Omron NX Series - Processing at Power on and Power off; Power on Operation

5-1
Processing at Power ON and Power
OFF
WARNING
• Do not touch any of the terminals or terminal blocks while the power is being sup-
plied.
Doing so may result in electric shock.
•
Do not attempt to take any Unit apart.
In particular
, high-voltage parts are present in the Power Supply Unit while power is
supplied or immediately after power is turned OFF. Touching any of these parts may
result in electric shock. There are sharp parts inside the Unit that may cause injury.
5-1-1
Power ON Operation
Precautions for Safe Use
It takes a certain time for startup to enter RUN mode after the power supply is turned ON, de-
pending on the type and configuration of the Unit and its settings.
During startup, the outputs for NX Units on the CPU Rack will be OFF. Note that the outputs on
the slaves will behave according to the setting values.
Therefore, use the system-defined variables and the device variables for each Unit in the user
program to confirm that startup processing and I/O data communications are established before
attempting control operations.
External communications are also not performed during startup.
Operation Until Operation Ready Status
Once the Unit power supply to the Unit power supply terminal starts, a certain time elapses depending
on the type and configuration of the Unit and its settings before the CPU Unit enters the operation-
ready status. This period is called the startup status
.
The startup time depends on the slave/NX Unit configuration
*1
, user program, SD Memory Card us-
age, SD Memory Card self-diagnosis usage
*2
, etc.
While the CPU Unit is in the startup status, the RUN indicator flashes at a one second interval.
*1. Some EtherCAT slaves can set a maximum standby time of 1 to 200 seconds. For the CPU Unit, however, the
operation-ready status exists as soon as the EtherCAT Master Function Module is functioning, regardless of
the standby time of the EtherCA
T slaves. For the EtherCAT Master Function Module, slaves that do not start
within the maximum waiting time are treated as having an error.
*2. This function performs self-diagnosis on the inserted SD Memory Card. This is executed if the self-diagnosis
at startup is enabled in the Operation Settings under Configurations and Setup − Controller Setup in the
Sysmac Studio.
The following processing is performed during the startup status of the CPU Unit.
Process Description
Self diagnosis at startup Operation is monitored for the following errors: Power Supply Er-
ror
, CPU Unit Error
, Hardware Initialization Error, and System Ini-
tialization Error.
*1
5 Installation and Wiring
5-2
NX-series NX502 CPU Unit Hardware User's Manual (W629)