Omron CVM1 Series, Operation Manual

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PC Link System I/O Response Time Appendix C
I/O Response Time
In these examples, the I/O response time is defined as the time required for an external input to PC Link node
0 (the polling node) to be output at node 7. The entire process includes the time required for the Link Relay bit
in node 0 to turned ON by an external input, the data to be transferred to node 7, and the output to be turned
ON by instruction execution.
In CVM1/CV-series PLCs, the operation mode can be set to synchronous or asynchronous operation. (The
default setting is asynchronous operation.) The I/O response time will vary depending on the CPU’s operation
mode.
• Conditions
Minimum I/O Response Time (in Synchronous Mode)
Minimum I/O response time = Input ON delay + Cycle time of PLC #0 + Minimum transmission time + (Cycle
time of PLC #7
×
n) + Output ON delay
The value n is as shown in the following table.
• Example Calculation
X
Node 0
Node 7
PC Link Unit PC Link Unit
Input
CVM1/CV-
series PLC
CVM1/CV-
series PLC
Output
Output
Input
Data link bit
CIO 10XX.XX
Data link bit
CIO 10XX.XX
PC Link
Number of Units in PC Link 8 Units
Number of LR bits 128 bits/Unit
Max. number of Units 8 Units
Node 0
(PLC #0)
PC Link transmission
Input
Processing
in PLC
PC Link buffer
I/O response time
Min. transmission time
Instruction
execution
Cycle
time I/O refreshing Peripheral processing
Node 7
(PLC #7)
Output
Processing
in PLC
PC Link buffer
Cycle
time
Instruction
execution
PLC model n (multiplier)
CVM1/CV Series 2
C1000H/C2000H 1
Input ON delay 1.5 ms
Output ON delay 15 ms
Cycle time of PLC #0 20 ms
Cycle time of PLC #7 50 ms
Min. transmission time 2.8 + 10 = 12.8 ms