Mechanical and electrical configuration
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X20 system User's Manual 3.10
3.8 The supply concept
Danger!
In order to guarantee a specific supply voltage, a SELV power supply that conforms to IEC 60204 must
be used to supply the bus and I/O.
3.8.1 Bus module rack replacement
Bus supply contacts
Bus data contacts
I/O supply contacts
X20BM11
X20BM01
Figure 31: The bus module replaces the rack in the X20 system
The bus module is the backbone of the X20 system regarding the bus supply and bus data as well as the I/O supply
for the electronics modules. Each bus module is an active bus station, even without an electronics module. There
are two variations of the bus module:
•
Interconnected I/O supply
•
I/O supply isolated to the left (for power supply modules)