Skip to content
Free Ground Shipping | Overnight Shipping Available | Texas-based company, and all shipments come from the USA
(833) 800-7748

1785-LT Allen-Bradley

Original price $450.00 - Original price $500.00
Original price
$450.00
$450.00 - $500.00
Current price $450.00
Surplus - Tested (With Warranty)
Need a Specific Revision?
$450.00
2 in stock
New / Open-Box Surplus
Need a Specific Revision?
$500.00
3 in stock
Ships today if ordered by 1 PM CST
Overnight shipping available
Qty Available: (2) ✓ Verified Stock every 24hrs
Questions? (833) 800-7748

All products listed are sold by PLC Department, an independent supplier — not an authorized Allen Bradley distributor. Covered by our 1-year warranty. By purchasing you acknowledge our full disclaimer. Read & agree ↓

Ships from Texas, USA
Same-day by 1 PM CST
Tested & inspected
Every unit, before it ships
1-year warranty
Backed direct by us
30-day returns
Hassle-free RMA
Stock verified / 24 hrs
Real-time availability
Photos on request
Your exact unit, ~5 min
Trusted By

Product Details

Description · Specifications · Product Overview

Specifications provided for reference. Verify critical details against official manufacturer documentation before installation.

Product Overview

The 1785-LT (Allen-Bradley) is a PLC-5/15 processor module within the legacy PLC-5 family. It functions as the central logic controller managing local and remote I/O via built-in communication interfaces, supporting up to 512 total I/O points. Typical use cases include module-level control in manufacturing systems, interfacing with remote I/O racks, and integration with HMI or SCADA systems via Data Highway Plus (DH+) and Remote I/O protocols.

Best Suited For

  • Installation in 1771 I/O chassis as resident or complement
  • Scenarios requiring up to 512 inputs and 512 outputs
  • Remote I/O expansion across up to three external racks
  • Integration with DH+ networks and local I/O racks
Total I/O capacity
512 I/O
Embedded memory
6 K Words (expandable to 14 K Words)
Communication ports
DH+ and Remote I/O built-in
Hardware addressing
2-slot, 1-slot, ½-slot

Technical Specifications

I/O & Electrical

Total I/O capacity
512 inputs and 512 outputs (any mix)
Max total I/O
3 072 any mix (distributor-listed)

Communication & Power

Embedded communication
Standalone scanner (local/remote I/O) and DH+

Physical & Environmental

Weight
3.06 lbs (1.39 kg)
Operating temperature
0-60 °C (32-140 °F)
Storage temperature
-40-85 °C (-40-185 °F)
Relative humidity
5-95% (non-condensing)
Shock (operating)
30 g, 11 ms
Shock (non-operating)
50 g, 11 ms

Certifications

UL ListedCSA Classified for Class I, Division 2, Groups A-DCE

1-Year Warranty

Every tested unit is backed by our free 1-year PLC Department warranty, direct from us.

Fast Shipping

Free ground shipping. Orders by 1 PM CST ship same-day, with overnight available.

USA Stock

Sourced and shipped from Texas, USA. Never anonymous overseas marketplace stock.

30-Day Returns

Hassle-free RMA. If the part is not right for your application, send it back within 30 days.

Reseller Options →

Resellers welcome. Reach out for volume pricing and we will get you set up.

Talk to a Real Person

Fast answers on stock, revisions, and shipping. (833) 800-7748 or live chat.

PLC Department customer reviews from maintenance and engineering teams

Trusted by 1000s of teams who keep plants running

From maintenance managers and controls engineers to Fortune 500 manufacturers, teams across America count on PLC Department. Years of customer care, every unit bench-tested before it ships, and real people on the phone when a line is down. Our job is simple: get you back up and running, fast.

Read customer reviews →

We're here to support your business
Call, email, or chat anytime

Rockwell Automation documentation

Access official manuals, datasheets, and lifecycle information for this part directly from Rockwell Automation.

Visit RockwellAutomation.com →

Must Read: Disclaimer

PLC Department sells surplus and refurbished industrial automation products, including but not limited to programmable logic controllers (PLCs), which are sourced exclusively through independent third-party channels. PLC Department is not an authorized distributor, reseller, or representative of any manufacturer listed on this website, including Rockwell Automation or its Allen-Bradley brand. All product warranties, where offered, are provided solely by PLC Department and not by the original manufacturer.

Any reference to manufacturer names, logos, trademarks, or product identifiers is for identification and compatibility purposes only. All such trademarks and brand names are the property of their respective owners, and this website is not affiliated with, endorsed by, or approved by any manufacturer referenced herein.

The products offered for sale may be used or surplus and may contain older date codes, be of earlier series or versions, or differ in appearance or features compared to products available through factory-authorized distribution channels. The presence, version, or functionality of firmware, if any, on programmable devices such as Allen-Bradley PLCs is not guaranteed. PLC Department makes no representation or warranty regarding:

PLC Department does not obtain or supply firmware on behalf of customers. It is solely the customer's responsibility to ensure legal and compliant use of any firmware or software associated with products purchased through this site, including compliance with any applicable license agreements or manufacturer policies.

Products listed on this site may vary in country of origin, packaging, language, accessories, and included materials. Any quality control, testing, certification, or warranty previously associated with the manufacturer does not apply unless explicitly stated by PLC Department.

By purchasing through this website, you acknowledge and agree to these terms.