O P E R AT I N G I N S T R U C T I O N S |
Bulkscan LMS511
8014829/ZNC5/2017-06-06 |
S I C K
Subject to change without notice
5 8
COMMISSIONING
System
tab,
Tolerances
group
8.3.1
Tolerance against vibration
The majority of conveyor belts vibrate in operation as a function of the belt speed and
the load. If the empty conveyor belt vibrates, the conveyor will rise above or drop below
the taught-in reference contour. The Bulkscan would interpret this movement as a
change in the bulk quantity.
For this reason the Bulkscan has a
Tolerance against vibration
that can be configured.
In this case the sensor ignores conveyor belt variations from the bottom edge of the ref-
erence contour and outputs the measured value 0. However this situation also means
that very low bulk quantities are also ignored
How to configure the tolerance against vibration:
Ensure that hazard-free operation is possible and start the empty conveyor belt.
On the
Operating mode
configuration bar, click Measuring mode.
Switch to the System tab.
Reduce the
Tolerance against vibration
so that the
Volume flow rate
measured val-
ue remains constant at 0 with the empty conveyor belt.
Check on the
Measured value
configuration bar whether small bulk quantities are
reliably detected.
8.3.2
Tolerance against reflection
Reflections (total reflection) can result in the Bulkscan measuring the distance to the
reflected object, e.g., a building roof, instead of to the bulk. Examples:
• Fragments of glass as bulk.
• Stagnant water on the conveyor belt.
In this case the distance values measured are way outside the reference area. In rela-
tion to the reference area, the Bulkscan interprets these values as measuring errors:
• The sensor replaces invalid distance values with the last valid distance value.
• The 7-segment display shows
.
•
If you have configured an output as "Information/Warnings", the related output
switches.
You can adjust the tolerance against reflection to suit your application. The value de
-
fines which part of the measured bulk contour must lie outside the sensor-internal dis
-
tance threshold for the contour to be interpreted as a measuring error. A high tolerance
against reflection increases the availability of the sensor.
If you want to detect stagnant water, the value should be low, because the edges of the
conveyor belt that are not covered form part of the contour.
How to configure the tolerance against reflection:
Ensure that hazard-free operation is possible and start the empty conveyor belt.
On the
Operating mode
configuration bar, click
Measuring mode
.
Switch to the
System
tab.
Set the
Tolerance against reflection
to a value of 50%.
Reduce or increase the
Tolerance against reflection
so that the availability of the
system meets your requirements.
8.3.3
Optimization for outdoor applications
Dust particles, rain drops, snow flakes, etc. can block individual measurement points
on the bulk contour. Dazzle from external light sources, such as sunshine or reflections
Recommandation
