September 2007
2
HygroTrace Moisture Transmitter
Sample System Guidelines (cont.)
•
A sample system should be kept very simple. It should
contain as few components as possible and all or most of
those components should be located downstream of the
measurement location.
•
Sample system components should not be made of material
that will affect measurement. Most common filters and
pressure regulators are not suitable for sample systems
because they have wetted parts that may adsorb or release
moisture, etc. into the sample system. They may also allow
ambient contamination to enter the sample system. If
possible, use stainless steel material for all wetted parts.
•
The transmitter should be installed perpendicular to the
sample inlet. For dimensions and other requirements see
Specifications
on page 26.
Note:
A typical sample system for the hygrometer will use VCR
components.
Note:
At least 5 feet of 1/4” tubing, if vented to the atmosphere,
should be installed on the outlet to prevent back diffusion
of ambient moisture into the sample tee cell of the
HygroTrace
.
•
Sample systems should be leak-tested prior to operation to
verify the integrity of the connections, components and
fittings. Tighten any loose fittings.
IMPORTANT:
Caution must be taken when pressurizing or
depressurizing the sample system to prevent
damage to the moisture sensor.
Figure 1: Sample System Example