Siemens M7-400 User Manual

5-51

S7-400, M7-400 Programmable Controllers Module Specifications
A5E00069467-07

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).

Make sure that the connected cables I

+ and M+ and SO and SE+ and cables

– and M– and AGND and SE– are connected directly on the resistance

thermometer.

I

C

M

+

M

–

I

C+

I

C–

SE+
SE–
SO
AGND

Figure 5-14

Four-Conductor Connection of Resistance Thermometers on an AI