Siemens SIMATIC S7-300 Module data Reference Manual

Analog Modules
4-46
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Abbreviations and mnemonics used in the figures below
The abbreviations and mnemonics used in the figures below have the following
meanings:
M +: Measuring lead (positive)
M–: Measuring lead (negative)
M
ANA
: Reference potential of the analog measuring circuit
M: Ground terminal
L +: Terminal for 24 VDC supply voltage
U
CM
: Potential difference between inputs and reference potential of
the M
ANA measuring circuit
U
ISO
: Potential difference between M
ANA
and M terminal of CPU
I +: Measuring lead for current input
U +: Measuring lead for voltage input
Connecting isolated measuring sensors
Isolated sensors are not connected with the local ground potential (local ground).
They can be operated free of potential.
With isolated sensors, potential differences might arise between the different
sensors. These potential differences can arise as a result of interference or the
local distribution of the sensors.
To prevent the permissible value for U
CM
being exceeded when used in
environments with a high level of EMC interference, we advise you to connect M–
with M
ANA
.

Siemens SIMATIC S7-300 Module data Specifications

General

Series	S7-300
Manufacturer	Siemens
Protection Class	IP20
System	SIMATIC S7-300
Digital Inputs	Varies by module
Digital Outputs	Varies by module
Analog Inputs	Varies by module
Analog Outputs	Varies by module
Central Processing Unit	Varies by CPU model
Supply Voltage	24V DC or 120/230V AC
CPU Type	Varies (e.g., CPU 312, CPU 315, etc.)
Memory	Varies by CPU model
Communication Interfaces	MPI, PROFIBUS
Programming Languages	LAD, FBD, STL, SCL, GRAPH
Operating Temperature	0°C to 60°C
Storage Temperature	-40°C to 70°C
Relative Humidity	10% to 95% (non-condensing)