Siemens Simatic S7-300 - Measuring Ranges of the SM 334;AI 4;AO 2 X 12 Bits

Analog Modules
4-199
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Note
Simultaneous connection of a temperature sensor and a resistor to channels 0 and
1 and 2 and 3 is not allowed.
The reason common current source for both channels.
Unused Channels
Set the “measuring method” parameter for unused input channels to “disabled”. In
this way you shorten the scan time of the module.
You must short-circuit unused input channels and you should connect them to
M
ANA
. In this way, you obtain an optimum interference immunity for the analog
input module.
So that unused output channels of the SM 334; AI 4/AO 2 x 12 bits remain
de-energized, you must set the “output type” parameter to “disabled” and leave the
terminal open.
Measuring ranges
Use STEP 7 for programming the measuring ranges.
Table 4-87 Measuring ranges of the SM 334;AI 4/AO 2 x 12 bits
Method Selected
Measuring Range Description
U: Voltage 0 to 10 V You will find the digital
analog values in Section
R-4L: Resistance (four-conductor
connection)
10 k
analog values in Section
4.3.1
RTD-4L: Bulb resistor
(linear, four-conductor connection)
(temperature measurement)
Pt 100 climate
Default settings of inputs
The default settings of the module are the “Bulb resistor (linear, four-conductor
connection)” measuring method and the “Pt 100 climate” measuring range. You
can use this combination of measuring method and measuring range without
parameterizing the SM 334; AI 4/AO 2 x 12 bits in STEP 7.