RS232 to RS485/RS422 Converter

This device implements active isolation conversion from RS-232 to RS-485/422, designed based on FPGA technology and powered by a 2500V isolation voltage DC-DC isolation power supply without using serial port power theft technology. The communication signal is isolated by high-speed optocouplers. The device has built-in circuit short-circuit and data error detection functions. The RS-485/422 interface is protected by three levels of lightning protection and can communicate over distances up to 1800 meters, making it widely used in complex industrial systems.

● The device is designed based on FPGA technology and is capable of automatically generating precise RS485 transmit and receive switching enable signals based on the transmitted data. It can automatically detect and control RS-485 data flow, which performs much better than ordinary enable generation methods using Schmitt triggers.

● It also has a unique interface adaptive technology that allows users to switch between RS-485/RS-422 interfaces without any switch settings.

● The device comes with built-in circuit short-circuit and data error detection functions. It can detect RS485 A-B line short circuit or RS422 T+ and T- short circuit and R+ and R- short circuit. It also has an indicator light to show the detection results and can detect data receiving errors (caused by the longest continuous 0 time greater than the minimum baud rate (300) received when some nodes fail).

● It supports two types of RS232-RS485/422 baud rates: 300-115.2K and 300-921K.

● It uses a 2500V isolation voltage DC-DC power supply to avoid serial port power theft. The communication signal is isolated by high-speed optocouplers.

● The serial port interface has three levels of lightning protection that can withstand up to 6KV impedance (2Ω) standard according to IEC61000-4-5 (8/20μS).

● The device has a wide input voltage range (DC9-55V, AC7-43V), and can automatically detect the polarity of the input DC power supply. It has built-in self-recovering fuses, overload protection, and reverse connection protection.

● It meets industrial level-four electromagnetic compatibility requirements.

● It has excellent lightning protection performance, making it capable of withstanding lightning strikes, high voltage induction, surges, and other interferences.

● Rail or wall-mounted installation.

● Working temperature -40℃~ +85℃.

● The device has passed 100% burn-in tests.

● Serial Interface          

Standard

EIA/TIA-232 RS-232 (ITU-T V.28)

EIA/TIA-422 RS-422 (ITU-T V.11)

EIA/TIA-485 RS-485 (ISO/IEC8284)

Serial port Interface

RS-232: socket DB9;

RS-422: 4-wires;

RS-485: 2/4-wires

Followed: SG = Signal Ground

RS-232: TxD(DB9-2), RxD(DB9-3), SG(DB9-5)

Internal loop: RTS to CTS, DTR to DSR and DCD

RS-422: TxD+, TxD-, RxD+, RxD-, SG

RS-485 4 wires: TxD+, TxD-, RxD+, RxD-, SG

RS-485 2 wires: A (corresponding TX+), B (corresponding TX-), SG

RES+, RES-: terminal 120 Ω match resistance enable. The matching resistance device is built-in, and RES+ and RES- can be short-circuited when in use.

● Indicator Lights           

● Environmental Indicators 

Working temperature: -10 ℃ – +60 ℃

Storage temperature: -40 ℃ – +85 ℃

Working humidity: 0% -95% ( no condensation)

MTBF: > 100,000 hours