battery-backed static RAM for user program storage, supplemented by an EEPROM program backup option. It features embedded DH+ and Universal Remote I/O interfaces, allowing seamless data exchange, multi-rack expansion up to 61 total I/O chassis, and multi-tier network integration for distributed factory floor automation.

Features

    Supports up to 2,048 total digital inputs and 2,048 digital outputs, or a complementary mix
    Accommodates up to 2,048 maximum analog I/O points
    Equipped with 4 built-in Data Highway Plus (DH+) and Universal Remote I/O communication ports
    Configurable RS-232, RS-423, and RS-422A serial communication channel for point-to-point interface
    Backplane current draw of 3.3A at 5VDC with a total power dissipation of 17.3W
    Operating temperature range of -40 to 85 Celsius (-40 to 185 Fahrenheit)

Applications

    Large-scale discrete manufacturing and sequential logic control loops
    Distributed rack system management via Universal Remote I/O links
    Legacy Data Highway Plus (DH+) network supervisory communication
    Process control and analog data acquisition in continuous industrial plants

Technical Specifications

Parameter Specification
Manufacturer Allen-Bradley / Rockwell Automation
Product Type PLC-5 Controller Processor
Catalog Number 1785-L40B
Series PLC-5 / PLC-5/40
Memory Type Battery-backed static RAM
Maximum Digital I/O Capacity 2,048 inputs / 2,048 outputs
Maximum Analog I/O Capacity 2,048 analog I/O
Communication Ports 4 DH+ / Remote I/O channels, 1 configurable serial port (RS-232/423/422A)
Backplane Current Load 3.3A at 5VDC
Power Dissipation 17.3W
Operating Temperature -40 to 85 Celsius (-40 to 185 Fahrenheit)
Country of Origin United States

Compliance and Certifications

    UL Listed Industrial Control Equipment
    CE compliant for applicable directives
    C-Tick mark certified

FAQ

What is the maximum I/O capacity of the Allen-Bradley 1785-L40B?

The 1785-L40B supports up to 2,048 digital inputs and 2,048 digital outputs (or a complementary mix), along with up to 2,048 maximum analog I/O points across the control system.

What communication ports are built into the 1785-L40B processor?

The controller includes four DH+ / Universal Remote I/O channels that can function as adapters or scanners, plus one serial communication channel configurable for RS-232, RS-423, and RS-422A standards.

How is user memory retained on the PLC-5/40 processor?

User memory is stored on battery-backed static RAM, with an optional EEPROM module available for program backup and non-volatile storage.

What chassis power is required for this controller?

The 1785-L40B draws 3.3A of backplane current from the 5VDC power supply and generates a total power dissipation of 17.3W.

View all FAQs →

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  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our technical warranty.
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Global Express Shipping

  • Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
  • Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
  • Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

  • 30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
  • 12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).


For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .

TECHNICAL SPECIFICATIONS

Country of origin
United States

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