User manual

Analog I/O expansion module Berghof Automationstechnik
18 2D0172002ZD00.DOC 2VF100051FE01.doc
2.7.4. Measuring
The measurements and transfer of the data from the module to the CAN node are
carried out in a cyclic manner, controlled via the API (Application Process Interface)
in the operating system. No start signals have to be output for AD conversion.
Execution of the measuring process depends on the software environment used.
For this reason, you should consult the relevant information contained in the pro-
gramming manuals for CP1131 or CPC++.
Note::
The following formula applies for converting the measured data into voltage
values:
AD AD
U = 10 V
2
15
I = 20 mA
2
15
Comment:
AD = the value supplied by the analog channel (in_value)
When leaving the permissible measuring range, the following values are reported:
Exceeding the permissible measuring range (+) + 32752 + 9,995 V
Falling short of the permissible measuring range (-) - 32768 - 10,000 V
Representation of the 11-bit measured value with sign in a 16-bit variable:
2VF100070DG00.cdr
2.7.5. Sensor failure
In the case of sensor failure, the corresponding channel reports the value for
+9.995 V to the cell controller.