Protective Devices - Omron Sysmac NX-PD1000 User Manual

The required power supply capacity for the I/O power supply is calculated as follows.
Power supply capacity of I/O
power supply
4-5-3

Protective Devices

This section describes the protective devices to protect against short circuits and overcurrents of exter-
nal circuits.
Overcurrent means the current that flows when an excessive load is connected and one of the following
ratings is exceeded.
Unit name of supplying
Unit
Additional NX Unit Power
Supply Unit
Additional I/O Power Sup-
ply Unit
*1. When the Additional I/O Power Supply Unit is connected to the CPU Unit, use the I/O power supply current
at 4 A or less, regardless of the Additional I/O Power Supply Unit specifications.
Refer to the A-1 Data Sheet on page A-2 for details on the ratings for NX-series power sup-
ply-related Units.
Refer to the hardware user's manual for the connected CPU Unit or the user's manual for the con-
nected Communications Coupler Unit for the ratings of the CPU Unit or the Communications Cou-
pler Unit that can supply NX Unit power.
Refer to the user's manual for the connected Communications Coupler Unit for the ratings of the
Communications Coupler Unit that can supply I/O power.
Precautions for Safe Use
Use the I/O power supply current for the CPU Rack of NX1P2 CPU Unit at 4 A or less. Using
the currents that are outside of the specifications may cause failure or damage.
 Selecting Protective Devices
Refer to the hardware user's manual for the connected CPU Unit or the user's manual for the con-
nected Communications Coupler Unit for selecting the protective devices.
Refer to Required Power Supply Capacity on page 4-28 for information on the inrush current that
occurs when external devices connected to an Additional I/O Power Supply Unit are turned ON or
OFF, which is one of the items to consider when you select protective devices.
NX-series System Units User's Manual (W523)
= (Current consumed by NX-PF0730) + (Current consumed by NX-ID3317)
+ (Current consumed by NX-OD3121)
= 10 mA + 224 mA + 710 mA
= 944 mA
Connecting destination
of supplying Unit
NX1P2 CPU Unit or Com-
munications Coupler Unit
NX1P2 CPU Unit
Communications Coupler
Unit
4 Installation and Wiring
Rated item
NX Unit power supply Less than the rating of
capacity Additional NX Unit
Power Supply Unit
Current capacity of
power supply terminal
Maximum current of I/O
4 A max.
power supply
Current capacity of I/O
power supply terminals
Maximum current of I/O Less than the rating of
power supply Additional I/O Power
Supply Unit
Current capacity of I/O
power supply terminals
Rating
4
*1
4 - 31