Omron NX-ECC201 User Manual page 94

5 Designing the Power Supply System
 Maximum I/O Power Supply Current
The maximum I/O power supply current is the maximum current that the I/O power supply that is
connected to the EtherCAT Coupler Unit or Additional I/O Power Supply Unit can supply through the
NX bus connectors to the NX Units. For the maximum I/O power supply current of the EtherCAT
Coupler Unit, refer to 3-1-2 EtherCAT Coupler Unit Specifications on page 3-2. For the maximum I/O
power supply current of the Additional I/O Power Supply Unit, refer to the NX-series System Units
User's Manual (Cat. No. W523).
Calculating the Total Current Consumption from the I/O Power Sup-
ply
The total current consumption from the I/O power supply from the NX bus is the total of the following
current consumptions.
• The current consumption from the I/O power supply that is required for the EtherCAT Coupler Unit or
the Additional I/O Power Supply Unit, and for the NX Units that are connected to the EtherCAT Cou-
pler Unit or Additional I/O Power Supply Unit
• The current consumption between the NX Units and the connected external devices
Current consumption item
Current consumption from I/O
power supply
Current consumption between
the NX Units and the connected
external devices
 Calculation Examples
Examples of calculating the current consumption from the I/O power supply are given below for a
Digital Input Unit and Digital Output Unit.
Current consumption of Digital
Input Unit
Current consumption of Digital
Output Unit
5 - 12
This is the current that is consumed by the internal circuits that operate on
the I/O power supply.
Specific values are given in the user's manuals for individual Units.
This is the current that is consumed between the NX Units and the con-
nected external devices.
For example, this is the current consumed by a Digital Input Unit to supply
power to photoelectric sensors or to turn ON the input circuits in the Digital
Input Unit.
The current consumption depends on the type of I/O circuit in the NX Unit,
the number of I/O points that are used, and the current consumption of the
connected external device. It must be calculated for each NX Unit.
Current consumption from I/O power supply + (Input current × Number
=
of inputs used) + Total current consumption of connected input devices
Current consumption from I/O power supply + Total load current of con-
=
nected loads + Total current consumption of connected output devices
NX-series EtherCAT Coupler Unit User's Manual (W519)
Description