Siemens Simatic S7-1500 CPU 1512C-1 PN User Manual page 95

The figure below shows the current flow with correct wiring.
Figure 4-15
With correct wiring, the supply current flows from the power supply 2L+ via terminal 29 to the
module. In the module, the current flows via the output driver and exits the module via
terminal 40.
CPU 1512C-1 PN (6ES7512-1CK01-0AB0)
Manual, 12/2017, A5E40898741-AA
Current flow with correct wiring using the digital on-board I/O X11 as an example
4.3 Terminal and block diagrams
Wiring
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