Description And Operation; General; First Stage - Tusa RS-340 Manual Del Propietário

Regulators
SECTION II

DESCRIPTION AND OPERATION

2.0 GENERAL

TUSA Regulators are BALANCED PISTON and BALANCED DIAPHRAGM type SIN-
GLE HOSE REGULATORS. The regulator reduces high pressure air from the scuba
cylinder to ambient pressure suitable for breathing, through the operation of fi rst and
second stage regulators. The fi rst stage regulator reduces incoming high pressure
air, to an intermediate pressure of approximately 135PSI ( 9.5bar). The second
stage regulator, using a diaphragm operated demand valve, further reduces air from
intermediate pressure to ambient pressure permitting normal breathing. The fi rst and
second stages of the regulator are connected by a low pressure hose. A swivel yoke
(TYPE INT) on the fi rst stage body secures the regulator to the cylinder valve, while
an O-ring surrounding the outlet orifi ce on the cylinder valve ensures an airtight con-
nection to the fi rst stage.
GB

2.1 FIRST STAGE

R-300 fi rst stage
In order to achieve natural breathing, a dynamic fl ow hose with a large inner diam-
eter increases the airfl ow. The R-300 always supplies the diver with stable air at any
tank pressure or depth, delivering maximum breathing ease and comfort for them.
R-400 fi rst Stage
The TUSA R-400 offers a first stage with the balanced diapraghm method. This
method features minimum variation in intermediate pressure in response to changes
in residual cylinder pressure and depth. The R-400 is engineerd for cold water diving
(EN-250-2000). It also offfers two high high fl ow LP ports (HFP) that are close to the
diapraghm to increas the airfl ow by aproximately 15%.
R-500 fi rst stage
The very popular balanced piston type fi rst stage offers superior reliability for stable
air supply regardless of depth or residual pressure.
R-600 and R-600 DRY fi rst stage
With the R-600, offers a compact design weight of just 630g during actual use.
This allows the R-670 to only be a total weight of just 1050g for the fi rst and second
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