Barcode reader VB34
Installation
Da
te
of
issue
06/
1
3
/2005
28
Subject to reasonable modifications due to technical advances.
Copyright Fuchs, Printed in Germany
Fuchs Group • Tel.: G49 621 776-0 • USA +1 330 4253555 • Sin65 67799091 • Internet http://www.pepperl-fuchs.com
Figure 6.17
Connection layout of the RS232 interface
Inputs
The inputs of the reader are lead through on the 25-pin or 26-pin connector (Figure
6.11) of the VB34.
The inputs are labelled EXT_TRIG, IN2, IN3 and IN4.
IN2 is normally used as encoder input. In the PackTrack™ operating mode, this input
is used to measure the speed of the band.
EXT_TRIG is the primary presence sensor. An active signal at this input informs the
reader that a code is to be read and decoded. A (yellow) LED indicates that the
EXT_TRIG signal is active.
IN3 and IN4 can be used as stop signal for the read cycle.
All inputs are galvanically isolated by means of optocouplers, independent of polarity
and are supplied via a constant current generator. The control signal is lead via a
debounce filter with a delay of 5 ms or 500 ms. EXT_TRIG, IN3 and IN4 work with the
same filter constant, which is usually set to 5 ms for photo cells, whereas IN2 is
operated with a filter constant of 500 ms if an encoder is connected.
Figure 6.18
Input wiring with control via PNP signal
Pin
Description
Function
18
EXT_TRIG A
External trigger (polarity exchangeable)
19
EXT_TRIG B
External trigger (polarity exchangeable)
6
IN2A
Input signal 2 (polarity exchangeable)
10
IN2B
Input signal 2 (polarity exchangeable)
14
IN3A
Input signal 3 (polarity exchangeable)
15
IN4A
Input signal 4 (polarity exchangeable)
24
IN_REF
Common reference earth for IN3 and IN4 (polarity
exchangeable)