Allen-Bradley 1785-L86B PLC-5/86 Processor 100K Words

1785-L86B Allen-Bradley PLC-5/86 Standard Controller

Product Introduction

The 1785-L86B from Allen-Bradley represents a powerful and mature control solution within the PLC-5 product family. Designed as a standard processor, this module handles complex automation tasks with ease. It offers substantial memory capacity and extensive I/O support, making it suitable for large-scale manufacturing lines, process control, and material handling systems. Furthermore, its robust construction ensures stable operation even in challenging factory floor conditions. Users appreciate its balance of processing power and proven reliability.

Key Technical Specifications

This controller packs significant capabilities into a single 1771 chassis slot. First, its maximum user memory reaches 100 kilowords, providing ample space for large ladder logic programs and data tables. The memory type is battery-backed static RAM, which retains programs during power outages. Additionally, the 1785-L86B supports EEPROM backup using compatible modules like the 1785-ME16, 1785-ME32, 1785-ME64, or 1785-M100 for permanent program storage.

The I/O system is exceptionally flexible. This processor handles a maximum total I/O count of 3072 points in any combination. Alternatively, it supports 3072 inputs plus 3072 outputs in complementary mode. Specifically, the analog I/O capacity also reaches 3072 channels, accommodating extensive analog signal processing. For system expansion, the 1785-L86B manages up to 93 I/O chassis links, with each link supporting up to 32 universal remote chassis.

Communication capabilities include one RS-232-C/422-A/423-A port for programming and interfacing with operator panels. Moreover, it features a control coprocessor expansion port for enhanced functionality. The controller communicates over Data Highway Plus and Remote I/O networks, ensuring seamless integration with other Allen-Bradley devices. Notably, the I/O scan time varies by baud rate: 10 ms at 57.6 kbit/s, 7 ms at 115.2 kbit/s, and 3 ms at 230.4 kbit/s, enabling fast response in time-critical applications.

Mechanical and Environmental Ratings

The 1785-L86B is built to endure industrial conditions. It operates reliably within a temperature range of 0°C to 60°C (32°F to 140°F) and a non-condensing humidity range of 5% to 95%. For storage, it withstands temperatures from -40°C to 85°C (-40°F to 185°F).

Mechanically, the module handles operational shock up to 30G and vibration of 2G at frequencies from 10 to 500 Hz. This ruggedness minimizes failure risks due to machinery vibrations or accidental impacts. The controller draws a backplane current of 3.3 amperes at 5V DC and dissipates approximately 17.3W of heat during normal operation. Isolation testing confirms 500V for 60 seconds between communication ports, and 300V for 60 seconds between ports and the relay cartridge, ensuring electrical safety.

Installation and Addressing Guide

Installing the 1785-L86B is straightforward. Simply insert it into any available slot of a 1771 I/O chassis. The controller automatically configures itself upon power-up. For hardware addressing, it supports three distinct modes: 2-slot, 1-slot, and ½-slot addressing. These options provide flexibility in mapping I/O modules to memory addresses, accommodating various rack configurations and module densities.

Specifically, the 1785-L86B works with a wide array of 1771 I/O modules, including 8-point, 16-point, 32-point, and intelligent analog or specialty modules. This compatibility simplifies system upgrades or expansions. Remember to install a 1785-RC relay cartridge if you need dry contact outputs for interfacing with external equipment. Additionally, use the EEPROM modules listed above to back up your application program for disaster recovery.

Programming and Software Support

Programming the 1785-L86B is accomplished through Rockwell Automation's RSLogix 5 software. This intuitive environment supports multiple languages, including Ladder Logic, Sequential Function Chart, and Structured Text. Therefore, programmers can choose the best language for each control task. The protected memory feature prevents unauthorized or accidental program alterations, enhancing system security and uptime.

Packaging List

Your shipment of the 1785-L86B includes the following items:

• One Allen-Bradley 1785-L86B PLC-5/86 Standard Processor module

• One factory-installed battery for SRAM retention

• Product installation and setup quick-start guide (printed)

• Anti-static protective packaging

Note: Programming software, communication cables, and mounting hardware are sold separately.

Shipping Information

We ship all orders via trusted global carriers: FedEx, UPS, or DHL. Standard delivery times range from 3 to 7 business days depending on your location. Expedited shipping options are available upon request. All items are carefully packaged to prevent damage during transit.

Frequently Asked Questions (FAQ)

1. What is the maximum memory capacity of the 1785-L86B processor?
The 1785-L86B provides 100 kilowords of battery-backed static RAM for user programs and data storage. This capacity is sufficient for large-scale automation applications.

2. Can I use this processor with existing 1771 I/O modules?
Yes, absolutely. The 1785-L86B is fully compatible with all standard 1771-series I/O modules, including 8-point, 16-point, 32-point, and intelligent analog modules.

3. How do I back up my program on the 1785-L86B?
You can back up your program using optional EEPROM modules such as the 1785-ME16, 1785-ME32, 1785-ME64, or 1785-M100. These modules store the program permanently without battery power.

4. What programming software works with the 1785-L86B?
Rockwell Automation's RSLogix 5 software is the recommended programming tool. It supports Ladder Logic, Sequential Function Chart, and Structured Text languages.

5. What is the typical delivery time for this product?
We ship worldwide using FedEx, UPS, or DHL. Delivery usually takes 3 to 7 business days, depending on your destination and chosen shipping method.