Omron CP1L - 12-2007, Operation Manual

Page: 117 / 673

84
Computing the Cycle Time
Section 2-7
Calculation Example
Conditions: Input ON delay 1 ms (normal input with input
constant set to 0 ms)
Output ON delay 0.1 ms (transistor output)
Cycle time 20 ms
Minimum I/O response time = 1 ms + 20 ms + 0.1 ms = 21.1 ms
Maximum I/O response time = 1 ms + (20 ms
×
2) + 0.1 ms = 41.1 ms
Input Response
Times
Input response times can be set in the PLC Setup. Increasing the response
time reduces the effects of chattering and noise. Decreasing the response
time allows reception of shorter input pulses, (but the pulse width must be
longer than the cycle time).
PLC Setup
2-7-8 Interrupt Response Times
Input Interrupt Tasks The interrupt response time for I/O interrupt tasks is the time taken from when
a built-in input has turned ON (or OFF) until the I/O interrupt task has actually
been executed. The length of the interrupt response time for I/O interrupt
tasks depends on the following conditions.
Note (1) The wait time occurs when there is competition with other interrupts. As
a guideline, the wait time will be 6 to 169
µ
s.
(2) I/O interrupt tasks can be executed during execution of the user program
(even while an instruction is being executed by stopping the execution of
an instruction), I/O refresh, peripheral servicing, or overseeing. The inter-
rupt response time is not affected by which of the above processing op-
erations during which the interrupt inputs turns ON. I/O interrupts,
however, are not executed during execution of other interrupt tasks even
if the I/O interrupt conditions are satisfied. Instead, the I/O interrupts are
Input
Input response time
Input
I/O refresh
CPU Unit
CPU Unit
Input response time
The pulse width is
less than the input
response time, so
it is not detected.
I/O refresh
Name Description Settings Default
Input constants Input response times 00 hex: 8 ms
10 hex: 0 ms
11 hex: 0.5 ms
12 hex: 1 ms
13 hex: 2 ms
14 hex: 4 ms
15 hex: 8 ms
16 hex: 16 ms
17 hex: 32 ms
00 hex (8 ms)
Item Interrupt response time Counter interrupts
Hardware response Rise time: 50
µ
s ---
Fall time: 50
µ
s ---
Software interrupt
response Minimum: 134
µ
s Minimum: 236
µ
s
Maximum: 234
µ
s + Wait
time (See note 1.)
Maximum: 336
µ
s + Wait time
(See note1.)