ADC 150-2202-01, Руководство пользователя

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Appendix A - Technical Reference 150-504-100-03
26 August 1, 2002 HRE-504 List 1, List 1B, and List 2
Vented-to-Pressurized Conversion Procedure
The following instructions are for converting the HRE-504 List 1 gel-filled vented enclosure to an external
pressurized enclosure.
The HRE-504 List 1 enclosure can be converted to a pressurized housing that uses a continuous, local air pressure
source. The conversion requires replacing the breather vent valve with an optional pressure relief valve. The
breather vent assembly, located in the base pan, allows the internal pressure to equalize with the outside pressure.
The optional pressure relief valve, included in the shipping kit, replaces the breather vent valve and prevents
over- pressurization when pressurizing from an external air source. The HRE504 List 1 has a gel-filled cable,
which precludes pressurizing through the cable stub.
Use the following instructions to convert the HRE 5-4 List 1 enclosure from a vented to pressurized housing:
1 Locate the breather vent valve on the bottom of the housing. It is a metal valve located adjacent to the cable
stub inlet, as shown in
Figure 2 on page 3 .
2 Remove the valve by untightening it in a counterclockwise direction.
3 Save the vent or store it inside the housing for future conversions.
4 Check the threaded hole for debris and clean it, if necessary.
5 Remove the pressure relief valve from the plastic bag. Verify that an O-ring is installed on the threaded end
of the valve.
6 Carefully place the threaded end of the air pressure cutoff valve into the threaded brass fitting where the
breather vent assembly was removed.
7 Hold the valve straight and push it into the hole. Turn the valve clockwise to tighten it in place.
8 Handtighten the valve until it is tight against the gasket material.
The housing is now ready to be pressurized either through the T-valve’s Schrader air stem, which accepts a
standard tire valve chuck, or the external air intake stem of the T-valve, as shown in
Figure 3 on page 5 . A
desiccant bag is also included in the HRE-504 List 1 shipping kit with the pressure relief valve. Remove this bag
and place it in the HRE-504 prior to pressurization.
To pressurize the enclosure:
1 Attach a plastic tube,
1
/
4
-inch (.64 cm) inner diameter (ID) by
3
/
8
-inch (.83 cm) outer diameter (OD) from the
external air source to the
1
/
4
-inch (.64 cm) air intake protrusion of the T-valve. The plastic tube is not included
in the kit.
2 Secure the plastic tube to the valve with the hex bolt and ferrule.
Static pressurization requires monitoring and maintenance as the pressure decreases over
time.
If there are any signs of resistance while tightening the valve, you could be cross-threading
the part. Remove the valve and restart.
The plastic tube and fitting assembly is also called an Express Air Connection Fitting. These
parts are not supplied by ADC.