User manual

Poseidon MKVI User Manual
Chapter 1
Page 22
Figure 1-30. Align the cable junction box with the
front of the gas processor (closest to backpack),
then insert the electronics module innto the
processor housing
Inspect the inner and outer radial sealing surfaces in the electronics module receiver pocket at
the top of the gas processor (see Figure1-30). These surfaces should be free from scratches,
gouges, and dings. Ensure that these surfaces have a smooth application of lubricant and that
no debris, dust or other foreign material is present.
Inspect both inner and outer electronics module radial o-rings (Figure 1-30). If any of the
o-rings are damaged, cut, or gouged, replace them. Ensure that each o-ring is lubricated and
that there is no debris, dust, sand etc. on any of the o-rings.
Orient the electronics module such that the cable entry port is aligned towards the front of the
gas processor, as shown in Figure 1-30, and carefully press the electronics module into the
receiver pocket in the top of the gas processor housing as shown in Figure 1-30.
Be sure when inserting the electronics module into the open receiver cavity at the top of the
gas processor that the radial o-rings do not extrude from their circular grooves. The radial
o-rings in the electronics module should insert smoothly into the gas processor receiver cavity
until they are no longer visible and the under-side lip of the electronics module fastener hand
nut ange is ush with the top ledge of the gas processor receiver cavity. (see Figures 1-30 and
1-31 for proper seating of the electronics module).
Tighten the left and right retainer hand nuts as shown in Figure 1-31. Do NOT use tools or you
may strip the threads. Great force is not required to seal the module.
Figure 1-31. Firmly screw down the
hand nut on the right and the left side
of the electronics housing (use NO
tools)
WARNING:
Deep, permanent scratches, cuts, gouges or other damage to the
polished radial sealing surfaces of the electronics module, and/or
failure to ensure that all electronics module o-rings are in place,
free of debris, and are lubricated, could lead to water entry into
the top of the cartridge housing during a dive, eventually causing
a lock-up of the breathing loop and forcing an immediate open-
circuit abort to the surface.
DANGER:
The electronics module contains the most important life-critical
element of the Poseidon MKVI: the oxygen sensors. A leak into
the electronics housing may contaminate the oxygen sensors
and prevent them from providing correct readings. Dual radial
o-rings help to guard against this, and the computer system is
programmed to discover anomalies in the oxygen sensors and
to attempt to repair the situation. Detection of an oxygen sensor
anomaly will lead the computer to advise an immediate abort to
the surface in open-circuit mode. Always pay particular attention
to the instructions regarding o-ring installation and o-ring surface
inspection.
Outer radial seal
Inner radial seal
Outer radial
sealing surface
Inner radial
sealing surface