Allen-Bradley 1746-BAS SLC 500 BASIC Module

Product Overview

The Allen-Bradley 1746-BAS functions as a high-performance, programmable co-processor for the SLC 500 platform. This module executes custom BASIC programs independently of the main CPU, allowing it to handle complex mathematical calculations, data logging, and interfacing with non-Rockwell serial devices like bar code scanners, printers, and weight scales. Despite the manufacturer’s discontinuation in 2013, we provide this unit as 100% Brand New original stock. This ensures your legacy systems regain the exact serial communication capabilities required without the hardware instability of used components.

Technical Specifications

The 1746-BAS provides robust hardware resources to manage asynchronous serial communication:

Engineering Advantages

• Offloads CPU Processing: The 1746-BAS executes complex string manipulations and floating-point math locally. This offloading prevents the SLC 500 processor scan time from increasing, maintaining high-speed control for the rest of the chassis.

• Versatile Physical Interface: The module supports multiple electrical standards including RS-232, RS-422, and RS-485. This flexibility allows the module to communicate with long-distance serial devices (up to 4000 feet on RS-422) or standard short-range PC peripherals.

• Non-Volatile Data Security: The 24K byte battery-backed RAM protects your custom scripts and critical buffer data during power cycles. This eliminates the need for manual program reloads following a facility power outage.

• Real-Time Diagnostics: Dedicated LED indicators on the front panel provide immediate visual feedback regarding port activity and module health. This allows maintenance teams to troubleshoot communication bottlenecks without connecting a laptop.

FAQs

• Q: Can the 1746-BAS communicate with a Modbus device?

• A: Yes. While it does not support Modbus natively out-of-the-box, you can write a BASIC program to handle the Modbus RTU protocol frames through the serial ports.

• Q: Does this module require a specific slot in the SLC 1746 chassis?

• A: No. You can install the 1746-BAS in any available I/O slot. However, ensure the power supply in the chassis provides sufficient current for the co-processor and your existing I/O.

• Q: Is the battery included with this "Brand New" module?

• A: We supply the module in its 100% Brand New factory state. We recommend verifying the battery voltage before commissioning, as these units originate from surplus factory stock and may require a fresh CR2032 or equivalent for optimal backup life.

• Q: How do I transfer my BASIC program to the module?

• A: Use a terminal emulation program on a PC connected via the PRT1 port. The module enters "Command Mode" upon power-up or break-signal, allowing you to upload or edit the BASIC source code.