Connecting Thermocouples With Internal Compensation - Siemens SIMATIC S7-300 Manual

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.
Figure 4-14
S7-300 Automation System Module data
Manual, 08/2006, A5E00105505-04
Connecting thermocouples with internal compensation to electrically isolated analog
inputs
Priniples of analog value processing
4.6 Wiring thermocouples
4-15