Allen-Bradley 1746-BAS SLC 500 BASIC Module

Product Overview

The Allen-Bradley 1746-BAS functions as a highly versatile co-processor for the SLC 500 platform. This module executes complex mathematical calculations and custom serial communication strings independently of the main PLC processor's scan cycle. It bridges the gap between standard ladder logic and advanced data manipulation, allowing engineers to interface directly with specialized peripheral devices such as barcode scanners, scales, and non-Rockwell HMI terminals. We offer this unit as 100% Brand New and Factory Original, ensuring peak performance for your legacy system maintenance.

Technical Specifications

Engineering Advantages

• Custom Protocol Development: The 1746-BAS executes user-written BASIC code to handle ASCII data streams. This capability allows the SLC 500 to communicate with virtually any serial device, even those lacking native Rockwell drivers.

• Off-Scan Processing: By offloading complex calculations and serial polling to the 1746-BAS, the main CPU maintains a faster and more consistent scan time. This architecture optimizes the performance of high-speed machine control tasks.

• Flexible Interface Selection: The module features dual serial ports with switch-selectable electrical interfaces (RS-232, RS-422, or RS-423). This versatility permits long-distance communication (up to 4000 ft via RS-422) without requiring external signal converters.

• Data Integrity Protection: The 24k byte battery-backed RAM secures critical variables and user programs against power loss. This ensures immediate system resumption upon power restoration, preventing the loss of machine calibration or production data.

• Simplified Troubleshooting: Dedicated LED indicators on the front panel provide real-time feedback on module health and port activity. These diagnostics allow technicians to isolate communication errors quickly without deep-diving into the code.

FAQs

• Can I replace a standard SLC I/O module with the 1746-BAS?

  The 1746-BAS occupies a single slot in any standard 1746 chassis. However, it requires specific configuration in the I/O rack within RSLogix 500. Ensure you assign the correct M0 and M1 file lengths to enable high-speed data transfer between the BASIC module and the SLC processor.

• What software do I need to program the 1746-BAS?

  You program the module using PBASIC through a standard terminal emulator (like HyperTerminal or Procomm) connected to the module's serial port. It does not use RSLogix 500 for the internal BASIC logic, only for the backplane data mapping.

• Does this unit come with a battery installed?

  While we supply the module in 100% Brand New condition, we recommend verifying the battery status upon installation. Due to the storage time typical for discontinued parts, replacing the backup battery ensures maximum reliability for your 24k RAM.

• Is this a refurbished unit or new surplus?

  We guarantee that this 1746-BAS is 100% Brand New and remains in its original factory-sealed Allen-Bradley packaging. We do not sell used or "pulled" modules, providing you with a factory-fresh component for your critical infrastructure.