TM 5-6675-328-14
2-20.4 Remove/Install Optical Plummet Collimator Assembly.
MOS: 41B, Topographic Instrument Repair Specialist
TOOLS: Hex Head Key Wrench Set
Spanner Wrench
SUPPLIES: Optical Plummet Collimator
WARNING
Death or serious injury from electrical shock may occur unless power cord is unplugged
before servicing equipment.
a. Unplug power cord.
b. Remove the OPC Assembly as follows.
WARNING
Keep test post locked. Test post may drop if left unlocked. To avoid personal injury, keep
hands and body from under test post.
(1) Remove motors in accordance with paragraph 2-20.3.
(2) Unscrew lighting unit from OPC.
(3) Mark the exact orientation of the plummet adapter tube with relation to the bottom of the test post.
(4) Loosen lock ring securing the plummet adapter tube to the test post and unscrew the plummet adapter
tube completely.
(5) Remove eight hex head screws holding motor mounting bracket to the bottom of the plummet tube and
remove motor mounting bracket.
c. Install the OPC Assembly as follows.
(1) Install the motor mounting bracket and secure with eight hex head screws.
(2) Screw the plummet adapter tube into the test post.
(3) Match up the marks that were made during removal and tighten the locking ring.
(4) Install the motors in accordance with paragraph 2-20.3.
(5) Screw the lighting unit into the OPC.
(6) Close the cabinet door.
(7) Plug in power cord.
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