POSEIDON SE7EN+ - Invalid Cylinder Pressure; Chapter 3 Page 59

Poseidon SE7EN+ User Manual Chapter 3 Page 59
The high pressure sensor signals are continously monitored to detect if the signal falls out of
the valid range or if the signal increases unexpectedly. A signal below the valid range may be
caused by a cable failure and a signal that increases unexpectedly may be caused by moisture
and / or corrosion inside the cable connector.
An invalid sensor signal means that the measured cylinder pressure is invalid and that the
measured cylinder pressure is regarded as unknown and should not be trusted.
If an invalid cylinder pressure is detected this is indicated on screen with the middle segments
lit for the affected cylinder bar graph. An invalid cylinder pressure further affects the calculated
Remaining Dive Time and other alarms may be triggered since the remaining gas supply is
unknown.
The recommended action when a cylinder pressure is invalid is to abort the dive.
Notice: Normally both cylinder valves shall be opened during the the pre-dive test and remain
in open position throughout the dive until the dive is completed and the rig is powered off.
Closing a cylinder valve during a dive entails the risk of water ingress into the rst stage regula-
tor and from there into the solenoid valves inside the e-module. This might damage the solenoid
valves and require their replacement at Poseidon Head Quarters. Therefore closing the cylinder
valves during a dive is strongly discouraged unless necessary in an emergency situation.
During training of emergency procedures, lower the setpoint to simulate a closed oxygen
cylinder valve. You shall never leave the valves closed, whatever the reason!
Closing a cylinder valve and later opening it can trigger detection of an invalid sensor signal if
the pressure has rst decreased after the valve was closed and then the pressure increased
when the valve was opened. If zero pressure is reached, the invalid sensor status will however
be reset. Remember that the alarm for low cylinder pressure will be active when pressure is
close to zero.
Invalid cylinder pressure
Figure 3-34. Invalid DIL pressure.
Figure 3-35. Invalid O2 pressure.