Siemens SIMATIC S7-300 Module data Reference Manual

Analog Modules
4-54
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Four-conductor connection of a resistance thermometer
The voltage generated at the resistance thermometer is measured via the M
+
and
M
–
terminals. When you connect, watch out for the polarity of the connected cable
(connect I
C+
and M
+
as well as I
C–
and M– to the resistance thermometer).
When connecting, make sure that the connected cables I
C
+ and M+ and the
cables I
C
– and M– are connected directly to the resistance thermometer.
M+
M
L+
M–
M
ANA
ADC
I
C+
I
C–
I
C
Backplane
bus
Logic
Figure 4-15 Four-conductor connection of resistance thermometers to an isolated AI
Three-conductor connection of a resistance thermometer
With a three-conductor connection on modules with four terminals, you must
normally insert a jumper between M
–
and I
C–
(refer to Figure 4-16). Take note of
the exception for the SM 331; AI 8 RTD (refer to Figure 4-18).
When connecting, make sure that the connected cables I
C
+ and M+ are
connected directly to the resistance thermometer.
M+
M
L+
M–
M
ANA
ADC
I
C+
I
C–
I
C
Backplane
bus
Logic
Figure 4-16 Three-Conductor Connection of Resistance Thermometers to an Isolated AI

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)