Sampling Methods - Mitsubishi Electric MELSEC iQ-R Series User Manual

Sampling methods

The following table shows the sampling methods of data.
Sampling method
Each scan
Time specification
Trigger instruction
Precautions
When selecting "Recording Startup Trigger + File Saving Trigger" for the recording method, data is accumulated for a
specified period after a recording startup trigger is satisfied. Therefore, no data is accumulated if the sampling timing is out of
the specified period.
Sampling timing when selecting "Each Scan"
The sampling timing is as follows:
0 END
Program
Scan time
Sampling timing when selecting "Time Specification"
The sampling timing is as follows:
Ex.
The timing is set to 10 milliseconds (10 ms).
Time
specification
0
Program
Precautions
• Set the timing so that the time specification is longer than the scan time; otherwise, data is sampled during the END
processing only once if multiple sampling intervals and sampling timings for the time specification are included in one scan.
In this case, data is sampled for each scan and the operation will be the same as the each scan.
• If a sampling interval is longer than a saving period, sampled data may not be included in the saving period. In this case, a
file fails to be saved when a file saving trigger is satisfied and an error occurs in a recorder module.
A saving period differs depending on the recording method. For details, refer to the following:
Page 16 Recording methods
1 FUNCTIONS
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1.1 Recording Function
Description
Data is sampled during the END processing in a scan of a CPU module.
Data is sampled during the END processing in a scan executed first after a specified time elapses.
Data is sampled when executing the DATATRG instruction.
0
END processing Program
Scan time
Sampling
10ms
END
0
END processing Program
Scan time
END 0
END processing Program
Sampling
10ms
END
0
END processing Program
Scan time Scan time
Sampling
END 0
END processing
Scan time
Time
Sampling
10ms
END
0
END processing Program
Sampling
Time