Checks And Adjustments; Circular Level - Topcon DL-501 Instruction Manual

21.CHECKS AND ADJUSTMENTS

DL is a precision instrument that requires fine adjustments. It must be inspected and adjusted before
use so that it always performs accurate measurements.
• Always perform checking and adjustment in the proper sequence beginning from "21.1 Circular
Level" to "21.3 Adjusting the Reticle".
• In addition, the instrument should be inspected with special care after it has been stored a long time,
transported, or when it may have been damaged by a strong shock.
• Make sure the instrument is securely set up and stable before performing checks and adjustments..
21.1

Circular Level

Check and adjust it as outlined below.

• Be careful that the tightening tension is identical for all the adjusting screws.
• Also, do not over-tighten the adjusting screws as this may damage the circular level.
PROCEDURE Checking and adjusting
1. Adjust the leveling foot screws until the bubble
is centered in the circle.

"6.2 Leveling steps 3 to 5"
2. Turn the instrument 180°. The bubble should
not shift from the center. If the bubble does
move, adjust as follows.
3. Compensate for one-half of the shift by
adjusting the leveling foot screws.
4. Eliminate the remaining shift by turning the
circular level adjusting screws with the
hexagonal wrench until the bubble is centered.
5. Turn the instrument 180°. If the bubble stays in
the center, adjustment is complete. If the
bubble moves, repeat steps 3 and 4.
1/2
Adjust with
hexagonal
wrench
1/2
105