Message Delay Times; Cs-Series, Cvm1, And Cv-Series Plcs - Omron SYSMAC CS1W-CLK13 Operation Manual

Message Delay Times

Note
Minimum Data Link I/O Response Time
9-4 Message Delay Times
9-4-1

CS-series, CVM1, and CV-series PLCs

SEND
230
Noise may increase I/O delays.
Input
Input ON delay
◆ Program
Data link I/O response time
In this case, both the input ON response time and output ON response time
are considered negligible (0), but the data processing time required for data
exchange and the time required for the data transmission itself cannot be
ignored, so they are included in the total. The respective values are as follows:
Data processing time:
0.001 × (8 + 16) × 8 + 1.7 = 1.89 ≅ 1.9 ms
Data Link transmission time:
The following formula is derived based on the transmission speed.
0.008 × (8 + 16) = 0.19 ≅ 0.2 ms
Assume that the sum of the instruction execution time and I/O refresh time for
the PLCs at nodes #1 and #7 is 1 ms. The equation for minimum data link I/O
response time is as follows:
Instruction execution time + I/O refresh time for PLC at node #1
Data processing time
Data link transmission time
Data processing time
Instruction execution time + I/O refresh time for PLC at node #7
Total (data link I/O response time)
Noise may increase I/O delays.
The two charts which follow indicate the sequence of processing which will
enable users to calculate the maximum delay time to be expected between
the time SEND(192/90) or RECV(193/98) is executed and the time the data is
stored in the remote or local node's memory area, ready for use by other
instructions in the program.
The following diagram indicates the data flow which will yield the maximum
delay time from the time SEND(192)/SEND(90) is executed by the user pro-
gram to the time the Controller Link Unit stores the data in the remote Unit's
memory.
Input device
1 cycle
PLC at node #1
Peripheral servicing interval
Data processing time
Data link transmission
Data processing time
Peripheral servicing interval
Program ◆
PLC at node #7
Output device
Output
ON delay
Section 9-4
I/O refresh
1 ms
1.9 ms
0.2 ms
1.9 ms
1 ms
6.0 ms