Checking Sampling Process Time - Mitsubishi Electric MELSEC iQ-R Series User Manual

Checking sampling process time

Check if the processing to sample data from the CPU module is operating in the specified data sampling interval.
Checking the I/O signals, and the processing method when a problem occurs are as follows:
For high speed sampling
I/O signal
High Speed Sampling Failure' (X1A)
if ON
Unable to sample data in the specified data
sampling interval (each scan, time
specification).
*1 Number of windows executing the real time monitor in GX LogViewer.
■Considerations
Data is sampled at the END processing of sequence scan.
Therefore, data sampling is delayed for the specified sampling interval. (In this case, 'High speed sampling failure' (X1A) does
not turn ON.)
For general sampling
I/O signal
'General sampling delay occurrence' (X1E)
if ON
A delay occurred compared to the specified
data sampling interval.
■Considerations
If a delay within the allowed time for general sampling delay occurs, 'General sampling delay occurrence' (X1E) will not turn
ON.
The initial value of the allowed general sampling delay time is half of the shortest sampling time among data logging, event
logging, or report setting in which the general sampling is specified.
The allowed general sampling delay time can be changed in 'Allowed general sampling delay time' (Un\G804 to 805).
APPX
350
Appendix 7 Processing Time
Handling method when a problem occurs
Change the settings such that the following conditions are satisfied.
Each sequence Change the number of settings in which the high speed sampling is specified, or set the
scan constant scan to the CPU module.
• Sequence scan time (milliseconds) > (0.5  number of specified settings for high speed
sampling + 2.0  number of real time monitors
Time specification Change the number of the specified settings for high speed sampling, or set the sampling
interval.
• Sampling interval (milliseconds) > (0.5  number of specified settings for high speed
sampling + 2.0  number of real time monitors
Handling method when a problem occurs
Take any of the following actions.
• Reduce the number of specified settings for general sampling.
• Decrease the amount of sampled data.
• Organize the data logging setting, event logging setting, and report setting per access target CPU. (When
data from multiple access target CPUs is mixed in a single data logging, event logging, or report setting,
sampling takes time.)
• Mount a high speed logger module in the access target CPU station and execute high speed sampling.
*1
)
*1
)