Omron Sysmac NX-PD1000 User Manual page 90

4 Installation and Wiring
 Calculation Example for Power Supply Capacity of I/O Power Supply
An example of calculating the required power supply capacity of the I/O power supply is given
below.
(a) Configuration and Conditions
Additional I/O
Power Supply Unit
NX-PF0730
I/O power
supply
(24 VDC)
I/O power supply voltage
Inputs
Outputs
I/O power is supplied to the NX-ID3317 and NX-OD3121 from the NX bus.
(b) Unit Specifications
Model
NX-PF0730
NX-ID3317
NX-OD3121
(c) Calculations
The current consumption from the I/O power supply for each Unit is calculated as follows.
NX-PF0730 Current Con-
sumption
NX-ID3317 Current Consump-
tion
NX-OD3121 Current Con-
sumption
4 - 30
Digital Input Digital
Unit Output Unit
NX-ID3317 NX-OD3121
Connected
Connected
output
input
devices
devices
(loads)
Item
Number of inputs used (that turn ON simultane-
ously)
Current consumption of connected input devices
Number of outputs (that turn ON simultaneously)
Load current of connected loads
Current consumption of connected output devices
Current consumption from I/O power supply
10 mA
0 mA
10 mA
= (Current consumption from I/O power supply)
= 10 mA
= (Current consumption from I/O power supply) + (Input current x Number of
inputs used) + (Total current consumption of connected input devices)
= 0 mA + (6 mA x 4 points) + (50 mA x 4 points)
= 224 mA
= (Current consumption from I/O power supply) + (Total load current of con-
nected loads) + (Total current consumption of connected output devices)
= 10 mA + (125 mA x 4 points) + (50 mA x 4 points)
= 710 mA
End Cover
Condition
24 VDC
4 points
50 mA/point
4 points
125 mA/point
50 mA/point
Input current
---
6 mA/point
---
NX-series System Units User's Manual (W523)