I/O Link Problems - Omron CJ1W-DRM21 Operation Manual

Error
The DeviceNet Unit's MS indicator is ON and
green, but the NS indicator continues to flash
green.
(The green NS indicator normally goes ON
about 2 seconds after the green MS indicator
goes ON.)
The DeviceNet Unit's MS and NS indicators are
ON and green, but the 7-segment indicator con-
tinues to flash the master's node address.
(If the slave is connected correctly, the local
node address normally goes ON within 8 sec-
onds after the green NS indicator goes ON.)
9-3-3

I/O Link Problems

Error
The I/O isn't simultaneous.
CJ-series DeviceNet Units Operation Manual for NJ-series CPU Unit(W497)
9 Troubleshooting and Maintenance
Probable cause
• If the DeviceNet Unit's 7-segment indicator is displaying an error
code, refer to the tables in 9-1 Troubleshooting with the DeviceNet
Unit Indicators.
• Restart the Unit. If operation is not restored even after the Unit is
restarted, replace the Unit.
• Check that the Master Unit's baud rate matches the baud rates set
on all of the slaves. If they don't match, set all of the baud rates to the
same value.
• Make sure that there are121-Ω terminators connected at both ends
of the trunk line. Connect 121-Ω terminators if the wrong resistance
is being used.
• Check whether all of the slaves' settings are correct.
• Check whether the communications cables are wired correctly.
• Check whether the power supply cables and power supply are wired
and set correctly.
• Check for broken wires in the communications and power supply
cables attached to the connectors.
• Check whether the slaves are operating properly.
When an OMRON DeviceNet slave is being used, refer to the
DeviceNet Slaves Operation Manual (Cat. No. W347).
When another company's DeviceNet slave is being used, refer to
that slave's user's manual.
Probable cause
Observe the following precautions when writing application programs:
• Node unit data simultaneity is ensured between the NJ-series CPU
Unit and Master Unit.
• In OMRON DeviceNet slaves, the data simultaneity of words are
ensured.
• If another manufacturer's DeviceNet slave is being used, refer to that
slave's user's manual for details.
9
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