Non-Fatal Error In Cpu Unit - Omron NJ-series User Manual

12 Troubleshooting

12-1-3 Non-fatal error in CPU Unit

Event Levels
Non-fatal errors that occur are managed as Controller events in the NJ-series Controller. Controller
events are classified into levels according to the degree of the effect that the events have on control.
When an event occurs, the Sysmac Studio or PT will display the level. Refer to the NJ-series Trouble-
shooting Manual (Cat. No. W503) for details on Controller events.
• Major Fault Level
These errors prevent control operations for the entire Controller. If a major fault level error is detected,
user program execution is stopped immediately and the loads for all slaves (including remote I/O) are
turned OFF. With EtherCAT slaves and some CJ-series Special Units, you can set the slave settings
or Unit settings to select whether outputs will go OFF or retain their previous status. You cannot reset
major fault level errors from the user program, the Sysmac Studio, or an NS-series PT. To recover
from a major fault level error, remove the cause of the error, and either cycle the power supply to the
Controller or reset the Controller from the Sysmac Studio.
• Partial Fault Level
These errors prevent control operations in a certain function module in the Controller. The NJ-series
CPU Unit continues to execute the user program even after a partial fault level error occurs. You can
include error processing in the user program to safely stop any devices in operation. After you
remove the cause of the error, execute one of the following to return to normal status.
• Reset the error from the user program, the Sysmac Studio, or an NS-series PT.
• Cycle the power supply.
• Reset the Controller from the Sysmac Studio.
• Minor Fault Level
These errors prevent part of the control operations in a certain function module in the Controller. The
troubleshooting for minor fault level errors is the same as the processing for partial fault level errors.
• Observations
These errors do not affect the control operations of the Controller. Observations serve as warnings to
the user so that the error does not develop into an error at a higher level.
• Information
Events that are classified as information do not indicate errors.
12-4 NJ-series CPU Unit Software User's Manual (W501)