&RQILJXULQJ
S7-300 Automation System, Hardware and Installation: CPU 31xC and CPU 31x
A5E00105492-03
5-27
$OO&38VH[FHSW&38[&
The figure below shows you the complete assembly of an S7-300 with TN-S mains
supply (does not apply to CPU 31xC).
Apart from powering the CPU, the PS 307 also supplies the load current for the
24 VDC modules.
Note: The arrangement displayed does not correspond with the physical
arrangement; it was merely selected to give you a clear overview.
Cabinet
Rail
PS
CPU
SM
Signal modules
L1
N
L+
M
µP
AC
AC
AC
AC
DC
DC
L1
M
L2
L3
N
PE
AC 24 to 230 V load circuit for AC modules
DC 5 to 60 V load circuit for
non-isolated DC modules
DC 5 to 60 V load circuit for
isolated DC modules
Low-voltage distribution
e. g. TN-S system (3 x 400 V)
Ground bus in cabinet
1
2
2
2
3
4
5
Figure 5-12 Grounding concept for the S7-300 (excluding CPU 31xC)
Table 5-11 Connection of the load voltage reference potential
7KHGLDJUDPLOOXVWUDWHVXQGHUQXPEHU
Main switch
Short-circuit/overload protection
Load power supply (galvanic isolation)
Disconnectable connection to protective conductor in order to localize ground faults
Grounding slide contact of the CPU (not CPU 31xC)
To Next Page
Loading...
Need help?
General
