Connecting; Safety Regulations - Siemens SIMATIC TOP connect Manual

Connecting

4.1

Safety regulations

Introduction
When used in plants or systems, SIMATIC TOP connect system cabling is subject to special
rules and regulations in line with the area of application.
This section provides an overview of the most important rules for connecting SIMATIC TOP
connect.
You can also find rules and regulations governing the integration of the S7-300 into a plant or
system in the section "Basic Rules and Regulations" in the "SIMATIC Automation Systems
S7-300, ET 200M I/O Modules"
1096709) manual.
Specific application scenario
Please observe the safety and accident prevention regulations that apply to specific
applications, for example, the machinery directives.
Line voltage
Note the line voltage:
● For stationary plants and systems without an all-pole line disconnector, there must be a
disconnector unit (all-pole) fitted in the building installation.
● Any fluctuation/deviation in the line voltage from the rated value must be within the permitted
tolerance for all S7-300 electric circuits.
24 V DC supply
Note the following for the 24 V DC supply:
● Power supplies for 24 V DC must have secure electrical isolation in accordance with IEC
60364-4-41.
● Surge arrestors must be fitted to protect against lighting and overvoltage.
You can find components for lightning and overvoltage protection in the "Designing
interference-free controllers" function manual
view/en/59193566).
Protection from electric shock
The S7-300 automation system mounting rail must be connected (conductive connection) to
the protective conductor to prevent electric shock.
System cabling for S7-300
Manual, 09/2018, 70327045899
(http://support.automation.siemens.com/WW/view/en/
(http://support.automation.siemens.com/WW/
4
21