KEYENCE KV Series - Manual (Page 124)

Chapter 3 Simulator
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Setting the scan time
Settings ➔ Scan Time
Set the time for execution of one scan or step. For execution of one scan, there are
two time settings: the measured value indicating the actual time and the virtual fixed
value (fixed scan). (For execution of one step, only the virtual fixed value can be
set.)
1. Select "Scan Time" from the "Settings" menu.
The "Set Scan Time" dialog box is displayed.
2. When setting the fixed scan, click "Set Fixed Scan" to add a check mark.
3. Set the scan time to a value between 0 and 5,000 msec. The default value is set
to "10 msec" for execution by step, or set to the actual required time for execution
by scan.
4. Click the [OK] button to save the displayed value. To cancel the setting, click the
[Cancel] button.
■ Fixed scan
The length of the scan time while the simulator is running usually depends on the
personal computer’s processing speed. When the fixed scan mode is selected,
simulation can be performed in a scan time equivalent to that processed virtually on
the PLC side. Use this function to perform simulation of a program in which scan
time is important.
Setting the watch dog timer
Settings ➔ Set Watch Dog Timer
The watch dog timer detects abnormal delays in the program execution cycle. These
delays can be due to programming errors (i.e. infinite loops), or any other condition
that may cause the program to take too long to finish. The default value is "3,000
msec (= 3 sec)".
When the scan time exceeds the preset value of the watch dog timer plus the wait
time, a watch dog timer error occurs.
To set the watch dog timer, perform the following procedure.
1. Select "Set Watch Dog Timer" from the "Settings" menu.
The "Set Watch Dog Timer" dialog box is displayed.
2. Enter the watch dog timer within the range of "500 msec (0.5 sec) to 5,000 msec
(5 sec)".
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