Siemens SIMATIC S7-300 Module data Reference Manual

Analog Modules
4-62
Programmable Logic Controllers S7-300 Module Data
A5E00105505-03
Connecting thermocouples with compensating box
If all thermocouples connected to the inputs of the module have the same
comparison point, you compensate as follows:
M+
M–
M+
M–
Backplane
bus
ADC
M
L+
Compensating
leads (same
material as
thermocouple)
Box
Comp.
Ref. junction
ML+
Copper
wire
COMP
–
/M
ANA
COMP
+
Thermo-
couples
Logic
Figure 4-24 Connection of Thermocouples with Compensation Box to an Isolated AI
Note
Use compensating boxes with a reference junction temperature of 0C for
analog input modules.
Recommended compensating box
We recommend you to use a comparison point (with integrated power supply unit)
from Siemens as a compensating box. You will find the necessary ordering data in
the table below.

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)