Kapro PROLASER ALL-LINES 875 GREEN Manuel D'utilisation page 25

14) Mark point a2 on wall A, in the middle of the side vertical
beam, near point a1 and at the same height.
(see figure #13).
X
d1
15) Measure the distances:
16) The difference Δ from a1 to a2 should be no more than 3 mm,
if otherwise, send the laser level to a qualified technician for
repair.
17) Repeat the same procedure (1 – 16) to check the perpendicularity
between the other 2 vertical beams.
D
Figure # 13
Figure # 13
Δ = from a1 to a2
A
a1 X a2
X
X
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