Laser beta lasermike LS8000-3 - Manual (Page 19)

LaserSpeed 8000-3 Instruction Handbook
Installing the System
Part No. 93463 / Drawing No. 0921-01561 Page 19 of 221 Revision A (Sep 2007)
for more details. When mounting the gauge, be aware of the environment in
which the gauge is operating. Steam, mist, coolant on the material, ambient
temperature, scale and slag may all affect the performance of the gauge.
These environmental conditions may need to be modified as mentioned above
in order to maximize the performance of the gauge.
Mounting Location
When mounting the gauge over the
material, be sure the gauge is not
directly over a roller or some other
device. If the laser beam from the gauge
strikes an object, it may detect a false
Material Present. In this case, the gauge
will not be able to detect when the
actual material is not in the
measurement volume.
A device that captures most of the laser
light is called a beam dump and may be
required (see figure). A suitable beam
dump is a large-diameter pipe, 150
millimeters (6 inches) or larger, angled
at 45° from the laser beams. A rusty
pipe is an excellent beam dump. If scale
can deposit in the base of the beam
dump, the pipe may need to be cleaned
periodically to prevent false Material
Present readings. The beam dump
should be far enough from the gauge
that it cannot be measured. A good guideline is to place the beam dump at
least double the standoff distance from the gauge. PASSLINE
Standoff
Distance
Rollers
Standoff
Distance
Cut at 45 º
Beam Dump
Open Both Ends