User Manual

3-5
Percent Oxygen Analyzer Installation 3
Teledyne Analytical Instruments
3.3.1 RS-232 Port Option
The digital signal output is a standard RS-232 serial communications
port used to connect the analyzer to a computer, terminal, or other digital
device. The pinouts are listed in Table 1.
Table 1: RS-232 Signals
RS-232 Sig RS-232 Pin Purpose
RD 2 Received Data
TD 3 Transmitted Data
COM 5 Common
The data sent is status information, in digital form, updated every two
seconds. Status is reported in the following order:
• The concentration in percent
• The range in use
Each status output is followed by a carriage return and line feed.
The RS-232 protocol allows some flexibility in its implementation.
Table 2 lists certain RS-232 values that are required by the 3300PB imple-
mentation.
Table 2: Required RS-232 Options
Parameter Setting
Baud 2400
Byte 8 bits
Parity none
Stop Bits 1
Message Interval 2 seconds
The RS232 terminals must not be connected
to any AC line source, or any source of
hazardous voltage.
3.4 Gas Connections
The standard Model 3300PB has two inlets and one outlet fixture only.
Calibration gasses can be connected into the "Span" inlet. All of the sample
connections are 1/8 inch brass fittings.