Operating Instructions
Chapter
3
CLV 480 Bar Code Scanner
8 010 080/O824/10-02-2005
©
SICK AG · Division Auto Ident · Germany · All rights reserved
3-7
Product description
3.2.1
Event-controlled dynamic focus control
The CLV can switch its focus position in response to certain events and thus dynamically
cover a large reading range. A maximum of eight reading ranges can be defined as distance
configurations for this purpose and approached consecutively in reading mode (see
).
The switch over takes place in response to changes in the object distance (with reads from
above: object height detection). The trigger source for the switchover can be:
•
A signal combination at the "IN 0" to "IN 4" switching inputs, a command on the host
interface/terminal interface or the integrated timer (e. g. for search mode). Additional in
the case of the line scanner with oscillating mirror also the oscillating mirror reversal
points. The distance configurations are assigned to the switchover sequence by means
of a programmable assignment table.
•
In combination with the OTS 400 Omni Tracking System:
Alternatively the object height information from the OTS 400 or any other CLV via the
CAN bus.
3.2.2
Reading modes
Start/stop mode
During the reading process, only
one object
is located in the reading field in start/stop
mode, i. e. all read bar codes can be clearly assigned to the object. As default, two reading
pulse sensors at the beginning and at the end of the reading field control the starting and
stopping of the reading process (
). The size of the reading field is determined by the
distance between the two sensors. Alternatively, the reading process can be controlled with
command strings via the data interface or can be left free running. The CLV either outputs
the reading result at the end of the reading pulse (the back edge of the object has left the
end of reading field) or already during the reading pulse as a result of predefined (parame-
trized) conditions. To separate bar codes of the same type with identical contents, an incre-
mental encoder must be connected to the CLV.
Fig. 3-3:
Dynamic focus control: classification of the reading range in distance configurations
1 2 3
5
8
4
6
7
Reading
field height
Focus
position
Reading distance
Focus position
Reading distance
DC = Distance Configuration
DC 1
DC 3
DC 4
DC 6
DC 7
DC 8
DC 2
DC 5
