Hitachi HIDIC EH-150 Applications Manual page 33

Chapter 8 Troubleshooting
Trouble
The ERR LED is lit even if the
communication seems to work fine.
A slave does not get on-line even if the
slave is configured in the master.
A slave does not react on a command
from the PLC even if everything is
configured correctly.
Possible cause
All nodes that are configured in the
master are not present on the network.
Node address in configurator does not
match the actual node address.
Wrong offset address is used in the
PLC program for the specific slave.
8-1
Chapter 8 Troubleshooting
Action
Connect all nodes to make the ERROR LED
turn off. Communication is running on nodes
that are present in the network even if the
ERROR LED is lit.
Check the node address on the slave.
Check the input and output offset addresses
in the configurator to make sure that the
right address is used.