7.2.5.5 Setting a marker
The surfaces of many structures contain obstacles that make it impossible to record the scan without lifting the
scanner from the surface. Examples of such obstacles are piers or columns on a wall, door openings, expansion joints,
pipes, scaffold bars, corners etc.
If an obstacle is encountered, a marker can be set. This interrupts the scan and allows the user to lift the scanner away
from the surface, place it beyond the obstruction and then continue scanning. It also indicates where certain objects
are located within a scan, providing additional information that creates a reference between the scan data and the
en
actual surface.
To set a marker, press and hold the Confirm button while in recording mode. The diskette symbol will be crossed out,
indicating that recording has been suspended and a marker has been set.
CAUTION
Due to interruption of the recorded signal, scanning results are less accurate immediately before and after the point
where a marker is set.
Do not interrupt the scan at the position of a reinforcing bar.
Then lift the scanner from the surface while keeping the Confirm button pressed. If necessary, mark the position on
the surface using a PUA 70 marking pen. Place the scanner back on the surface beyond the obstacle, release the
Confirm button and continue scanning. The marker will be shown as a vertical line in the scan data when viewed on
the monitor or in the PC application.
7.2.6 Imagescan
Imagescan is used to create an image of the reinforcement layout. The depth and diameter of the bars can be
determined or, respectively, estimated.
A reference grid must first be fixed to the wall. Use the adhesive tape supplied for this purpose. This tape adheres well
to concrete and can be torn off the roll by hand in the lengths required. For most surfaces, a 10 cm length of tape at
each corner is adequate to secure the grid. If the concrete surface is very damp or dusty, use the brush supplied to
clean off any dirt and dust. The reference grid may then have to be attached by applying a strip of tape along the full
length of each edge.
Alternatively, a grid can be marked directly on the surface. Using a straight edge (such as a piece of wood) as a guide,
mark out a 4 x 4 grid with the parallel lines spaced at intervals of 150 mm. The holes punched in the paper reference
grid can also be used to mark the positions of the grid lines on the concrete surface.
Switch the scanner on and select the Imagescan symbol. The battery level is displayed together with the number of
Imagescans currently held in memory (a maximum of 9).
Select Imagescan from the main menu.
The Imagescan screen is displayed.
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