Rockwell Automation 1772-LP3 PLC - 2/30 Programmable Controller Programming and Operations Manual - Manual (Page 121)

Timer and Counter Instructions
Chapter 5
5Ć23
As an example, we will calculate the execution time for File-to-File move
in the distributed complete mode for the following conditions:
Rate per scan = 256 words operated upon per scan.
File length = 542 words
542 words in file = two full 256 word blocks + 30 words. Therefore, use
2 for the number of blocks operated upon per scan and ignore the +30
words.
Therefore: Time = 85 + 6.8(256) + 14.4(2)
Time = 85 + 1741 + 28.8 = 1855 microseconds
The incremental mode requires an execution time of 62 microseconds.
When false, the File-to-File move and File Complement execution time is
6 microseconds. The first scan the rung is false after the done bit is set
requires 17.6 microseconds to reset flags and counters.
Table 5.F
Average Execution Times For FileĆtoĆFile Move and File Complement
Instructions
Time (Microseconds)
Rate (Words per Scan) Dist. Complete Mode Complete Mode
ăă5
ă10
ă15
ă25
ă50
100
256
512
ă119
ă153
ă187
ă255
ă425
ă765
1840
3595
ă101
ă135
ă169
ă237
ă407
ă747
1822
3578
Formulas for more exact approximations can be found in Section 5.6.3.
Incremental mode requires 62 microseconds per scan. When FALSE, the execution time is 6 microseconds. To reset flags and
counters requires 17.6 microseconds.
Table 5.G presents average instruction execution times for the logic
instructions File-to-File AND, OR, XOR.
The execution time, T, in microseconds for the distributed complete mode
is given by the equation:
T = 125 + 9.8(Number of words operated upon per scan) + 14.4
(Number of 256 word blocks operated upon per scan)
5.6.4
Logic Instructions
FileĆtoĆFile AND, OR, XOR