Teledyne 4020 - Hydrocarbon analyzer - Manual (Page 43)

Total Hydrocarbon Analyzer Installation
Teledyne Analytical Instruments 27
Place the supply cylinders as close to the analyzer as possible, and
interconnect them to the analyzer with new tubing. Be sure that all
plumbing connections are free of leaks.
Note: Use only stainless steel tubing throughout the system.
Consult the assembly, piping, outline drawings, and any
Addenda included with this manual to determine if special
conditions apply.
3.3.5.1 S AMPLE G AS
An oil-free, metallic diaphragm regulator must be installed as close
to the sample point as possible. Use new tubing in the installation. The
output pressure of the regulator should be 30 psig, whenever possible, to
match the settings of other regulators on the support gas tanks; sample
inlet pressure must exceed the operating sample pressure by at least 10
psig and provide at least 1 SCFH bypass flow. In any case, the zero and
span gas regulators should be set to match the sample pressure
regulator—as the back-pressure regulator within the analyzer ultimately
determines the sample flow to the detection cell. Refer to Chapter 4:
Sampling.
3.3.5.2 E FFLUENT
All the gases introduced into the detection cell vent from one fitting
at the rear of the analyzer. TAI recommends that the cell be permitted to
vent directly to the atmosphere wherever possible.
If a vent line is required, the installation must include a drop-out pot
to collect the water that is formed by the burning of the hydrogen fuel.
The vent line must be constructed so that water and dirt cannot collect in
it.
3.3.5.3 S AMPLE B YPASS V ENT
The sample bypassed by the back-pressure regulation system vents
from a separate port at the rear of the analyzer. If a vent line is required,
it must be installed so that water and dirt cannot accumulate in it.
3.3.5.4 F UEL AND A IR C ONNECTIONS
The fuel used to provide combustion should be a gas mixture
comprised of 40% H
2
and 60% N
2
. The fuel is mixed with air to provide
a combustion source for the analyzer. Connect the fuel and air sources to