Analog Inputs: I7 And I8; Connecting A Potentiometer To Inputs I7 / I8 - Siemens Logo! Manual

Note
The high-speed inputs I5 and I6 are the same as in the
previous versions 0BA0 to 0BA4, i.e. a circuit program that
is written in these versions can be transferred to the new
0BA5 units by means of the programming software LOGO!
SoftComfort, without any changes to these features. In
contrast to this, you need to modify circuit programs written
for a LOGO!...L version (high-speed inputs I11/I12).
Expansion modules do not have high-speed inputs.
S

Analog inputs: I7 and I8

The inputs I7 and I8 of LOGO! versions 12/24RC/RCo and
24/24o can be used both as standard digital inputs and as
analog inputs. The input mode is defined in the LOGO!
circuit program.
The inputs I7 / I8 provide digital functions, and the inputs
AI1 and AI2 provide analog functions.
See also Chapter 4.1.
When using inputs I7 and I8 as analog ones, only the range
from 0 to 10 V DC is available.

Connecting a potentiometer to inputs I7 / I8

To allow you to achieve 10 V as the maximum value when
you completely turn the potentiometer once, you must con-
nect a series resistor on the potentiometer's input side re-
gardless of the input voltage.
We suggest the following sizes of potentiometers and asso-
ciated series resistors:
Voltage
LOGO! Manual
A5E00380835-01
Potentiometer
12 V
24 V
LOGO! installation and wiring
Series Resistor
5
kW
5
kW
–
6,6
kW
35