Troubleshooting; Checking To See If The Cpu Unit Is Operating - Omron NJ501-1400 User Manual

5-2

Troubleshooting

This section provides basic error identification and troubleshooting flowcharts. Use them when an error
occurs in the NJ-series Controller. This section also describes the hardware errors that are related to
the PLC Function Module and corrections for those errors.
5-2-1

Checking to See If the CPU Unit Is Operating

When an error occurs in the NJ-series Controller, use the following flowchart to determine whether the
error is a fatal error or a non-fatal error.
Whenever possible, set the Sysmac Studio's communications connection in the flowchart to a direct
USB connection. If you use Ethernet, there are many reasons that prevent a communications connec-
tion for the Sysmac Studio, so time is required to determine if a fatal or non-fatal error has occurred. If a
communications connection from the Sysmac Studio is not possible, perform the troubleshooting proce-
dure that is provided in the NJ/NX-series Troubleshooting Manual (Cat. No. W503) before you assume
that the error is a fatal error.
Error occurs.
PWR indicator (green)?
Flashing.
ERROR indicator (red)?
RUN indicator (green)?
Communications
with Sysmac
Studio?
A
NJ-series CPU Unit Hardware User's Manual (W500)
Not lit.
Lit.
Not lit.
Communications
with Sysmac
Lit.
Flashing.
Not lit.
Not possible.
Possible.
A non-fatal error occurred. Refer to 5-2-2 Trou-
bleshooting Flowchart for Non-fatal Errors.
A fatal error occurred in the CPU Unit.
Refer to the NJ/NX-series Trouble-
shooting Manual (Cat. No. W503) for
the correction.
Not possible.
Studio?
Possible.

5 Troubleshooting

Power Supply Error
CPU Unit Reset
Incorrect Power Supply Unit
Connected
CPU Unit Watchdog
Timer Error
5
5-11