3.2
Checking the line of
sight
Adjusting the line of
sight
NA320/24/32, Operation
Check & Adjust the line of sight
Step
Description
With the circular bubble centred and
adjusted, the line of sight should be
horizontal.
1.
Choose a distance of appr. 30 m within
a gentle terrain.
2.
Set up a staff at both final points (A,
B).
3.
Set up the instrument at point I
(halfway between A and B, just pass it
down) and centre the bubble.
4.
Read both staffs.
Reading on A = 1.832 m
Reading on B = 1.616 m
ΔH = A - B = 0.216 m
5.
Set up the level about 1 m from staff A.
6.
Read staff A (eg.: 1.604 m).
7.
Find nominal reading B; eg.:
Reading A - ΔH = 1.604 m - 0.216 m =
1.388 m.
8.
Read staff B, compare nominal-/actual-
reading.
Step
Description
When the difference nominal-/actual- reading is
more than 3 mm the line of sight must be adjusted.
1.
Turn the adjusting screw until the middle hair gives
the required reading (eg. 1.388 m).
2.
Check line of sight again.
Before starting field work or after long periods of
storage/ transport of your equipment check the field
adjustment parameters specified in this User
Manual.
H=1.832
H=1.616
δ
I
1
A
d
003993_001
1
actual = 1.604
nominal
I
2
= 1.388
A
003994_001_en
003995_001
en
δ
B
d
δ
B
10