Product Details
Product Overview
The Allen Bradley 1769-ASCII serves as a specialized communication bridge for the CompactLogix platform. This module enables PLC systems to interface directly with ASCII-based serial devices such as barcode scanners, weigh scales, printers, and vision sensors. It manages complex character strings and handshaking protocols independently, offloading the processing burden from the main controller CPU. We supply this unit as 100% Brand New and Original, ensuring seamless serial integration for your automated data acquisition tasks.
Technical Specifications
The 1769-ASCII provides flexible serial connectivity through the following hardware parameters:
| Feature | Specification |
| Manufacturer | Allen Bradley |
| Product Line | CompactLogix |
| Module Type | ASCII Communication Interface |
| Serial Channels | 2 Full Duplex (RS-232, RS-422); 2 Half Duplex (RS-485) |
| Power Rating | 425mA @ 5V DC |
| Isolation Voltage | 30V Continuous |
| Input/Config Words | 108 Input Words / 31 Configuration Words |
| Hardware Handshaking | RTS/CTS Supported |
| Operating Temperature | 0 to 62 °C (32 to 140 °F) |
| Power Dissipation | 2.13 Watts (Max) |
| Distance Rating | 4 (Power Supply Distance) |
Engineering Advantages
The 1769-ASCII addresses specific technical hurdles in industrial serial communication:
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Protocol Independence: The module handles raw ASCII data streams, allowing engineers to write custom parsing logic for non-standard serial devices. This eliminates the need for external third-party protocol converters.
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Robust Handshaking: Integrated RTS/CTS hardware handshaking manages data flow between the PLC and peripheral. This prevents buffer overflows and data loss during high-speed transmissions or when communicating with slow-response devices.
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Multi-Standard Support: A single module supports RS-232, RS-422, and RS-485 electrical interfaces. This flexibility allows a single spare part to cover multiple field applications, from short-range point-to-point links to long-range multi-drop networks.
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Diagnostic Transparency: The module reports real-time status flags including TX/RX FIFO overflows and parity errors. These diagnostics allow maintenance teams to pinpoint wiring issues or baud rate mismatches immediately without advanced serial analyzers.
FAQs
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How many 1769-ASCII modules can I install in one CompactLogix rack?
The power supply distance rating for this module is 4. You must install the 1769-ASCII within four slots of the 1769 power supply to ensure sufficient current across the backplane. Always calculate the total backplane current draw to prevent system instability.
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Which cable should I use for RS-485 configurations?
We recommend the Belden 8761 shielded twisted-pair cable. Proper shielding protects the 3…25V DC serial signals from electromagnetic interference (EMI) commonly found in industrial environments near high-power motor drives.
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Does this module support Modbus RTU?
The 1769-ASCII is designed for generic ASCII string manipulation. While you can technically write ladder logic to handle Modbus RTU frames, the 1769-SM2 or a dedicated ProSoft module typically provides a more efficient solution for Modbus-specific protocols.
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How does the module handle large data packets?
The module utilizes 108 input words to buffer incoming character strings. It assigns a unique Transaction ID (0–255) to each data transfer, allowing the controller to synchronize and verify every message received from the serial device.
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
PLC vs. HMI: Distinguishing the Brain from the Interface in Industrial Automation
In the realm of industrial automation, distinguishing between a Programmable Logic Controller (PLC) and a Human-Machine Interface (HMI) is fundamental. While both devices work in tandem, they serve distinct purposes. The PLC acts as the "brain" of the operation, executing logic, whereas the HMI serves as the "eyes," allowing operators to monitor and interact with the system. Understanding this synergy is essential for any professional designing robust factory automation solutions.
Selecting the Right Industrial Automation Solution for Modern Manufacturing
Choosing an effective industrial automation system starts with a thorough process audit. You must identify tasks that are repetitive, labor-intensive, or prone to human error. Not every process requires high-level automation; therefore, prioritize operations that directly impact throughput and quality. By scoping your needs accurately, you avoid over-investing in unnecessary technology. A balanced approach ensures that your capital expenditure aligns with measurable gains in operational efficiency.
Implementing FIFO and LIFO Data Sequencing in PLC Programming
Data management serves as a cornerstone of modern industrial automation. Whether tracking materials on a conveyor or managing batch sequences in a process, engineers frequently rely on sequential logic. Two primary structures—First-In-First-Out (FIFO) and Last-In-First-Out (LIFO)—form the bedrock of this data handling. Mastering these blocks allows programmers to optimize complex machine operations efficiently.