Sea-Bird Scientific SBE 37-SM Product Manual Download Page 63

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Manual revision 041

Section 5: Routine Maintenance and Calibration

SBE 37-SM RS-232

Handling Instructions for Plastic ShallowCAT

The MicroCAT’s 7000-meter titanium housing offers the best durability with a
modest amount of care. The

ShallowCAT

, a 350-meter plastic housing, saves

money and weight. However, more care and caution in handling is required.
To get the same excellent performance and longevity for the plastic-housing
version:



The MicroCAT’s connector end cap is retained by two screws through the
side of the housing. The screw holes are close to the end of the housing.
Particularly in a cold environment, where plastic is more brittle, the
potential for developing a crack around the screw hole(s) is greater for the
plastic housing than for the titanium housing. Observe the following
precautions –



When removing the end cap (to replace the AA cells and/or access
the electronics), be careful to avoid any impact in this area of
the housing.



When reinstalling the end cap, do not use excess torque on the
screws. Sea-Bird recommends tightening the screws to 15 inch-lbs.
Alternatively, tighten the screws finger-tight, and then turn each
screw an additional 45 degrees.



A plastic housing is more susceptible to scratches than a titanium housing.
Do not use screwdrivers or other metal tools to pry off the end cap.



Of primary concern are scratches on O-ring mating and sealing
surfaces. Take extra precaution to avoid a scraping contact with these
surfaces when replacing AA cells and/or re-seating the end cap.



Also take care to keep the O-ring lubricated surfaces clean – avoid
trapping any sand or fine grit that can scratch the critical sealing
surfaces. If the O-ring lubricant does accumulate any material or grit
that can cause a leak or make a scratch, it must be carefully cleaned
and replaced with fresh, clean lubricant (Parker Super O Lube).



Shallow, external scratches are cosmetic only, and will not affect the
performance of the MicroCAT. However, deep external scratches can
become points of weakness for deep deployments or fracture from
impact during very cold weather.



If you remove the screws securing the conductivity cell guard to the
housing (not typically done by the customer), follow the same precautions
as described above for removing and replacing the connector end cap.

See

Battery Pack Installation

Section 3: Preparing MicroCAT for

Deployment

and

Appendix II: Electronics Disassembly / Reassembly

for

detailed step-by-step procedures for removing the MicroCAT’s end cap.

Replacing AA Cells

Remove the 2 cap screws holding the I/O connector end cap to the
MicroCAT housing. Remove the end cap by twisting the end cap counter
clockwise; the end cap will release from the housing. Pull the end cap out.

Loosen the captured screw holding the battery pack in the housing, and
remove the battery pack from the housing.

Place the handle in an upright position. Unscrew the

yellow

cover plate

from the top of the battery pack assembly.

Roll the 2 O-rings on the outside of the pack out of their grooves.

Remove the existing cells. Install new cells,

alternating

positive (+) end

first and negative (-) end first to match the labels on the pack.

Roll the O-rings into place in the grooves on the side of the battery pack.

Place the handle in an upright position. Reinstall the battery pack
cover plate.