Checking The Processing Time; Checking The Data Logging Processing Time - Mitsubishi Electric MELSEC-L Series User Manual

10.2

Checking the Processing Time

Data logging is the best-effort type
*1 The concept of obtaining the maximum performance from the condition at the time
Logging may not be performed at the specified sampling intervals because processing time may vary depending on
the configuration or other connected devices. After configuring the system, thoroughly examine the processing time
before starting the system operation.
The following figure shows the process from data collection to file output.
This section also describes what is the point when checking the time required for the following processing.
Processing
Stores the data accumulated in the buffer to a data logging file.
If the data logging processing cannot keep up with the speed of
1) Data logging processing
the sampling processing, a processing overflow occurs and
some data will be missing.
10.2.1

Checking the data logging processing time

Check that all the data sampled by data logging (continuous logging) have been processed. The following shows the
information to be checked and corrective action to be taken if an error is detected.
Information to be checked
Check the value in the special register (Processing timeout count).
(If the special register value is other than "0", the data logging
processing (file saving) does not keep up with the processing speed of
the target data.)
For the numbers of the special register, refer to Page 147, CHAPTER 12.
*1
function.
CPU module
Buffer
Device
Data
Description
Perform any of the following:
• Increase the sampling interval. (
• Reduce the number of sampled data. (
• Increase the buffer capacity. (
• Decrease frequency of file switching. (
Check the following after taking a corrective action.
• The value in the special register (Processing timeout count) is "0".
• The value in the special register (Free buffer space) does not drop to near "0" with
1)
Data logging
Check point
Check that all the data sampled
have been processed.
Corrective action
time.
CHAPTER 10 PROCESSING TIME
Reference
Page 143, Section 10.2.1
Page 99, Section 8.4.4)
Page 101, Section 8.4.5)
Page 115, Section 8.5.2)
Page 109, Section 8.4.10)
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