Allen-Bradley 1746-BAS-5/02 SLC 500 BASIC Module

Configured for external device communication and embedded BASIC execution in SLC 500 backplane environments, the Allen-Bradley 1746-BAS-5/02 (1746-BAS-5/02 BASIC module) provides direct physical/electrical execution for serial data handling and user program runtime within SLC 500 controller chassis.

Suffix Breakdown & Model Matrix

The 1746-BAS-5/02 is a single-part configuration within the SLC 500 BASIC module family. No documented hardware segmentation or functional suffix branching is defined beyond the catalog revision identifier. All communication ports and memory resources are fixed at module level.

Hardware Specifications

PLC Backplane Execution & Serial Protocol Handling

The module executes BASIC runtime tasks through SLC 500 backplane communication cycles, synchronizing instruction-level data exchange with processor scan timing. RS-232/422/485 ports support DF1 protocol framing and asynchronous serial buffering for external HMI, printer, and modem interfaces. DH-485 channel routing requires 1747-AIC coupling for network topology extension.

Backplane current draw is split across 5 VDC logic rail and 24 VDC interface rail, requiring chassis-level power budget allocation during mixed I/O configuration. Signal integrity is maintained through standard industrial grounding practices, with serial port isolation dependent on system cabling topology.

Frequently Asked Questions (FAQ)

Q: Can the 1746-BAS-5/02 execute BASIC programs while communicating on multiple ports simultaneously?
A: Yes. The module supports concurrent task scheduling across PRT1, PRT2, and PRT3 with internal buffer arbitration tied to backplane scan cycles.

Q: Does DH-485 communication operate natively on this module?
A: DH-485 is supported via PRT3, but physical network access requires an external 1747-AIC interface module.

Q: What is the effect of backplane voltage fluctuation on module execution?
A: Voltage variation on the 5 VDC backplane rail directly impacts CPU-level instruction timing stability and may trigger FAULT or BAT LOW indicators.

Field Installation Guidelines

Module insertion must be performed with chassis power removed to avoid backplane bus arcing. Ensure edge connector alignment with SLC 500 slot rails before full seating. RS-485/422 cabling should follow shielded twisted-pair routing with single-point earth grounding at cabinet entry. DH-485 segment wiring must maintain proper termination resistance and isolation via 1747-AIC interface.

Battery-backed RAM retention depends on correct battery installation prior to first power-up cycle. Avoid routing serial communication cables parallel to high-voltage motor leads to minimize induced noise coupling.