Omron PROFINET NX-PNC202 User Manual page 83

●The total current consumption from the I/O
power supply must not exceed the
maximum current of the I/O power supply.
(NX Units that are supplied power from
external sources are not included in the
calculation.)
●The voltage drop in the I/O power supply
must be within the voltage specifications
of the I/O circuits of the NX Units and the
connected external devices.
PROFINET
Coupler Unit
I/O power supply
terminals
To external
I/O power
devices
supply
 Maximum IO Power Supply Current
The maximum IO power supply current is the maximum current that the IO power supply that is con-
nected to the PROFINET Coupler Unit or Additional IO Power Supply Unit can supply through the
NX bus connectors to the NX Units. For the maximum IO power supply current of the PROFINET
Coupler Unit, refer to 3-1-3 PROFINET Coupler Unit Specifications on page 3-4. For the maximum
IO power supply current of the Additional IO Power Supply Unit, refer to the NX-series System Units
User's Manual (Cat. No. W523).
Calculating the Total Current Consumption from the IO Power Sup-
ply
The total current consumption from the IO power supply from the NX bus is the total of the following
current consumptions.
• The current consumption from the IO power supply that is required for the PROFINET Coupler Unit
or the Additional IO Power Supply Unit, and for the NX Units that are connected to the PROFINET
Coupler Unit or Additional IO Power Supply Unit
• The current consumption between the NX Units and the connected external devices
Current consumption item
Current consumption from IO
power supply
NX-series PROFINET Coupler Unit User's Manual (W623)
●The total current consumption
from the I/O power supply
must not exceed the
maximum current of the I/O
power supply.
●The voltage drop in the I/O
power supply must be within
the voltage specifications of
the I/O circuits of the NX
Units and the connected
external devices.
Additional I/O Power Supply Unit
NX Units
I/O power
To external
supply
devices
terminals
I/O I/O
I/O power
power power
supply
supply supply
Supplied from
The Additional I/O Power
external source.
Supply Unit is used because
otherwise the maximum
current of the I/O power supply
would be exceeded.
This is the current that is consumed by the internal circuits that operate on
the IO power supply.
Specific values are given in the user's manuals for individual Units.
5 Designing the Power Supply System
●The total current consumption
from the I/O power supply
must not exceed the
maximum current of the I/O
power supply.
●The voltage drop in the I/O
power supply must be within
the voltage specifications of
the I/O circuits of the NX
Units and the connected
external devices.
Additional I/O Power Supply Unit
NX Units
NX Units
I/O power
To external To external
supply
devices
terminals
I/O power
supply
Separating the I/O
Power Supply
• The Additional I/O
Power Supply Unit is
used because
different I/O power
supply voltages are
used.
Description
End Cover
devices
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