Servomex SERVOPRO Plasma, Operator'S Manual

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Plasma Gas Analyzer
22 02001001A_9
4.2.6 RS232 connection (option)
WARNING
The RS232 communications terminals are separated from the analyzer
main circuit by reinforced insulation. The terminals must only be
connected to circuits that are themselves separated from mains
voltages by an isolation method that provides at least
this level of protection.
WARNING
Ensure that the electrical installation of any equipment connected to the
analyzer conforms to all applicable local and national electrical safety
requirements.
CAUTION
To comply with EMC requirements, screened cables must be used to connect
the RS232.
With this option installed, this analyzer retransmits the operating parameters and
process values to a remote computer through a serial link. The computer is connected to
the analyzer by the mean of a DB-9 RS-232C (Null-modem) cable. The computer must
have appropriate software to read the data transmitted by the analyzer.
The RS-232 port on the analyzer is driven by an opto-isolator/convertor.
All precautions are taken to give a reliable serial transmission, even if the opto
isolator/converter system provides a barrier against noise, transient and ground loop, it
cannot support high voltage differences between two different floating systems. For this
reason, the remote computer and the analyzer must be properly grounded (ground at
same potential).
The standard RS-232C specifications stipulate a maximum distance of 15 metres
between two systems. But, if you are using good communications cable (good shielding
and low capacitance) longer distances may work successfully.
A RS-232C null modem DB-9 cable is supplied with the analyzer. This allows direct
connection to a personal computer serial port.