HOW TO SET-OUT A SITE
15
Working Example
The following description in this guide, explains the general principles of how to set-out a site
using a rotary laser level like the FRE-205.
Equipment
Outdoors you will need the FRE-205 rotary laser level, a detector (receiver), a surveying tripod
and a measuring staff . However indoors, accessories like wall brackets, interior tripods or fl oor
to ceiling pillar kits are more useful and replace the surveying tripod / staff .
Basic Outdoor Procedure
In a convenient, safe place, position the tripod with its top face generally level (/-5
degrees) and about 1.3m above ground level. This ensures the laser beam is generally below eye
level. Securely attach the FRE-205 via the 5/8” fi xing screw. Press the
ON/OFF
button once and
the FRE-205 will power on and begin automatically self-levelling horizontally. This process takes
around 15-20 seconds. When the levelling process is complete, the laser beam will start spinning
at 600rpm, indicating a level datum. This gives a truly horizontal spinning beam of laser light
across the work-site. A reference DATUM.
The FRE-205 will automatically default to 600RPM. This will give the best range and stability
when using the laser detector.
The laser detector which is also referred to as: a receiver, rod eye, laserometer, scouts, bleepers,
sounders and that “thing you stick on a staff ”, is basically a battery powered device, designed to
fi nd the middle of the laser beam that you cannot see outdoors, by eye.
Loosely attach the detector to the measuring staff via its bracket, so that the pick-up window
faces the laser’s beam and the rear of the detector reads the mm scale on the staff . Move the
detector up & down the staff to receive a continuous tone on the sounder and a set-level bar on
the LCD. Clamp it securely in place. (Not over tight).
It is often better to stand behind the staff , to read both the detector’s rear display and the staff s’
mm scale.
Now, if you move to a second site position and the detector gives the same level signal (with a
continuous tone) then you know that the base of the staff is LEVEL with the initial position. Any
deviation can be measured by un-clamping the detector and moving it up or down the staff to
fi nd the laser beam again, noting the change in vertical distance on the staff .
This technique can be used for laying concrete bases, pads or strip foundations etc.
