Omron NT21 Reference Manual page 433

Troubleshooting
PT Symptoms
The following System
Menu operations are not
possible.
- Establishing the
Transmit mode
- Displaying the memory
switch setting screens switch setting screens
- Screen data memory
check
- Displaying the
initialization menu
- Displaying the
calendar/time setting
screen (NT31/NT31C
and NT631/NT631C
only)
Cannot input numeric
values
Cannot input numeric
values/character strings.
Cannot operate recipe
elements using touch
switches on the PT.
Cannot change recipe
data (parameters) using
touch switch operations
on the PT.
Recipe data details are
not displayed on screen.
Window screen does not
open
Cannot switch screens
with touch switches
Buzzer sounds – cannot
use touch switches, inputs
(numeral or character
string), or recipe objects
The display is dim.
Cause
Screen Memory Protect under
Change System Setting in the
System Installer mode is set to
Disabled.
Screen Memory Protect has been
set to Disabled because the PT
power supply was turned OFF during
deletion of screen data.
The upper/lower (max./min.) limit
check for numeric value input is in
effect.
Bit 5 of the PT status control area
(numeral/character string input) is
set to 1 (ON).
Interlock bit set in the recipe
elements is OFF.
Editing of records specified in the
recipe data using the PT has been
set to disabled (the default setting)
using the Support Tool.
Specified recipe data is not set on
screen.
Bit 6 of the PT status control area
(PT window opening) is set to 1
(ON).
Bit 4 of the PT status control area
(PT screen switching) is set to 1
(ON).
The interlock function is set for the
touch switch or input field and the
controlling interlock bit is OFF.
Insufficient contrast or brightness
Backlight defective, or its life has
expired
Remedy
In the System Installer mode, set Screen Memory
Protect to Enabled. (Refer to Section 6 of the Setup
Manual.)
Do not turn the PT power OFF during deletion of
screen data.
In the System Installer mode, first change the
setting for Screen Memory Protect to Enabled, then
repeat the screen data delete operation. (Refer to
Section 6 of the Setup Manual.)
Check the screen data's upper/lower (max./min.)
limit check setting for numeric value input, and
correct it if necessary (for numeric key type, refer to
page 192; for thumbwheel type, refer to page 200).
Set bit 5 to 0 (OFF) (page 60).
Check the status of the interlock bit set in the recipe
elements and turn it ON.
Recreate the screen data with the Support Tool to
enable editing of specified recipe data, and then
send all the data in a single operation to the PT.
Recreate the recipe data on screen using the
Support Tool, and then send all the screen data in a
single operation to the PT.
Set bit 6 to 0 (OFF) (page 59).
Set bit 4 to 0 (OFF) (page 60).
Check the status of the corresponding interlock bit
and turn it ON.
For the NT31/NT31C or NT631/NT631C, use the
system menu to increase the contrast/brightness.
(Refer to section 6 of the Setup Manual.)
For the NT21, use the switches on the back of the
PT to increase the contrast. (The brightness cannot
be adjusted.)
For the NT31/NT31C or NT631C, replace the
backlight.
(Refer to section 6 of the Setup Manual.)
For the NT21, contact your nearest OMRON
representative.
Section 6-1
419