Topcon GLS-1000 SERIES, Instruction Manual

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4-2
4 PREPARATION FOR MEASUREMENT
4.2 Mount the Instrument to the Tripod
First, mount the tribrach to the tripod. Roughly level and center the tribrach.
Next, mount the instrument to the tribrach. Level and center the instrument precisely.
Level and center the instrument precisely to insure the best performance.
Use tripods with a tripod screw of 5/8 in. diameter and 11 threads per inch, such as the Type E
TOPCON wide-frame wooden tripod. Do not use a metallic tripod.
4.2.1 Leveling and Centering the Instrument
1
Setting up the Tripod
1) First, extend the extension legs to suitable lengths and tighten the screws on their midsections.
2) Remove the tribrach from the instrument, and place the tribrach carefully on the tripod head.
3) Loosen the tripod screw and slide the instrument. When the instrument is directly above the point,
lightly tighten the tripod screw.
2
Roughly Leveling the Tribrach by Using the Tribrach circular level
1) Turn the leveling screws A and B and adjust the bubble to stay at the top or bottom of the circular
level.
2) Turn the leveling screw C to bring the bubble to the center of the tribrach circular level.
3
Centering by Using the Optical Plummet Telescope
1) Adjust the eyepiece of the optical plummet telescope to your eyesight.
2) Slide the instrument by loosening the tripod screw, place the point on the center mark, and then
tighten the tripod screw.
Try to keep the tribrach from rotating when sliding it so as to minimize the dislocation of the bubble.
3) Repeat step 2 and 3 if necessary.
Leveling
screw A
Leveling screw C
Leveling screw B
Tribrach circular level
Point
Center mark