Siemens SIMATIC S7-1500 Manual page 13

Abbreviations used
Meaning of the abbreviations used in the following figure:
xL+
xM
CHx
PWRx
The figure below shows you how to connect the module and the assignment of the channels
to the addresses (input byte a and b, output byte c and d).
①
Figure 3-1
Digital input/output module DI 16x24VDC/DQ 16x24VDC/0.5A BA (6ES7523-1BL00-0AA0)
Manual, 09/2014, A5E32364588-AB
Supply voltage connector
Ground connector
Channel or display for the channel status
Display for the supply voltage (POWER)
Backplane bus interface
Block diagram and terminal assignment
3.1 Wiring and block diagram
Wiring
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