Motion
1
Moving forward
2
Moving backward
3
Moving forward again
Single-channel encoder
A single-channel encoder uses only one encoder channel. The input from the encoder
to the camera is a differential signal, and a profile is triggered each time the signal
goes high.
When a single-channel encoder is used, the camera cannot differentiate between for‐
ward and backward movement. The single-channel encoder mode (
EncoderMode
= Sin‐
gleChannel) is therefore only visible and selecteable when the
EncoderOutputMode
(see
) is set to Motion.
7.11.4
Frame triggering
The Frame trigger input is used to trigger the camera to start to acquire profiles when
the object passes a photoelectric switch. If the same photoelectric switch is connected
to several cameras then synchronization at the microsecond level can be achieved.
When using the Frame trigger input, the
Height[Scan3dExtraction1]
parameter specifies
the number of profiles that the camera acquires after the Frame trigger signal goes
high. After the specified number of profiles, the camera will either idle or continue to
acquire another series of profiles, depending on the state of the Frame trigger signal
and the settings of the acquisition control parameters. See the table and the figure
below.
Parameter settings
TriggerSelector
= FrameStart
TriggerMode[TriggerSelector]
= Off
•
The camera acquires profiles continuously.
TriggerSelector
= FrameStart
TriggerMode[TriggerSelector]
= On
•
The acquisition of a new series of profiles (that is, captur‐
ing of a new frame) starts each time the Frame trigger
input has a high level as input.
•
Multiple Frame trigger signals are ignored until all profiles
(as specified by
Height[Scan3dExtraction1]
) have been
acquired.
•
Note that for the very first profile the camera requires not
only a high level but also a rising edge.
The system adapts the buffer height for the frame grabber and the camera to the
Height[Scan3dExtraction1]
parameter to keep the image synchronized and receive a full
image after the image capture is completed. To avoid unnecessary CPU load, set the
Height[Scan3dExtraction1]
parameter to no less than 100 pixels.
0 V
24 V
Height
Height
Height
Frame
trigger
signal
1
Profile acquisition
(level sensitive)
2
3
4
5
Figure 18: Timing diagram for Frame trigger signal
1
Frame trigger signal
2
Profile acquisition (level sensitive)
7
CONFIGURATION
34
O P E R A T I N G I N S T R U C T I O N S | Ranger3
8020774/14IM/2019-07 | SICK
Subject to change without notice