WSAL23376 – RS232 TO RS485 (B)/en

Documentation notice: This technical documentation was independently rewritten from an archived supplier source. Check technical details and commands against the product version and manufacturer documentation before use.

Summary

The RS232 TO RS485 (B) is an active, digitally isolated bi-directional serial converter. It converts RS232 signals into balanced differential RS485 signals and supports reliable transmission at 300–115200 bps. The unit features integrated 600 W lightning/surge protection, a switchable 120 Ω termination resistor, and DIN-rail mounting for industrial use.

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Technical overview

Active digital isolation with integrated power-supply and signal isolation; no external power supply needed for the isolated terminal.
Supply voltage: 6–36 V DC via screw terminals; reverse-polarity protection included.
Reliable communication range: 300–115200 bps; maximum rate can reach 921600 bps, but only the recommended range is considered stable.
RS232 side: screw terminals, point-to-point half-duplex, range approx. 15 m.
RS485 side: screw terminals, point-to-multipoint (up to 32 nodes; repeater recommended beyond 16 nodes), range approx. 1200 m.
Integrated TVS suppresses voltage spikes; additional resettable fuse and protection diodes provide over-current and over-voltage protection.
Optional 120 Ω termination resistor on the RS485 side, enabled by a switch; recommended to enable at the start and end points of the bus segment.
ABS DIN-rail-mount case, dimensions L×W×H: 91.6 × 23.3 × 58.7 mm; operating temperature −15 °C to +70 °C.

Notes and version constraints

RS485 is half-duplex: simultaneous sending and receiving is not possible; observe test sequence.
Correct GND wiring depends on the application: in simple scenarios without a shared reference or interference risk, GND may remain unconnected; in complex systems with high signal-integrity requirements, connect GND according to specification.
If malfunction occurs: verify supply voltage with a multimeter (6–36 V), check TXD/RXD cross-wiring, connect RS485 A-A/B-B correctly; the 120 Ω resistor is off by default.
The module does not support direct Modbus read/write or protocol conversion; it only performs transparent data forwarding at the physical layer.
Beyond 16 RS485 nodes, using a repeater is recommended to ensure reliability.

Source and revision record

RS232 TO RS485 (B) - Waveshare Wiki
Source revision: 88232
Captured: 2026-09-04T02:53:25+00:00
SHA-256: 2de1fe6abac271de912c6d721b86757f25ec953f038dec2123f17b8485785548