7-2SectionResponding to Displayed Error Messages
235
NT31/NT31C Symptoms RemedyCause
The display is dim. Insufficient contrast or brightness Increase the contrast/brightness (pages 191 and
193).
Backlight defective, or its life has
expired
Replace the backlight (page 242).
The display is too faint. The contrast is too high. Reduce the contrast (page 191).
The digits in numeral
display come out as *.
The number of digits of a numeric
value in a numeral memory table
exceeds the set number.
• Confirm the values of the PC words allocated to the
numeral memory table.
• Allocate one PC word to each numeral memory
table.
”**” or ”***” is displayed
in the numeral display or
numeral input field.
The numeric value in the numeral
memory table exceeds the number
of display digits.
• Check the values of the PC words allocated to the
numeral memory table entry.
• Allocate only one word to each numeral memory
table entry if the numeral display or numeral input
field has 4 digits or less.
7-2 Responding to Displayed Error Messages
When the NT31/NT31C displays an error message, find the corresponding
symptoms in the appropriate table below and respond by following the Remedy
indicated in the table.
For details of the error messages displayed when using memory unit and correc-
tive action to take for them, refer to 3-5 Using a Memory Unit (NT31/NT31C with
Vj) in page 39 or 3-6 Using a Memory Unit (NT31/NT31C without Vj) in page
47.
7-2-1 Errors Occurring at Start of Operation and Their Remedies
The table below shows the errors that can occur when the power to the
NT31/NT31C is turned ON and when operation starts, and their remedies.
Message Cause Remedy
[No Comm. Protocol]
Set the comm. Protocol by
MAINTENANCE MODE.
No communication protocol has
been set.
Communication protocol and
screen data type are mismatched
Using the memory switches, set the
communication method to be used for
communication with the host. (6-7 Setting
Conditions for Communications with Host
by Using Memory Switches, page 157)
[Screen Data Error]
Screen Data corrupted.
Initialize Screen Memory, and download
Screen Data again.
- The power was switched OFF
during screen data
initialization, checking, or
transmission.
- Transmission of screen data
was interrupted.
- Illegal data has been written to
the screen data memory.
Initialize the screen data memory by
operation at the System Menu, then
re-transmit the screen data. (6-4-1
Clearing Screen Data, page 140)
If the problem persists, contact your
OMRON service center.
[No Screen Data]
No Screen Data is saved in Screen
Memory.
Download Screen Data using by the
Support Tool.
Then set the PT to the TRANSMIT
MODE, and download Screen Data
again.
No screen data is registered. Transmit screen data from the Support
Tool.