Appendix Afaq(T)'S - POSEIDON Xstream Series Service Manual

SERviCE maNual - xSTREam aPPENDix a
APPENDIX A
FAQ(T)'s
What shall be used, viton or nitrile?
In short, viton is less likely to ignite but if it does the fumes are extremely toxic. Nitrile is more likely to ignite and releases more
heat energy than viton, but the fumes are less toxic. Nitrile has normally better mechanical properties, i.e. it is a better and more
reliable seal. Therefore, the risk for, and the consequences of either a failure because of ignition or a loss of seal, determines
whether viton or nitrile shall be used.
What about the 40% rule?
In the past some claimed that using gasses containing les than 40% oxygen did not require any special procedures such as e.g.
oxygen cleaning. Since it is only a matter of what level of risk that can be accepted, and Poseidon's standpoint is to lower the
risk as far as possible for our customers safety,
Xstream Deep 90 regulators and 1st stages with serial number 1500001 and higher are delivered "Nitrox Ready" from the fac-
tory. It means that all o-rings are approved for use with enriched gas according to EAN40 and only oxygen compatible lubrica-
tion is used. To keep the regulator "Nitrox Ready", a EAN40 service kit must be used and cleaning and lubrication instructions
in this service manual must be followed.
Older Xstream Deep regulators and 1st stages can be cleaned to achieve "Nitros Ready" status using the EAN40 service kit
and EAN40 service instructions in this service manual.
Upstream valve and sieze of gas?
The servo valve of the Xstream (and Jetstream) is an upstream opening valve. Because of its small size, an extremely small
force is required to crack it open and thereby allow the main valve to open. Even if there is a first stage failure increasing the
Interstage pressure, the Interstage pressure will never be greater than twice the originally set IP because of the OPV. In this
situation, the cracking pressure will be doubled, but still very small why the regulator will work normally.
Unadjustable, will it keep its setting?
Spontaneous alteration of setting is most commonly due to fatigue of springs. Significant fatigue only occur if the spring is
stressed beyond its plastic deformation threshold. A correctly chosen spring will therefore not fatigue and keep its setting.
Can I use Christo-lube instead?
As per 31/1 2003 Christo-Lube 111 is approved for use with 100% oxygen to 110 bar at 60°C, which is less than the maximum
working pressure of Xstream Deco and can therefore not be used. Poseidon 1 Grease is approved for100% oxygen to 270 bar
at 100°C.
Can I put a jetstream 2 stage on an Xstream 1 stage?
nd st
Yes.
Can I put a Cyklon 5000 2 nd stage on an Xstream 1 st stage?
This combination is not CE-approved. The Cyklon 5000 2 stage require an IP at 11.5 bar which can only be set with a Xstream
nd
1 stage that has an adjustment screw.
st
What is the expected service life of the servo valve?
If handled in accordance with the instructions given in the users manual, it is not something that should be expected to need any
replacement. The most common problem is ingress of water due to immersion of an unpressurised regulator. In such case, salt
crystals can form inside the servo valve and create a minor leakage.
Why do Poseidon refer to NORSOk U-101 TBD?
NORSOK U-101 is a Norwegian off-shore standard for testing diving equipment's performance down to 400m (1312 ft) depth.
Its requirements put greater demands on breathing resistance than EN 250 does.
Why isn't Xstream marked EN 250?
EN 250 requires a limitation in use to maximum 50m depth. Xstream is tested and fulfil all requirements of the EN 250, except
for it is not limited to 50m, but to 200m depth
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