Product Details
Overview
The Allen-Bradley 1785-L20E is a PLC-5/20E Processor Module designed for reliable control and communication within industrial automation environments. As part of the Allen-Bradley PLC-5 family, it provides Ethernet connectivity, advanced memory management, and flexible I/O configuration options, making it suitable for mid-scale automation systems requiring dependable networked control.
Built to withstand harsh operating conditions, the 1785-L20E integrates robust communication ports, high-speed processing, and wide environmental tolerance for demanding manufacturing and process control applications.
Technical Specifications
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Manufacturer: Allen-Bradley (Rockwell Automation)
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Product Line: PLC-5 Series
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Part Number: 1785-L20E
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Processor Type: PLC-5/20E
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Product Type: Programmable Logic Controller Module
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Memory Capacity: 16 Kwords of user memory
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Non-Volatile Backup: Supported with EEPROM modules (1785-ME16, 1785-ME32, 1785-ME64, 1785-M100)
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Battery Type: 1770-XYC, for memory retention
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Protected Memory: Not available
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Total I/O Capacity: 512 I/O points (any mix) or 512 inputs + 512 outputs in complementary mode
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Analog I/O Capacity: Up to 512 points
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I/O Chassis Support: Up to 13 total; 12 remote I/O chassis supported
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Local I/O Racks: Maximum of 4 (addresses 0–3)
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I/O Scan Time per Rack: 10 ms @ 57.6 kbps, 7 ms @ 115.2 kbps, 3 ms @ 230.4 kbps
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Embedded Communication Ports:
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1 x DH+ (fixed)
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1 x DH+/Remote I/O (adapter or scanner)
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1 x Serial port (configurable for RS-232, RS-423, or RS-422A)
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1 x Ethernet interface
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Backplane Current Load: 2.3 A
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Power Dissipation: 12 W typical
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Recommended Power Supplies: 1771-P4S, 1771-P6S, 1771-P4S1, 1771-P6S1
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Control Co-Processor Port: Supported
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Operating Temperature: 0°C to +60°C (32°F to 140°F)
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Storage Temperature: -40°C to +85°C (-40°F to 185°F)
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Humidity: 5% to 95%, non-condensing
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Weight: 3.13 lbs (1.42 kg)
Key Features
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Ethernet-Enabled Control: Integrates Ethernet communication for seamless network connectivity.
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Flexible I/O Management: Supports up to 512 digital and analog I/O channels for scalable automation.
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Durable Architecture: Complies with IEC 60068 environmental testing standards for temperature and shock resistance.
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Comprehensive Communication: Includes DH+, Remote I/O, and multi-protocol serial interfaces.
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Reliable Memory Retention: Battery-backed static RAM and optional EEPROM storage ensure data preservation.
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Compatible Power Options: Works with multiple 1771-series power supplies for design flexibility.
Applications
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Process control systems in manufacturing plants
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Industrial machinery automation
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Material handling systems
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Distributed control networks using ControlNet or Ethernet/IP
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Retrofit and maintenance of legacy Allen-Bradley PLC-5 installations
FAQ
Q: What is the memory capacity of the 1785-L20E processor?
A: It features 16 Kwords of user memory, expandable with external EEPROM modules.
Q: Can this processor communicate over Ethernet?
A: Yes, it has a built-in Ethernet interface in addition to DH+, Remote I/O, and serial communication ports.
Q: Which power supplies are compatible with this module?
A: It supports 1771-P4S, 1771-P6S, 1771-P4S1, and 1771-P6S1 units.
Q: Does it support ControlNet?
A: No, this model supports Ethernet and DH+ networks, not ControlNet.
Additional Information
- 100% Genuine Parts: All products are original and authentic, ensuring reliable industrial performance.
- 30-Day Refund Guarantee: Return any in-stock item within 30 days in original, unopened packaging for a full refund (excluding shipping and fees).
- 12-Month Warranty: Covers defects in materials or workmanship; excludes misuse, normal wear, or unauthorized modifications.
- Worldwide Shipping: We ship via USPS, UPS, FedEx, and DHL. Delivery times vary by country and may be subject to customs or import fees.
- Support & Contact: Technical and warranty assistance is available anytime. Contact us here: Contact.
- Purchase Guidance: Check product specifications and compatibility carefully before ordering to ensure proper application.
Tech & Buying Guide
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Navigating Industrial Automation Failures: Types, Causes, and Mitigation Strategies
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