150-506-100-03
Overview
HRE-506 List 1 and List 2
March 28, 2000
3
An optional breather vent assembly is enclosed in the air-filled HRE-506 List 2 shipping kit. The kit is a small
plastic bag attached to a red and brown colored spare pairs shrink tube. The breather vent replaces the
pressure-relief valve, if the air-filled unit is not pressurized. The assembly allows the enclosure to breathe and
keeps the internal atmosphere free of harmful contaminants.
shows the five metal valves.
Figure 2.
Metal Valves
Unlike the gel-filled unit, the pressure cutoff valve in the air-filled unit cannot be used to
cut off an external air source that is applied to the Schrader air stem valve. The air-filled
unit pressure cutoff valve can only control the air source that is applied to the enclosure
through the air core stub.