Multi-Pointer
Service Manual
Page 18 of 26
7 Accuracy Check and Adjustment
7.1
Set up the reference
Fig. 23
1. Show as Fig. 23, Put a flat stand 5m away from the three-side walls respectively. The stand is about 1m high.
2. Put a bracket with a hole in the center on the stand.
3. Draw a 3mm hole on one right-angle surface of the prism. Put the prism below the bracket and on the flat. The
hole on the right-angle surface must be on one line with the bracket center hole. Adjust the angle to make the
down beam emitted by the instrument be reflected on the wall near the position P;
4. Prop up the theodolite above the bracket using a tripod. The theodolite down laser point be on one line with the
center of the 3mm circle (under-mentioned as down point near the light)
5. Use the theodolite to line out three vertical lines on the wall respectively. All angle between the three vertical
lines are right angle.
6. Put a high-accuracy instrument on the bracket. Turn on the instrument to make the front laser point project on
the wall. Use the optic level and the ruler near the light to line out three horizontal lines having the same height
on the wall.
7. Mark the three cross points of the three vertical lines and the three horizontal lines A
,
B
,
C, which is the left, face
and right spot as the reference point.
8. Take a high-accuracy instrument and make its down point be on one line with the down point near the light.
Then put a right-angle prism on the bracket. Adjust the angle to make the up laser point emitted by the
instrument be reflected on the wall near the position O;
9. Make the front laser point face the wall. Mark the up and down spot reflected through the prism on the wall as O1
and O2. Then rotate the instrument by 90
o
, 180
o
and 270
o
clockwise, and mark O2, O3, O4 and P2, P3, P4;
10. Take the cross point of O1, O2, O3, O4, This cross point just is the reference point for the up laser point. Take
the cross point of P1, P2, P3, P4, This cross point just is the reference point for the down laser point. (See Fig.
24)
Fig. 24
