Siemens Simatic S7-1500R System Manual page 110

Line voltage
The points to note for line voltage are set out below:
● For fixed plants or systems without multipole circuit breaker, a mains disconnection
device (multipole) must be available in the building installation.
● For the load power supply, the configured rated voltage range must correspond to the
local line voltage.
● For all power circuits of the S7-1500R/H redundant system, the fluctuation/deviation of
the line voltage from the rated value must be within the permitted tolerance.
You can find more information in the section Specifications for insulation tests, protection
class, degree of protection, and rated voltage (Page 300).
24 V DC supply
The points to note for a 24 V DC supply are set out below:
● Power supply units for the 24 V DC supply must supply safety extra low voltage in
accordance with IEC 61131-2 or IEC 61010-2-201.
● To protect the S7-1500R/H redundant system from lightning and overvoltages, use
overvoltage arresters.
Suitable components for the lightning and overvoltage protection are specified in the
Defining interference-free controllers
(http://support.automation.siemens.com/WW/view/en/59193566) function manual.
Protection against electrical shock
The mounting rails of the S7-1500R/H redundant system must be connected conductively to
the protective conductor to protect against electric shock.
Protection against external electrical influences
The following describes what you must pay attention to in terms of protection against
electrical influences and/or faults:
● The system for discharging electromagnetic interference must be connected to a
protective conductor with a sufficient cross-section for all plants with an S7-1500R/H
redundant system.
● You must ensure that all supply, signal and bus cables are correctly laid and installed.
● For signal and bus lines, a cable break, wire break or a cross-circuit must not lead to
undefined states in the plant or system.
Protection of redundancy connections against unauthorized access
Protect the redundant connections in a redundant S7-1500H system so that the fiber-optic
cables are protected against unauthorized access, e.g. by spatial access protection.
S7-1500R/H redundant system
System Manual, 10/2018, A5E41814787-AA
5.1 Rules and regulations for operation
Wiring
109