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USB to 3-Port RS232/485/422, Isolated

  • Part: MWE820B
  • In Stock


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The MWE820B is an industrial strength very solid and reliable isolated USB to Serial Converter with RS232 / RS422 / RS485 interfaces that requires no external power supply. With its standard DIN rail mount and screw terminals it is a great choice for industrial and commercial applications for general use at point-to-point or point-to-multipoint networks.

After installing the included drivers one (1) virtual COM port automatically shows up in your computer's Device Manager which can be used as if it was a standard built-in COM port.

This USB to Serial converter is build around the high performance industry proven reliable CP2102 processor from Silicon Labs.

Optical isolation is achieved by high speed 6N137 isolation optocouplers from Fairchild Semiconductors, which effectively protects your equipment against all types of high voltage spikes, surges and static electricity.

Another nice feature is that this converter is stackable, meaning you can mount as many units on top of each other as you want, which will save you space on the DIN rail.

This converter will not create 3 individual virtual COM ports in your computer's Device Manager, it will instead create only 1 virtual COM port which can be used for RS232, RS485 and RS422 communication, however all 3 physical ports on the converter can be used at the same time for simultaneous data transfers. This means that data is present on the 3 physical ports at the same time; one port for RS232, one port for RS485 and one port for RS422.

Overall features
  • Combo RS232, RS485 and RS422 converter
  • One COM port available
  • Port powered, no need for external power
  • Optically isolated
  • Screw terminal block
  • WHQL compliant COM drivers included
  • Auto detection of data speed
  • Built-in electrostatic protection
  • Advanced port settings available
  • USB cable included

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Part number MWE820B
Operating system
  • Windows 10, 8.1, 8 (32/64-bit), Windows Server 2012 / R2, Windows 7 (32/64-bit), Windows Server 2008 R2, Vista (32/64-bit), Windows Server 2008 (32/64-bit), XP, Windows Server 2003 (32/64-bit), 2000, (all WHQL compliant). Windows RT as D2XX drivers only.
  • Windows CE v4.2 - 5.2, 6.0, 7.0 and 2013 including: Windows Mobile 2003, 2003 SE, Windows Mobile 5, 6, 6.1 and 6.5
  • Linux (built into kernel 3.0.0-19 and above)
  • Mac OS 8, OS 9, OS X 10.3 to 10.9 and above
  • Android
Processor Silicon Labs CP2102
Power 5VDC provided by USB port
RS232 Interface Screw terminal block
Port 1 RS232 2-wire, output voltage: ~8.9VDC
Port 2 RS422 4-wire Full Duplex, output voltage: ~5.0VDC
Port 3 RS485 2 wire Half Duplex, output voltage: ~5.0VDC
Compatible with Modbus RTU/ASCII, BACnet
Bias resistors Yes
Installation method 35mm standard DIN rail or screws
USB interface Standard Type B Female
Indication LEDs Power, Send and Receive
Serial ports 1 (RS232, RS485 or RS422)
Signals - RS232: TX, RX, GND
- RS485: D+, D-, GND
- RS422: T+, T-, R+, R-, GND
Baud rate 300 to 921600bps
Parity None, Odd, Even, Mark, Space
Data Bits 5, 6, 7, 8
Stop Bits 1, 1.5, 2
TX / RX buffer size 640 byte transmit buffer, 576 byte receive buffer
Flow Control Hardware or Xon / Xoff
COM port accessible by Included virtual COM port drivers
Special features - Event character support
- Line break transmission
Optical Isolation 700V continuous and 3500V spike
Electrostatic (ESD) protection 15KV/ 600W/ms high voltage protection
Current draw Static: less than 80mA. Dynamic average: less than 150mA
Dimensions 102mm x 69mm x 33mm
Interface compliance USB1.1,2.0,3.0, EIA/TIA RS-232
Regulatory compliance FCC, CE and RoHS
Working temp –40 to +85 °C
Warranty 1 year limited warranty

For alternative USB to serial solutions please see our full selection of USB to Serial RS232 adapters

Read the Review
Date Added: 11/14/2014 by John Marcus
5 of 5 Stars5 of 5 Stars
Works! thanks for the quick service

Read the Review
Date Added: 09/02/2013 by Stephen Morris
5 of 5 Stars5 of 5 Stars
I have been comparing several of these multi-port converters from different manufacturers and I foun...

Read the Review
Date Added: 07/12/2011 by Craig Nauman
4 of 5 Stars4 of 5 Stars
Works as described. A good device for a resonable price.

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Quick Tip!

The Multi-port USB to Serial Converter

A multi-port USB to Serial Converter is a converter which can create more than one COM port. Some USB to Serial converters can even be used with RS232, RS485 and RS422 at the same time. You might not often need all serial interfaces at the same time however using one at a time is often convenient if you have different types of devices.
So by using a multi-port USB to Serial converter you can save time and money instead of having to buy multiple single port converters. Another advantage of a multi-port USB Serial converter is that it uses the same software drivers for all interfaces so you do not waste time on installing several different manufacturers driver software. This is also an advantage since you avoid driver conflicts by using same converter.

For alternative solutions please see our selection of USB serial adapters.


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