Siemens SIMATIC S7-300 Module data User Manual

Priniples of analog value processing
4.6 Wiring thermocouples
S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04
4-15
See also
Connecting thermocouples with internal compensation (Page 4-15)
Connecting thermocouples with external compensation (Page 4-16)
Sensors which can be connected to analog inputs (Page 4-1)
4.6.1 Connecting thermocouples with internal compensation
Function principle of internal compensation
Internal compensation allows you to form the reference point at the terminals of the analog
input module. In this case, route the compensating lines directly to the analog module. The
internal temperature sensor measures the module's temperature and returns a
compensation voltage.
Please note: internal compensation is not as accurate as external compensation.
Connecting thermocouples with internal compensation
Wire the thermocouples either directly to the inputs of the module, or indirectly via
compensating lines. Each channel group can use any type of thermocouple supported by the
analog module, independently of other channel groups.
0
0ದ
0
0ದ
/
0
&+
&+
/RJLF
$'&
%DFNSODQH
EXV
(TXDOL]LQJFRQGXFWRU
VDPHPDWHULDO
DVWKHUPRFRXSOH
7KHUPRFRXSOH
Figure 4-14 Connecting thermocouples with internal compensation to electrically isolated analog
inputs

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)