15
Checking Vertical Accuracy
1. Set up the instrument between 2 walls (or 2 grade rods) about 30m
from each other. Set it closer to one wall than the other as shown
below ( Figure 2 ).
2. Lay down the instrument as shown. Press the Power Button and the
instrument will find its level position. Mark the laser position on the wall
as
hA
and
hB
.
3. Then re-install the unit to close to the other wall as shown below
( Figure 3 ), repeat step 2 and mark the points as
hA1
and
hB1
. Calcu-
late
Δ 1=hA – hB , Δ2= hA1 - hB1.
The difference between
Δ1
and
Δ2
should be within
+/- 1/8in .
Figure 3
Figure 2