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SICK LSI Technical Description - 06/98
Plausibility check
Function of the PLS/LSI user software with which you can check
for errors in the definition of monitoring cases.
Speed difference
In vehicle protection, the speed of two axles - or running wheels
- is recorded by incremental encoders. When the vehicle goes
round a bend these two items of speed information may differ.
In the PLS/LSI user software you can specify how large the
maximum speed difference between the two incremental
encoders may be before the system is shut down (default for
speed difference: 25%).
Space contour
You can receive the defined contour of a sensors surroundings
and save the measurements obtained. In this way, when error
shutdowns occur you can check at which point the space
contour protrudes into the protective field.
Warning field
The warning field is a sensor field with a radius up to 15 metres.
It can be used to monitor larger areas and to trip simple
switching functions (e.g. warning functions) or to switch a
driverless transport system to slow running.
12 Glossary
DTS
Driverless Transport System (industrial conveyors).
Incremental encoder
A component which generates electrical pulses proportional to a
movement. From these pulses various physical variables can be
derived (e.g. speed, distance, etc.).
I/O monitor
Function of the PLS/LSI user software with which the switching
states of the LSI inputs and outputs are monitored and logged.
The data obtained can be saved to an ASCII file for subsequent
evaluation.
Measurement zone
The field of vision of the PLS is its measurement zone. It is
heavily dependent on the remission of the object struck, but
without special measures extends to around 15 metres. When
using heavily reflective materials the maximum range of 50
metres is also achievable.
With the PLS the distance to objects can also be measured in
order to display them on the PC (by way of the computer
interface) or to carry out any other evaluations on a computer.
Monitoring area
A monitoring area consists of a protective field and a warning
field. In the PLS/LSI user software up to eight monitoring areas
can be defined in a configuration, assigned to the connected
sensors according to the monitoring case.
Monitoring case, simultaneous
A maximum of two monitoring cases can be active at any one
time, i.e. under the same input conditions, on a LSI.
Pixel suppression
When you select Pixel suppression, objects detected by just
one pixel per scan are ignored. This can be useful in preventing
error shutdowns.
Protective field
In the range up to a radius of 4 metres, the PLS/LSI system
offers eight sensor fields with single-fault fail-safe accident
prevention functions in accordance with category 3 of
EN 954 - for area protection, but also as a (non-tactile) bumper
replacement.
