Sea-Bird Electronics SBE 45 MicroTSG, User Manual, Page: 52 / 143

Appendix II: Electronics Disassembly/Reassembly SBE 45
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Appendix II:
Electronics Disassembly/Reassembly
Do not disassemble the MicroTSG electronics unless:
•
moving the J1 jumper on the PCB to change operation from Autopower
(default) to Normal, or vice versa, or
•
troubleshooting a problem, requiring access to the PCB or sensors
Disassembly
1. Remove the six
1
/
4
-inch socket head screws, lock washers, and flat
washers securing the top plate to the housing body. Do not remove the
two screws that are recessed in the top plate – these secure the
electronics to the top plate
.
2.
Remove the top plate by pulling up on it firmly and steadily. It may be
necessary to
slightly twist the top plate back and forth to loosen the o-ring
seals. Lift the top plate vertically off the housing body, being careful not
to hit the conductivity cell on the housing body.
3.
Remove any water from the O-ring mating surfaces on the top plate
assembly and on the housing with a lint-free cloth or tissue.
4.
If applicable, verify/change J1 jumper setting.
Reassembly
1. Remove any water from the O-rings and mating surfaces with a lint-free
cloth or tissue. Inspect the O-rings and mating surfaces for dirt, nicks, and
cuts. Clean as necessary. Apply a light coat of O-ring lubricant (Parker
Super O Lube) to O-rings and mating surfaces.
2.
Align the top plate with the housing body, with the conductivity cell’s
round end cap aligned with the round opening in the housing body.
Slowly lower the top plate, checking that it remains aligned with the
housing body. You will feel resistance as the O-rings on the sensor end
cap enter the housing.
3. Re-secure the top plate to the housing body with the six 1 /
4
-inch socket
head screws, lock washers, and flat washers.
Note:
Before delivery, a desiccant package
is placed in the electronic chamber,
and the chamber is filled with dry
Argon gas. These measures help
prevent condensation. To ensure
proper functioning:
1. Install a new desiccant bag each
time you open the housing. If a
new bag is not available, see
Application Note 71: Desiccant
Use and Regeneration (drying)
.
2. If possible, dry gas backfill each
time you open the housing. If you
cannot, wait at least 24 hours
before redeploying, to allow the
desiccant to remove any moisture.
Note:
Do not disassemble the MicroTSG
to send the sensors or PCB to
Sea-Bird for recalibration or repair
.
Package the entire MicroTSG for
shipment, after removing the
AF24173 Anti-Foulant Device
(see
Section 6: Routine Maintenance
and Calibration ).
CAUTION:
Avoid getting anything on the
PCB
, which can be damaged by
water or other materials.
Pin position on J1:
•
Autopower (default) –
pins 1 and 2
•
Normal –
pins 2 and 3
J1
1
2
3
PCB (labeled 10235)
Screw (typical, 6 places)
Do not remove
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