Teledyne 4020 - Hydrocarbon analyzer - Manual (Page 42)

Installation Model 4020
Teledyne Analytical Instruments 26
Table 3-8: Commands via RS-232 Input
Command Description
as<enter> Immediately starts an autospan.
az<enter> Immediately starts an autozero.
Implementation: The RS-232 protocol allows some flexibility in its
implementation. Table 3-8 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 2 seconds
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.
CAUTION: UNDER NO CIRCUMSTANCES SHOULD YOU
EMPLOY A REGULATOR THAT IS NOT EQUIPPED
WITH A METALLIC DIAPHRAGM ANYWHERE IN THE
SYSTEM.
The regulators should be inspected prior to installation to be sure
that they are oil-free. Failure to comply with these directives will result
in a constant drift in analyzer output, as organic compounds will outgas
into the plumbing system at a rate that is related to the ambient
temperature. Use 316 stainless steel, dual-stage regulators only in fuel,
sample, and blanket air lines; shutoff valves should be used downstream
from each regulator.