Siemens SIMATIC ET 200SP System Manual

Wiring
6.4 Operating the ET 200SP on grounded incoming supply
Distributed I/O system
System Manual, 09/2019, A5E03576849-AJ
93
Grounded extra-low voltage (PELV in accordance with IEC 61131-2 or IEC 61010-2-201)
Load power supplies/power supply modules with grounded 24 V DC output voltage require
safe connection to the protective conductor and voltage limiting (extra low voltage).
According to IEC 61131-2 and IEC 61010-2-201, this protection is referred to as PELV
(Protective Extra Low Voltage).
The wiring of PELV circuits must be safely separated from the wiring of other circuits that are
not PELV, or the insulation of all conductors must be dimensioned for the higher voltage.
Configuration of ET 200SP with ungrounded reference potential
To conduct interference currents, the reference potential of the CPU/interface module and
the BaseUnits BU15...D is connected internally via an RC combination (IM/CPU:
R = 10 MΩ / C = 100 nF, BU15...D: R = 10 MΩ / C = 4 nF) with the mounting rail (functional
grounding).
● This configuration conducts high-frequency interference currents and prevents static
charges.
● It is always possible to configure an ungrounded setup of the ET 200SP distributed I/O
system as the ET 200SP distributed I/O system has no fixed ground connection. The
power pack/power supply module for 24 V DC must also be ungrounded and electrically
isolated.
If you want to configure the ET 200SP distributed I/O system with grounded reference
potential, connect the 1M connection of the CPU/interface module electrically with the
protective conductor.
Short-circuit / overload protection
Various measures as protection against short-circuits and overloads are required for setting
up a full installation. The type of components and the binding protective measures depend
on which IEC (DIN VDE) regulation applies to your system configuration. The table refers to
the figure below and compares the IEC (DIN VDE) regulations.
Table 6- 1 Components and protective measures
Refer to figure
IEC 60364 (DIN VDE 0100)
IEC 60204 (DIN VDE 0113)
Disconnecting device for controller,
sensors, and actuators
①
Main switch Disconnector
Short-circuit / overload protection:
In groups for sensors and actuators
②
③
Single-pole protection of
circuits
With grounded secondary
circuit:
single-pole
protection
otherwise:
all-pole
protection
Load current supply for AC load cir-
cuits with more than five items of
electromagnetic equipment
②
Galvanic isolation by trans-
former
recommended
Galvanic isolation by trans-
former
recommended

Siemens SIMATIC ET 200SP Specifications

General

System Type	Distributed I/O System
Mounting	DIN Rail
Communication Protocol	PROFINET, PROFIBUS
IP Rating	IP20
Category	I/O Systems
Supply Voltage	24 V DC
Modularity	Yes
Hot Swapping	Yes
Storage Temperature	-40°C to +70°C
Digital Inputs	Yes
Digital Outputs	Yes
Analog Inputs	Yes
Analog Outputs	Yes
Communication Interface	PROFINET, PROFIBUS
Number of Modules	Up to 64
Relative Humidity	5 to 95% (non-condensing)
Operating Temperature	-25°C to +60°C