Teledyne 4040 - Methane / Nonmethane analyzer - Manual (Page 35)

Installation
Teledyne Analytical Instruments 35
3.3.4 RS-232 Port
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. It requires a standard 9-pin D connector.
Input: The input functions using RS-232 that have been implemented
to date are described in Table 3-7.
Table 3-8: Commands via RS-232 Input
Command Description
AS Immediately starts an autospan.
AL Immediately revert to Analyze (CH4 Mode)
RL Change to Manual Range LOW
RM Change to Manual Range MEDIUM
RH Change to Manual Range HIGH
RA Change to Manual Range AUTO
Implementation: The RS-232 protocol allows some flexibility in its
implementation. Table 3-9 lists certain RS-232 values that are required
by the Model 4020 implementation.
Table 3-9: Required RS-232 Options
Parameter Setting
Baud 2400
Byte 8 bits
Parity none
Stop Bits 1
Message Interval Sent at the end of each cycle.
3.3.5 Supporting Gases
Normally, four supporting gases of different composition (see
Section 4.1: Equipment) will be required to operate the analyzer. The
recommended composition of these gases is specified in the Application
Data section of the Appendix. The gases should be supplied from
cylinders that are equipped with the type of regulator specified in the
aforementioned sections.