Chapter 15 Troubleshooting 15-1 To - Hitachi HIDIC EH-150 Applications Manual

Chapter 15 Troubleshooting
Phenomenon
No
communication
No input
No output
• No communication
In this status, neither the MS nor the NS LED are lit in green
each module turned on?
power supply turned on?
Is the connector tightened
Is the communication cable
connected properly?
the same for all the devices
resistors placed on both ends of
Is the network length within
the communication power supply
Is the scan list registered?
Replace faulty parts if spare parts are
available.
Contact Hitachi's Service Dept .
Table 15.1 Main phenomenon
Incorrect setting of the communication speed, node address
overlap, improper fitting of connector, cable breakage,
power supply voltage error
Scan list not registered, Illegal IO addressing
Scan list not registered, Illegal IO addressing
Is the power supply of
YES
Is the communication
YES
securely?
YES
YES
Is the baud rate
on the network?
YES
Are the terminal
the trunk line?
YES
the specifications?
YES
Is the voltage of
normal?
YES
YES
Main cause
NO
Turn on the power supply of each module.
NO
Turn on the communication power supply.
NO
Tighten the connector securely.
NO
Set the communication cable properly.
NO
Make sure the baud rate is set accordingly.
NO
Attach termination resistors.
NO
Fit the network length within the specifications.
NO
Examine the position of the communication power
supply again.
NO
Register from the configurator.
15-1
Chapter 15 Troubleshooting