Omron NX1P2 series User Manual page 127

 Blocks
A block consists of the Unit that supplies the NX Unit power and the range of Units to which that Unit
supplies the NX Unit power. For example, in the configuration in the following figure there are two
blocks in the CPU Rack: the block with the CPU Unit and the block with the Additional NX Unit
Power Supply Unit.
Unit power supply terminals
○
Internal
power
supply
circuit
Unit power
supply
(24 VDC)
The total of the required Unit power supply capacity for these two blocks is the required power sup-
ply capacity of the Unit power supply for the CPU Rack.
Precautions for Correct Use
Use the same Unit power supply to supply the Unit power to the one CPU Rack. If you supply
power from different Unit power supplies, differences in electrical potential may cause unex-
pected currents in the NX Unit power supply, which may result in failure or malfunction.
 Calculation Example
This section provides a calculation example for the configuration example that is given in 4-2-2 Cal-
culation Example for the NX Unit Power Supply on page 4-8.
Name
CPU Unit
Additional I/O Power Supply
Unit
Digital Input Unit
Relay Output Unit
• The NX Unit power supply efficiency of the CPU Unit is 80%.
In this configuration example, there is only one block, the CPU Unit block.
Required power supply capacity of Unit power supply to CPU Rack
= Required Unit power supply capacity of CPU Unit block
= (CPU Unit power consumption + Total power consumption from NX Unit power supply of NX
Units connected to CPU Unit)/NX Unit power supply efficiency of CPU Unit
= 7.05 W + (0.85 W × 1 + 0.90 W × 4 + 1.20 W × 3)/0.8
= Approx. 17.1 W
NX-series NX1P2 CPU Unit Hardware User's Manual (W578)
CPU Unit block
NX Unit connected to the
CPU Unit
NX-series
NX1P2 CPU
Internal
Unit
circuits
Internal
circuits
NX Unit power supply
Model
NX1P2-1140DT
NX-PF0630
NX-ID3317
NX-OC2633
4 Designing the Power Supply System
Additional NX Unit Power Supply Unit block
NX Unit connected to the Additional
NX Unit Power Supply Unit
Additional NX Unit
Power Supply Unit
Internal Internal Internal Internal
circuits circuits circuits circuits
Internal
power
supply
circuit
○
Unit power supply terminals
Quantity
1 7.05 W
1 0.85 W
4 0.90 W
3 1.20 W
End
Cover
Internal Internal Internal
circuits circuits circuits
NX Unit power supply
Power consumption/Unit
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