How to Test RS422A Serial Datacom Interfaces with MTX150?

RS422A and RS485A use standard V.11 balanced signal pairs, but they may be found in a variety of connectors. So, a custom adapter cable is usually required.

VeEX's MTX150 test set supports Asynchronous RS422A and RS485A full-duplex interface testing, in DTE (terminal) mode. However, due to the variety of connectors used by network equipment vendors, VeEX doesn't offer adapter cables for these datacom interfaces. Being only two twisted pairs, RS422A and RS485A adapters are simple to assemble.  

The DVI connector pinout is displayed below for reference. Since RS422A and RS485A use V.11 balanced signals, make sure the + and - (A and B) signals are connected to the same twisted pair, to maintain signal integrity. 

If using any of the balanced (V.11 type) datacom cables provided by VeEX, refer to the table on the test set's GUI.

MTX150 RS422A datacom configuration, with pinout tables

Refer to the DCE port or device under test (DUT) documentation to properly wire the connector at the other end.

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