Siemens SIMATIC ET 200iSP Operating Instructions Manual page 104

Wiring
5.1 General Rules and Regulations for Wiring
Line voltage in the safe area
The following table describes points to remember relating to the line voltage:
Table 5-2
With ...
A fixed installation or systems without all-pole dis‐
connector
Load power supplies, power supply modules
All circuits of the ET 200iSP distributed I/O station Any fluctuation/deviation in the supply voltage
24 VDC supply in safe area
The following table shows what you have to note with the 24 VDC supply:
Table 5-3
With ...
Buildings
24 VDC supply lines, signal
lines
24 VDC supply
Protection against exterior electric effects
The following table shows what you have to note to protect against electric effects or faults:
Table 5-4
With ...
All systems in which ET 200iSP is installed
Supply, signal and bus lines
Signal and bus lines
104
Line voltage in the safe area
24 VDC supply in the safe area
you must note the following...
exterior lightning protection
Interior lightning protection
Safety isolation
Protection against exterior electric effects
Requirements
A disconnector or a fuse must exist in the building
installation.
The set rated voltage range must correspond to
the local line voltage.
from the rated value must be within the permitted
tolerance (refer to "General technical specifica‐
tions (Page 195)").
Provide lightning protection meas‐
ures (e.g. overvoltage suppressor)
you must note the following...
That the system for discharging electromagnetic
faults is connected to a PE conductor.
The wiring arrangement and installation must be
correct.
that a cable or wire break cannot lead to undefined
system states.
Operating Instructions, 11/2017, A5E00247483-07
ET 200iSP