Manual revision 001
Section 4: Deploying and Operating SBE 39
plus
-IM
SBE 39
plus
-IM
69
Recovery
1.
Rinse the 39
plus
-IM with fresh water, and dry thoroughly.
2.
If immediate redeployment is not required, it is best to leave the
39
plus
-IM with batteries in place and in a quiescent (sleep) state
(
PwrOff
), so that date and time are retained. Because the quiescent
current required is less than 60 microAmps, the batteries can be left in
place without significant loss of capacity (13% per year).
WARNING!
If the 39plus-IM stops working while
underwater, is unresponsive to
commands, or shows other signs of
flooding or damage, carefully secure
it away from people until you have
determined that abnormal internal
pressure does not exist or has been
relieved.
Pressure housings may flood
under pressure due to dirty or
damaged o-rings, or other failed seals.
When a sealed pressure housing
floods at great depths and is
subsequently raised to the surface,
water may be trapped at the pressure
at which it entered the housing,
presenting a danger if the housing is
opened before relieving the internal
pressure. Instances of such flooding
are rare. However, a housing that
floods at 5000 meters depth holds an
internal pressure of more than
7000 psia, and has the potential to
eject the end cap with lethal force.
A housing that floods at 50 meters
holds an internal pressure of more
than 85 psia; this force could still
cause injury.
If you suspect the 39
plus
-IM is flooded,
point it in a safe direction away from
people. Slowly turn the end cap ¼ turn
at a time (using a wrench on the end
cap’s wrench flats), letting the internal
pressure bleed off slowly past the
o-rings as the o-rings are released from
the housing. Then, you can completely
remove the end cap and electronics
from the housing.
