User guide

Getting Started 11

The input and output connectors are clearly

labeled on the Sample Gas section of the back

panel. Depending on the specific model and

ordered options, the stainless steel gas input

and output connections may be 6 mm

Swagelok, ¼ inch Swagelok, or ¼ inch Cajon

VCR.

Note that you should never attempt to measure

any gas with a dew point temperature that is at

or above the temperature of the room. If you

do, condensation will form inside the tubing.

[For

high dew point measurements, a Model 373H or 373HX with

heated internal components and heated hoses is required.]

Swagelok

Tube Fittings

Swagelok® brand tube fittings are generally used to connect the gas inlet and outlet tubes to the

973 system. Depending on the configuration of your specific 973, the back panel fittings are

either ¼” or 6 mm. When ordering tube fittings from your local Swagelok® supplier, be sure to

specify the correct size for your instrument. Swagelok® tube fittings come to you completely

assembled, finger-tight and ready for immediate use. Disassembly before use is unnecessary and

can result in dirt or foreign material getting into the fitting and causing leaks.

SWAGELOK® Tube Fittings are installed in three (3) easy steps:

Simply insert the tubing into the SWAGELOK

Tube Fitting.

Make sure that the tubing rests firmly on the shoulder of

the fitting and that the nut is finger-tight.

Before tightening the SWAGELOK

nut, scribe the nut at the 6

o’clock position.

Hold the fitting body steady with a backup wrench and tighten

the nut 1-1/4 turns.c Watch the scribe mark, make one

complete revolution and continue to the 9 o’clock position.

By scribing the nut at the 6 o’clock position as it appears to you,

there will be no doubt as to the starting position. When the nut is

tightened 1-1/4 turns to the 9 o’clock position, you can easily

see that the fitting has been properly tightened.

Use of a Swagelok

Gap Inspection Gage (1-1/4 turns from

finger-tight) ensures sufficient pull-up.

For 1/16“, 1/8“, 2 mm, 3 mm and 4 mm size tube fittings, only ¾ turn from finger-tight is necessary.