Internal power
supply circuit
CPU Unit block
Additional NX Unit Power
Supply Unit block
NX Unit connected to the Additional
NX Unit Power Supply Unit
Additional NX Unit
Power Supply Unit
Unit power
supply terminals
NX Unit connected
to the CPU Unit
Unit power supply terminals
End Cover
Unit Power
Supply
NX Unit power supplyNX Unit power supply
NX-series
CPU Unit
Internal power
supply circuit
The total Unit power supply capacity for these two blocks is the power supply capacity that the
CPU Rack requires.
Precautions for Correct Use
Select a Unit power supply with sufficient capacity by considering the inrush current when the
power is turned ON. Sometimes, the Unit power supply may not be turned ON caused by inrush
current when the power is turned ON.
Equation in the Slave Terminal
<Equation>
The equation for the Unit power supply capacity in the Slave T
erminal is as follows.
Unit power supply capacity in the Slave T
erminal = Total power capacity from Unit power supply on each
block
The equation for the Unit power supply capacity on each block in the Slave Terminal is as follows.
Required Unit power supply capacity of each block = ((A) + (B))/(C)
(A): NX Unit power consumption of the Unit that supplies NX Unit power
(B): Total power consumption from the NX Unit power supply that is required by the NX Units that are connected to
the Unit that supplies NX Unit power
(C): NX Unit power supply ef
ficiency of the Unit that supplies NX Unit power
<Block>
The following shows the Unit that supplies NX Unit power and its supplying range. For example,
the Slave Terminal in the following diagram is configured with two blocks: the Communications
Coupler Unit block and the Additional NX Unit Power Supply Unit block.
4 Installation and Wiring
4-30
NX-series System Units User's Manual (W523)