Interface Converter, RS-422 to RS-232

  • Converts RS-422 to RS-232
  • Bi-directional
  • Compact RJ-45 barrel case
  • RS-232 interface is EIA-TIA 561 pinout (RS-232 on an RJ-45 connector)
  • Designed for DCB SR multiplexers, but used in other applications
  • Use for any RS-422 to RS-232 aysnc conversion
  • RS-232 Line powered or external adapter powered
  • Industrial temperature version available

Download a printable (.pdf) data sheet



The DCB RS-422 to RS-232 interface converter is just 1.75" long and 1" in diameter. It is available in a line powered unit that is powered by +12 Vdc on pin 1 or powered by an external 120Vac wall-mount power supply. While designed for use with the DCB SR multiplexers, it is suitable for converting RS-422 to RS-232 with any manufacturers' equipment. The DCB converter requires a plus DC voltage on pin one of the RS-232 connector to power the circuit. The unit will convert RS-232 to RS-422, RS-530, and V.35 (transmit and receive data only).

For more demanding applications, our industrial rated RS-422 to RS-232 converters may be more appropriate. They were designed to a wider temperature range, various power supply voltages, and include screw-down terminals. Information on those products is here.

Typical Application from DCB SR mux to an RS-422 terminal, showing pinouts:

RS-561 Interface Pin # RS-232 end of converter RS-422 end of converter
DSR 1 -----> 1 Positive 12Vdc voltage required, 5 - 10 ma.
(on line-powered unit)
1 n/c
DCD 2 2 n/c 2 n/c
Busy 3 3 n/c 3 OUTPUT Rx Data -
Sig Gnd 4 4 Sig Gnd 4 INPUT Tx Data +
Rx Data 5 ----> 5 Rx Data INPUT 5 INPUT Tx Data -
Tx Data 6 <--- 6 Tx Data OUTPUT 6 OUTPUT Rx Data +
CTS 7 n/c n/c
RTS 8 n/c n/c

"n/c" refers to "no connection"

The above arrows show the signal direction. Note that the RS-422 leads are balanced, with 2 OUTPUT wires (pin 3 is -, pin 6 is +), and 2 INPUT wires (pin 4 is +, pin 5 is -).

Pin 5 of the RS-232 side RJ-45 connector is data INPUT to the converter, Pin 6 of the RS-232 connector is data OUTPUT from the converter.

Typical application using a PC 9 pin serial port:
9 pin serial port RJ-45 connector at
RS-232 end of converter
RJ-45 connector at
RS-422 end of converter
4 - DTR -> 1 = +6 to +12 Volts DC required from RS-232 device unless DC adapter is used. Typical current is 9 ma. 1 - n/c
2 - n/c 2 - n/c
3 - n/c 3 OUT Rx Data -
5 - Signal Ground 4 - Signal Ground 4 IN<- Tx Data +>
3 - Rx Data -> 5 - Rx Data IN 5 IN<- Tx Data ->
2 - Tx Data <-> 6 - Tx Data OUT<-> 6 OUT Rx Data +
7 - n/c 7 - n/c
8 - n/c 8 - n/c

On the interface converter, the label reads "RS-232 to RS-422". The end labeled "RS-232 " is electrically RS-232. The end labeled "RS-422" is electrically RS-422.

Pin Numbering from the cable perspective

Pin Numbering from the connector perspective


RJ45 version - Two RJ-45 modular 8-conductor jacks
1.75" long, 1" diameter
Txd and Rxd lines ONLY are converted, Control leads are not passed through the converter
Temperature range 0 to +70 C standard, -40 to +85 C Industrial model

How to Order

Is this going into a critical application? Check out the industrial version - click here!

Item Number Description Price Buy Now!
9802034 RS-422 to RS-232 Interface Converter (powered from RS-232 lead) $ 44 Qty:
9802044 RS-422 to RS-232 Interface Converter with 120VAC- DC adapter $ 66 Qty:
9802045 RS-422 to RS-232 Interface Converter with 240VAC- DC adapter $ 66 Qty:
9802059 RS-422 to RS-232 Interface Converter Rated -40 to +85C (powered from RS-232 lead)(/a) $ 60 Qty:
9802057 RS-422 to RS-232 Interface Converter -40 to +85 C w/ 120 V Power adapter $ 83 Qty:

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Dewey, Il 61840
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