Panametrics HydroProII, Руководство пользователя

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Chapter 1. Installation
2 HygroPro
II
User's Manual
1.2 Sample System Guidelines
The HygroPro
II
transmitter can be installed in a sample system or directly in the process line. However, Panametrics
recommends that the transmitter be installed in a sample system to protect the sensor probe from potentially
damaging components in the process stream. Figure 2 below shows a typical sample system.
Figure 2: A Typical Sample System
Note: At least 5 ft. (1.5 m) of 1/4” (6 mm) tubing vented to atmosphere will ensure an accurate process sample and
avoid diffusion of ambient air moisture back into the process.
In the sample system shown in Figure 2 on the previous page, fully open Valve 1 and use Valve 2 to regulate the
sample flow for measurements at process system pressure. For measurements at atmospheric pressure, fully open
Valve 2 and use Valve 1 to regulate the sample flow.
Before constructing a sample system, consult a Panametrics application engineer and observe the following
guidelines:
• The sample system should be very simple and should contain as few components as possible. All or most of
those components should be located downstream of the measurement point.
• Sample system components must not affect moisture readings. Most common filters and pressure regulators
are not suitable for sample systems because the wetted parts adsorb moisture or release moisture into the
sample system. They may also allow ambient contamination to enter the sample system. If possible, use
stainless steel for all wetted parts.
• The HygroPro
II
probe should be oriented perpendicular to the sample system inlet. For dimensions and other
sample system requirements, see “Mechanical” on Page 38.
• Sample systems should be tested for leaks prior to operation, using a Snoop leak detector, to verify the integrity
of connections, components and fittings.
IMPORTANT: When pressurizing or depressurizing the sample system, be careful to avoid shock damage to the
moisture sensor. Also, the sample pressure should be increased/decreased gradually to avoid explosive
decompression of the O-ring.