User manual
Poseidon MKVI User Manual
Chapter 1
Page 10
Figure 1-12. How the rig should appear when properly assembled.
Diluent cylinder
Cylinders and regulators
The Poseidon MKVI (EU version only) is factory-issued with two 3-liter aluminum cylinders with
Poseidon post-style valves (see Figure 1-12). The oxygen cylinder has a white valve knob and
the diluent cylinder has a black valve knob. Both cylinders are pressure-rated to 204 bar /
3000 psi service pressure. However, the specied maximum safe FILL pressure for the oxygen
cylinder is 135 bar / 2000 psi. The reason is twofold: rst, the risk of oxygen re increases
sharply at higher pressures; and second, using a greater supply of oxygen increases the risk
that the CO
2
absorbent cartridge may not be sufcient to last for the entire dive on a single ll.
It is also extremely important to NOT replace either of regulators that are provided with the
Poseidon MKVI. The oxygen cylinder, valve, and regulator have been cleaned for oxygen
service at the rated cylinder pressure; using regulators or valves not so cleaned dramatically
increases the risk of oxygen re and/or explosion. More importantly, the provided regulators
have been adjusted with a lower interstage pressure for use with the oxygen and diluent
solenoid valves. Using different regulators with higher interstage pressures will cause the
solenoid valves to fail, and may lead to permanent damage.
DANGER:
Do not ll the oxygen cylinder to more than 135 bar (2000 psi).
Doing so may allow a diver to exceed the duration of the absorbent
cartridge, which could lead to dangerously elevated CO
2
levels in
the breathing mixture.
DANGER:
Only use the rst-stage regulators provided with the Poseidon
MKVI. Not only do the provided regulators have specic features
required by this application (e.g. integrated over-pressure relief
valves, oxygen regulator cleaned for oxygen service), but the
interstage pressure of these regulators is adjusted for use with the
solenoid valves. Use of different rst-stage regulators can lead to
solenoid failure (thereby disabling gas control), and can also lead
to PERMANENT damage to the solenoid valves.
Oxygen cylinder