Siemens SIMATIC S7-1500 System Manual page 42

Installation
4.2 Installing the mounting rail
Attaching the protective conductor
The S7-1500 automation system/ ET 200MP distributed I/O system has to be connected to
the protective conductor system of the electrical system to ensure electrical safety.
To connect the protective conductor, follow these steps:
1. Strip the grounding conductor with a minimum diameter of 10 mm
terminal for size M6 bolts with the crimping pliers.
2. Slide the enclosed bolt into the T profile groove.
3. Insert the spacer, ring terminal with the grounding connector, flat washer, and lock
washer onto the bolt (in that order). Thread the hexagon head nut, and fasten the
components in place with the nut (torque 4 Nm).
4. Connect the opposite end of the grounding cable to the central grounding point/protective
conductor busbar (PE).
Figure 4-3
Note
Alternative grounding of the mounting rail
If it is ensured that the mounting rail is permanently connected to the protective conductor
system using an equivalent installation that complies with standards, for example, by
permanent attachment to a grounded control cabinet wall, grounding via the grounding screw
can be omitted.
Reference
Additional information on the precise dimensions of the mounting rails can be found in the
Dimension drawings of the mounting rails (Page 217) section.
42
Attaching the protective conductor
and attach a ring
2
Automation system
System Manual, 12/2014, A5E03461182-AC