User manual

Troubleshooting and Further Information
156
33003962 11/2011
Troubleshooting
Overview
Condition Cause Remedy
????? displayed rather
than any values
The transmission parameters set in the
Vijeo-Designer Lite software for the
protocol you are using for communication
are not configured correctly.
Check the transmission parameters in the
dialog box of the Vijeo-Designer Lite
software for the protocol you are using.
For more detailed information refer to the
user manual of this protocol.
No memory allocation for this variable has
been declared in the PLC
Allocate memory space for the variable
The equipment declared for the variable
does not exist
Modify the list of equipment and check the
declared addresses
The equipment is not connected to the
terminal
Check the connection
The equipment is connected to the
terminal via an XBT Z978 cable
Check the connection. Try using an
XBT Z9780 cable
The equipment is connected to the
terminal via an XBT Z9780 cable
Check the connection. Try using an
XBT Z978 cable (equivalent to an
XBT Z9780 cable equipped with an
XBT ZN999 adaptor).
Cannot read dialog
table message displayed
on terminal
The equipment declared for the dialog
table does not exist
Modify the list of equipment and check the
declared addresses
No memory allocation for the dialog table
has been declared in the PLC
Allocate memory space for the dialog
table in the PLC (e.g., %MW100 to
%MW125)
The equipment is not connected to the
terminal
Check the connection
Incorrect dialog table
authorization message
The value of the authorization word
stored in the PLC is not correct
Using Vijeo-Designer Lite, check the
expected value (\Configuration\Dialog
Table) for the Authorization Table and its
location in the memory equipment
Product seems to be not
powered (backlight not on
and nothing displayed on
the display unit
XBT N401/NU400: No 24 V power supply Check the power supply
XBT N200/400:
z No power supply via the PC mouse
port.
z Dialog table forces the back-light to
remain off.
z No power supply via the PLC
communication port in run mode.
Check whether the PC mouse port has
been activated (see PC Control Panel),
check the PLC program. Check whether
the cable is connected to the PLC port.
Check that power is being supplied to the
PLC.