4
Designing the Power Supply Sys-
tem
This section describes how to design the power supply system for the NX-series
NX502 CPU Unit.
4-1
Power Supply System.................................................................................... 4-2
4-1-1 Unit Power Supply and I/O Power Supply....................................................... 4-2
4-1-2 NX-series Power Supply-related Units ............................................................ 4-4
4-1-3 X Bus Unit Power Supply ................................................................................ 4-9
4-2 Designing the NX Unit Power Supply System........................................... 4-11
4-2-1 Procedure for Designing the NX Unit Power Supply System .........................4-11
4-2-2 Calculation Example for the NX Unit Power Supply...................................... 4-12
4-3 Designing the I/O Power Supply System ................................................... 4-14
4-3-1 I/O Power Supply Method ............................................................................. 4-14
4-3-2 Designing the I/O Power Supply from the NX Bus ........................................ 4-15
4-3-3 Designing the I/O Power Supply from External Sources............................... 4-20
4-3-4 Restrictions on Inrush Current for ON/OFF Operation .................................. 4-20
4-4 Selecting External Power Supplies and Protective Devices.................... 4-22
4-4-1 Selecting the Unit Power Supply ................................................................... 4-22
4-4-2 Selecting the I/O Power Supplies.................................................................. 4-24
4-4-3 Selecting Protective Devices......................................................................... 4-25
4-1
NX-series NX502 CPU Unit Hardware User's Manual (W629)
4