Omron Programmable Terminals NT31 NT31C Setup Manual page 243

Troubleshooting
NT31/NT31C Symptoms
The graph display does
not change.
The trend graph display
does not agree with the
actual time axis.
The Programming
Console function cannot
be used.
The Device Monitor
function cannot be used.
The memory table display
contents differ from the
initial value set at the
Support Tool. pp
Cause
One of the percentage display
settings — −100%, 0%, or 100% —
is incorrect.
The cycle for graph display update
processing is longer than the set
sampling cycle.
The communication settings are
incorrect.
A Programming Console is
connected.
The PC does not support the
Programming Console function.
The system program for other
vendor's PCs has been installed.
(PC models other than OMRON.)
The communications settings are not
correct.
The PC does not support the Device
Monitor function.
The system program installed in the
PT is for a PC maker other than
OMRON.
Since the memory table is allocated
to the host memory, the display is
updated in accordance with the
contents of the host memory.
The battery voltage has dropped and
the data in the memory table has
been destroyed.
Since ON is set for the resume
function, the initial values of the
screen data memory are not written
to the memory tables.
The numeral memory table is
specified as the destination for a
mathematical table's results.
Remedy
Set the −100%, 0%, and 100% values in the
following relationship:
−100% value < 0% value < 100% value
Delete other elements on the same screen as the
trend graph that are allocated to the host and have
a high update frequency. Or lengthen the sampling
cycle.
Set the communication method as follows when
using the Programming Console function.
S With C-series PLC: 1:1 NT Link
S With CS1-series PLC:
1:N NT Link (standard or high-speed)
It is not possible to use a Programming Console and
the Programming Console function at the same
time. Disconnect the Programming Console.
Not all PCs support the Programming Console
function. Check the model of PC you are using.
(6-12 Programming Console Function, page 221)
The Programming Console function can be used
only when the system program for OMRON PCs is
installed. Install the correct system program.
Set the communication method as follows when
using the Device Monitor function.
S With C-series PLCs: 1:1 NT Link or 1:N NT Link
S With CS1-series PLCs:
1:N NT Link (standard or high-speed)
Not all PCs support the Device Monitor function.
Check the model of PC you are using. Refer to 6-13
Device Monitor Function for details.
The Device Monitor function can be used only when
the PT is connected to a PT with the system
program for OMRON PCs installed. Install a system
program that supports the Device Monitor function.
When the contents of the memory table are set as a
fixed value, do not allocate the memory table to the
host.
Replace the battery and execute memory table
initialization. (7-3-1 Replacing the Battery, page 244,
and 6-4-5 Initializing the Memory Tables, page 147)
Execute memory table initialization. (6-4-5
Initializing the Memory Tables, page 147)
If the resume function does not need to be used,
use the NT31/NT31C with the resume function OFF.
(6-9-10 Setting the Resume Function, page 181)
Calculations are executed continuously while the PT
is operating and the calculation results are
automatically written to the memory table. Specify
another numeral memory table or a word in the
host.
Section 7-1
233