Allen-Bradley 1785-L40L PLC-5/40L Standard Processor

Product Overview

The 1785-L40L from Allen-Bradley is a standard processor for the PLC-5/40L series. This controller manages up to 2048 total I/O points. It features 48 Kilowords of user memory backed by static RAM. The processor draws 3.3A from a 5V DC backplane. It supports extended local I/O links for flexible system design.

This module fits into a 1771 I/O chassis. It uses a single slot for installation. The controller communicates via Data Highway Plus and Remote I/O networks. It includes one RS-232-C/422-A/423-A port. A control coprocessor expansion port is also available.

Application Scenarios

Use the 1785-L40L in manufacturing plants and process control systems. It works well for material handling, packaging, and assembly lines. The processor can coordinate up to 61 I/O chassis. It supports 16 extended local chassis and 32 universal remote chassis. This makes it ideal for large distributed automation systems.

Industries like automotive, food and beverage, and pharmaceuticals benefit from its reliability. The controller handles 8, 16, and 32-point I/O modules. It also connects to intelligent modules from Bulletin 1771, 1794, 1746, and 1791.

Technical Specifications

• Module Type: Standard Processor
• Processor: PLC-5/40L
• Max User Memory: 48 Kilowords
• Battery-Backed Static RAM: Yes
• Max Total I/O: 2048
• Max Analog I/O: 2048
• Backplane Current: 3.3A at 5V DC
• Power Dissipation: 17W
• I/O Scan Time: 0.5 ms per rack (ext. local), up to 10 ms at 57.6 kbits/s
• Communication Ports: DH+ / Remote I/O configurable
• Weight: 1.42 kg
• Certifications: UL, CE, C-TICK, CSA

Installation & Maintenance Guide

Install the 1785-L40L in the leftmost slot of a 1771 I/O chassis. Ensure the backplane power supply can provide 3.3A at 5V DC. Use the correct slot addressing mode: half-slot, single-slot, or double-slot. Connect communication cables to the DH+ / Remote I/O port. For extended local I/O, use a compatible adapter.

Maintenance includes periodic battery replacement for memory backup. Use an Allen-Bradley compatible battery-backed memory module. Keep the controller within 0 to 60°C operating temperature. Avoid exposing it to moisture or excessive vibration.

Packing List

• 1x Allen-Bradley 1785-L40L PLC-5/40L Processor
• 1x User Manual (digital or printed)
• 1x Battery Backup (if applicable)
• Mounting brackets and screws

Shipping is via FedEx, UPS, or DHL depending on your location. Each unit is packed securely in an anti-static bag and foam-lined box.