143
ifm Vision Assistant O3M
UK
15.3.3 Example for "Analogue CAN input signals" module
In logic, the "Analogue CAN input signals" module is used to process the motion speed of a machine . The
calculated values are used to adjust the size of the warning range of the machine .
A programmable controller is connected to the device as follows:
2
PLC
3
CAN
4
O3M
1
INPUT
Description of the devices and interfaces used:
Number
Function
Description
1
Input value
The speed is applied as a scaling value to the analogue input of the programmable
controller (current or voltage) .
2
Programmable controller
(e .g . CR0403)
The programmable controller converts the values to a 12-bit CAN value between
0 . . .1 um .
3
CAN interface
The CAN interface transmits the motion speed in 12-bit resolution .
4
Device (e .g . O3M251)
The device uses the analogue input value to scale the warning range .
Description of the modules used in the example:
Module number
Module
Description
1
Basic function
The x value is filtered out of ROI group 1 .
2
Analogue CAN input
signals
The CAN input values from the controller are processed at analogue input 1 .
Previously, the controller has scaled the values to the range 0 . . .1 .
3
Fixed value
The fixed value "10" defines the maximum warning distance in metres .
4
MULT
The speed value is multiplied by the maximum warning distance . This calculates
the threshold value (warning value) . The threshold value is dynamic (depending on
the speed at the analogue input) .
5
Basic function
The validity of ROI group 1 is checked .
6
Less than or equal
It is checked whether the current measured distance value is less than or equal to
(<=) the speed-dependent warning value .
7
AND
If the measurement is valid (module 5) and the measured distance value <= the
warning value (module 6), a "1" is provided .
8
Digital output
Digital output 1 applies the binary information to the CAN output . The value is
provided via the controller as a physical output .
