Mitsubishi Electric MELSEC iQ-R Series User Manual page 300

Period during which devices and labels can be saved
A period during which devices and labels can be saved is calculated with the following formula:
Saving possible period (second) =   (  )    471,859.2
A saving possible period calculated with this formula is an approximate value because the rate of change and sampling
interval vary depending on the program and operating status.
The following table shows the details of each variable in the calculation formula.
Varia Item
ble

Recording buffer capacity [MB]

Sampling size [word]
 Rate of change
 Sampling interval [second]
*1 The minimum saving possible period (approximate value) can be calculated by calculating the rate of change as 1.
*2 When selecting "Time Specification" for the sampling method, the sampling interval for devices and labels will not be shorter than the
scan time. Set a value greater than or equal to the scan time for the sampling interval for calculation.
*3 When selecting "Trigger Instruction" for the sampling method and executing a trigger instruction once per program execution, the saving
possible period (approximate value) can be calculated by calculating the sampling interval as the scan time.
Ex.
For calculating the saving possible period under the following conditions:
 Recording buffer capacity: 400 MB
 Sampling size (overall): 10,000 words
 Rate of change: 0.3
 Sampling interval: 100 ms
Saving possible period (second):
Ò Ó Ô
400 ÷ ( 10,000 × 0.3
APPX
298
Appendix 3 Processing Time
Details
The buffer capacity for devices and labels accumulated by a recorder module/camera recorder module.
It can be set in the module parameter of a recorder module/camera recorder module.
The size of all sampling targets set in the recording setting.
It can be checked in "Sampling Size (Overall)" in the "Recording Setting" screen.
The rate of values of sampled devices and labels that have changed since the last sampling.
It is 1 when all values of devices and labels to be sampled are assumed to change per sampling, and 0.5
when half of them are assumed to change.
It is calculated with the following formula:
Rate of change = Size of changed data  Sampling size (overall)
The sampling interval for devices and labels.
It differs depending on the sampling method.
• Each scan: Scan time
• Time specification: Sampling interval set in the recording setting
• Trigger instruction: Execution interval of a trigger instruction
• Safety cycle time: Safety cycle time for executing a safety program
Õ
) × ( ) × 471,859.2
100 × 0.001
*1
≈ 6,291.5(seconds)
*2
*3