Tips & Tricks - Advantech DLoG MTC 6 Series User Manual

Please note that you have to configure the scanner correctly to
NOTICE:
RS-232 and the above set BAUDrate following the scanner
Property
manufacturer's guidelines. Otherwise the software wedge will not
damage
function properly.
11.4. Tips & tricks
Note that according to the EIA-232-E specification, the maximum cable length is 15 m at
19,200 bps.
By using a correctly terminated twisted-pair cable, however, up to 1,200 m at 100 kbps
can be achieved according to the EIA-422-A specification. With a data rate of 1 Mbps
and a high-quality cable, it is possible to reach cable lengths of up to approximately 400
m.
Malfunctions in the RS-232 connections are frequently caused by ground loops. If both
end devices establish a ground connection via RS-232 but do not share the same ground
potential in their power supply circuits, then compensation currents may result. This is
particularly noticeable with long cables.
These compensation currents, which are also present at the ground point of the RS-232
connection, may significantly degrade signal quality and effectively stop the data flow. In
challenging environments, electrically-isolated connections (via external converters) or
differential systems (RS-422/485 port) are strongly recommended.
MTC 6 Series User's Manual V2.00
Serial port
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