Siemens simatic c7-621 Hardware Installation Manual page 95

Channels Three pins are grouped together to form a channel.
Table 7-1
Connection to an Only an analog sensor can be connected to an analog input channel.
Analog Input
Voltage Measurement
Figure 7-8
Current Measurement
Figure 7-9
C7-621 / C7-621 AS-i Control Systems
C79000-G7076-C621-01
Channels of the Analog Input Module
Pin Value
Name
AI1-U Voltage input
AI1-I Current input
AI1-M Reference potential
AI2-U Voltage input
AI2-I Current input
AI2-M Reference potential
AI3-U Voltage input
AI3-I Current input
AI3-M Reference potential
AI4-U Voltage input
AI4-I Current input
AI4-M Reference potential
Voltage
Current
Reference potential
Connection of a Channel for Voltage Measurement
Voltage
Current
Reference potential
Connection of a Channel for Current Measurement
C7-621 Analog I/Os
Channel
Channel 1 (AI1)
Channel 2 (AI2)
Channel 3 (AI3)
Channel 4 (AI4)
Single channel voltage measurement
Single channel current measurement
7-13