Siemens Simatic S7-1500 Manual page 85

As a supplement to the block diagram and terminal assignment, the following figure shows
the correct wiring of the outputs in order to prevent switching of the outputs in the event of a
ground wire break.
Figure 4-13 Correct wiring using the digital on-board I/O X11 as an example
The ground is supplied with a first cable from the central terminal block to terminal 30 of the
module and additionally with a second cable also from the central terminal block to
terminal 40 of the module.
At the digital outputs, each of the ground connections of the loads is connected with a
separate cable for each load to the central terminal block.
CPU 1512C-1 PN (6ES7512-1CK00-0AB0)
Manual, 09/2016, A5E35306440-AB
4.3 Terminal and block diagrams
Wiring
85