Mitsubishi Electric WS0-CPU0 - Timer Values and Logic Execution Time

Chapter 9
127
Logic programming – Function blocks
9.6 Timer values and logic execution time
The following has to be observed when selecting time monitoring functions for the
discrepancy time, synchronization time, pulse duration, muting time, etc.: The times
 have to be greater than the logic execution time,
 have a precision of +/– 10 ms in the evaluation in addition to the logic execution time.
The logic execution time depends on the number and type of the function blocks used.
It is a multiple of 4 ms. If the used logic execution time exceeds 100 %, then the logic
execution time is increased by 4 ms. The logic execution time is displayed in the logic
editor in the FB preview window. It has a precision of +/– 100 ppm (parts per million).
Effect of tested sensors
During a test signal the signal (bit) is “frozen”, i.e. the value that was present prior to
the test gap is retained for the duration of the test signal (and possibly also the max.
off-on delay). As a result a signal change can be delayed by this time, i.e. a pulse can
be longer or shorter.
9.7 Logic function blocks
9.7.1 NOT
Function block diagram
General description
The inverted input value applies at the output. If, for example, the input is High, the
output is Low.
Truth table
The following applies for the truth table in this section:
“0” means logic Low.
“1” means logic High.
Truth table for NOT
Input Output
0 1
1 0
Note
Figure 99:
Function block diagram for
the NOT function block
Table 20:
Truth table for the NOT
function block