Second Stage - Tusa RS-340 Manuel D'utilisateur

Regulators
ond stages.The balanced diaphragm method first stage features minimum variation
in intermediate pressure in response to changes in residual cylinder pressure and
depth. The ports are in left-right symmetry (H.P. × 2, L.P. × 4) for easier attachment
to tanks, even for beginners.
R-700 first Stage
The R-700 is a balanced diaphragm first stage with key design and performance
characteristics:
1) Four intermediate pressure ports and two high pressure ports, 2) Balanced first
stage, with a built-in antifreeze system, 3) Replaceable HP seat and HP poppet for
durability and servicing, 4) Two special high flow LP ports (HFP) close to the dia-
phragm offer approximately 15% greater air flow, 5) Dry balance chamber prevents
water contact with the diaphragm and the spring for superior cold water perfor-
mance. The R-700 meets the European Standards EN250:2000 requirements for
cold water conditions.
GB
R-800 first Stage
The R-800 is a balanced piston type first stage offering superior reliability for stable
air supply regardless of depth or residual pressure. It is equipped with four interme-
diate low pressure ports and two high pressure ports.

2.2 SECOND STAGE

Demand system
* The demand system is designed to significantly reduce rubbing resistance of mov-
ing parts and air resistance. The result is smoother and more natural valve opening/
closing.
Light weight housing
* The second stage main unit is smaller and lighter to reduce water resistance dur-
ing diving, thus reducing the load on the face during use. The main body materials
are super-tough nylon (heat pliable polyamide resin) reinforced with glass fiber for
outstanding hardness and shock resistance. The materials also offer superior tensile
strength, dimensional stability, heat resistance, weather resistance and chemical re-
sistance.
Intake resistance
* The second stage includes a director to forcibly guide air from the demand valve.
That prevents free flow while significantly lessening intake resistance. The result is
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