Omron NT11 - 01-2004 User Manual page 150

Troubleshooting
NT11 Symptoms
The memory table display
contents differ from the ini-
tial value set at the NT
Support Tool.
Updating of numeric val-
ues and text is delayed.
Some of the elements
arranged on a normal
screen are not displayed.
The following System
Menu operations are not
possible.
- Establishing the Transmit
mode
- Displaying the memory
switch setting screens
- Screen data memory
check
- Displaying the initializa-
tion menu
Cannot input numeric val-
ues.
The display is dim.
The display is too faint.
The digits in numeral dis-
play come out as *.
Cause
Since the memory table entry is allo-
cated to the host memory, the display
is updated in accordance with the
contents of the host memory.
Malfunction due to external noise
There are too many numeral/text dis-
plays on the displayed screen.
The cycle time is extended due to
heavy processing at the host.
In an RS-422A/485 connection, there
is illegal branching or an erroneous
terminator setting.
The quantity of read data exceeds the
stipulated restriction.
The total of the element coefficients
for the displayed screen is greater
than 1024.
Screen Memory Protect has been set
to Disabled because the PT power
supply was turned OFF during dele-
tion of screen data.
The upper/lower (max./min.) limit
check for numeric value input is in
effect.
The contrast setting is too low.
Backlight defective, or its life has
expired.
The contrast setting is too high.
The number of digits of a numeric
value in a numeral memory table
entry exceeds the set number.
Remedy
When the contents of the memory table entry are set
as a fixed values, do not allocate the memory table
entry to the host memory.
Carry out grounding work in accordance with the
conditions by referring to 2-2-3 Wiring the Ground
Wire, page 21.
Reduce the number of numeral/text displays on the
screen for which updating is delayed.
Shorten the host cycle time.
Wire correctly by referring to SECTION 2 Hardware
Settings and Connections.
Check the maximum number of elements. Create the
screen data again and then transmit all of the screen
data in a batch to the NT11.
Do not turn the PT power OFF during deletion of
screen data.
Check the screen data's upper/lower (max./min.) limit
check setting for numeric value input, and correct it if
necessary. Refer to 4-6 Numeral Setting.
Increase the contrast with the contrast adjustment on
the back of the NT11.
Contact your OMRON service center. (The backlight
cannot be removed.)
Reduce the contrast with the contrast adjustment on
the back of the NT11.
• Confirm the values of the PLC words allocated to
the numeral memory table entry.
• Allocate one PLC word to each numeral memory
table entry.
Section 6-1
137