Manual rEvo III
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2.2 Counterlungs:
The rEvo counterlungs are made of food-compatible PU, sealed with high frequency
welding technology and are permanently elastic. Both counter lungs (inhale and
exhale) are backmounted. Both lungs are protected by a liner and are fitted in a
stainless steel case. This case is produced in such a way it perfectly fits the back of
the diver.
The placement of the counter lungs provide the diver a clear chest-area. The lungs do
not limit the movement or the vision of the diver. That way it is easy to work with
stages. The case provides excellent lung-protection in hazardous environments like
wrecks or caves.
The hoses for manual addition of oxygen and diluent are fed into the exhale lung. The
ADV and orifice are also situated in the exhale lung.
The exhale and inhale lung are connected by two serially placed scrubber canisters.
Both canisters are thermally isolated by an additional air chamber. The oxygen cells
are located beneath the canister in the inhale lung. The flow of the warm gasses in
the breathing loop, coming from the second canister, keep the cells dry. An anti-
collapse hose is mounted in the inhale lung.
An “over pressure valve (OPV)” is mounted on top of the unit, on the exhale side. The
cable entry port is mounted on the inhale lung side.
2.3 ADV:
The “auto-diluent-valve (ADV)” is activated by the pressure created when the exhale
lung ‘bottoms out’ (for example during descent). Diluent is injected into the exhale
lung. Access to the ADV is possible for breathing resistance adjustment (when
necessary).
See photograph below(2.4 orifice)
2.4 Orifice:
To guarantee a constant oxygen flow, an orifice is used. This orifice (a small opening
situated in the oxygen hose allowing oxygen flowing through) gives, at a fixed inlet
pressure, a constant oxygen inflow, independent of the outlet pressure. (Within the
manufacturer’s limits of use of the rEvo).
The result is a constant flow even when the depth increases. To keep the inlet
pressure fixed, a special first stage regulator is used.
