Functions
Leuze electronic GmbH + Co. KG
CML 730i
34
4.9.1 External triggering
Trigger input
For an exact time assignment, it is possible to start the measurement cycle of a light curtain in a targeted
manner by means of a pulse at the trigger input. In this way, mutual interference can be prevented in appli
-
cations with multiple light curtains. This trigger signal generated in the control must be wired at all
cascaded light curtains.
The individual light curtains are configured so that the respective measurement is started with different
delay times to the trigger pulse (see figure 4.12).
1
PLC
2
Light curtain 1, delay time = 0 ms
3
Light curtain 2, delay time = 11 ms (depending on the cycle time LC1)
4
Trigger signal (PLC)
Figure 4.12: Activation via external trigger
4.9.2 Internal triggering
With internal trigger activation, a CML 700i configured as "master light curtain" generates the trigger pulse.
This trigger pulse is continuous; this means that no further activation is required from a primary control.
Trigger output
The trigger output of the master light curtain makes available the trigger signal necessary for “cascading
via internal trigger”. The trigger output must be wired to the trigger inputs of the slave light curtains (see
figure 4.13). This is used to start the measurement in the configured time sequence.
The following figure shows a wiring example for the cascading of three light curtains via internal trigger:
0
10
LV1
LV2
11
32
t [ms]
2
3
1
4
The cycle time of the respective light curtain can be read out via the
Sensor Studio
configuration
software (see chapter 16) or via the respective fieldbus interface (see chapter 10 et seq.).
The selection of activation via an internal or external trigger signal is made via the respective
fieldbus interface (see chapter 10 et seq.) or via the
Sensor Studio
configuration software (see
For an example configuration, see chapter 15.6.
