OMRON NX102 Hardware Installation Guide

3.2 I/O Power Supply

Some NX units (such as digital I/O and analog) require I/O power supply to drive external sensors or loads. I/O power can be provided in the following ways:

Power supply through NX bus: An additional I/O power supply unit (such as NX-PF0630) needs to be inserted on the right side of the CPU, connected to an external 24VDC power supply, which supplies power to all I/O on the right side through the bus. The maximum total current is 10A.

External separate power supply: Some units come with I/O power terminals that can be directly connected to an external power source.

Hybrid power supply: If different groups of NX units require different voltages (such as 24V and 12V), or if a single 10A is insufficient, multiple additional I/O power supply units can be inserted to separate the circuits.

3.3 Power Capacity Calculation

Unit power supply: Total power consumption=CPU power consumption+∑ (internal power consumption of each NX unit). If the total power consumption is ≤ 10W, there is no need to add NX unit power supply. Otherwise, it needs to be divided into multiple segments.

I/O power supply: It is necessary to calculate the sum of I/O current consumption (including input current, output load current, sensor consumption current) of each unit, and consider the bus voltage drop. The voltage drop is related to the total current and the number of units passed through (voltage drop per unit ≈ 0.02V x total current (A)). Ensure that the power supply voltage of the farthest unit still meets its specifications.

Wiring and Grounding

4.1 Terminal block wiring

The CPU unit provides a detachable screw free clamping terminal block (model NX-TBC082, 8-terminal, including functional grounding terminal). Wiring method:

Strip the wire with a length of 8-10mm, use a needle shaped terminal with an insulated tube (Phoenix Contact AI series) or directly use stranded wire/single stranded wire.

For currents above 2A, it is necessary to use tin plated wires or tubular terminals.

Insertion method: Tilt a straight screwdriver 10-15 ° and insert it into the release hole (press to feel the spring rebound), maintain pressure, insert the wire or terminal into the circular terminal hole, and then pull out the screwdriver.

Wire fixing: If the current is greater than 2A and bare stranded wire is used, tie the wire bundle to the binding holes on both sides of the terminal block with zip ties.

4.2 Grounding

The functional grounding terminals (A7/B7) of the CPU unit must be grounded (grounding resistance ≤ 100 Ω). The recommended grounding wire is 2.0mm ² or larger.

DIN rails should also be grounded. If the surface of the guide rail is insulated (such as anodized aluminum), a DIN rail isolation gasket (NX-AUX01) should be used to isolate the guide rail from the backplate, and then grounded separately.

For EtherCAT/EtherNet/IP communication cables, it is recommended to use an equipotential bonding system or star grounding to avoid grounding loops. The shielding layers at both ends need to be connected to the connector housing, and the housing should be well grounded to the rack.

4.3 Power on sequence

To prevent output misoperation, the external circuit should ensure that the unit power supply of the controller is connected before the I/O power supply of the controlled system; When there is a power outage, the opposite is true. The controller takes about 20 seconds to start (depending on the configuration), during which the RUN indicator light flashes at 2-second intervals. At this time, the NX unit output is OFF, but the output behavior of the EtherCAT slave station depends on its parameter settings. System defined variables should be used in the program to confirm the establishment of communication before controlling.

Fault indicator light diagnosis

5.1 CPU unit status indicator light (located on the front)

Meaning of indicator light color and status

POWER green light, normal power supply

No power supply or voltage exceeding the limit

RUN green light, RUN mode running normally

2-second interval flashing startup (entering RUN/PROGRAMME)

2 seconds flashing continuously for ≥ 30 seconds, system initialization error

Extinguish Program mode, reset in progress, or major malfunction

ERROR red light indicates a major fault (control stopped) or CPU abnormality

Partial fault level error with 1-second interval flashing (a certain functional module stops) or minor fault (some functions are limited)

Eliminate normal or monitoring information

BUSY yellow flashing non-volatile memory access in progress

Eliminate idle time

SD PWR green, SD card powered on

Flashing backup/restore/compare operation in progress

SD card not powered or not inserted

SD BUSY yellow flashing SD card access in progress

Eliminate no access

Important: Do not turn off the power when the BUSY indicator light is flashing, otherwise it may cause the user's program or settings to not be saved correctly, and a major malfunction will occur when powered on next time.

5.2 EtherNet/IP Port Indicator Light (NET RUN/NET ERR/L/A)

NET RUN green light: normal startup; Flashing: Ethernet communication is in progress (such as tag data link establishment); Extinguish: Unable to communicate.