Message Service Transmission Delay - Omron Sysmac NJ-series User Manual

14 Communications Performance and Communications Load

14-4 Message Service Transmission Delay

This section describes the delay time that occurs in CIP communications instruction (CIPWrite) service
processing.
Instruction (CIPWrite) executed.
OI UPG MC
Controller#1
System
service
Transmission path
Controller#2
Received command interpreted.
Transmission
System
delay
service
Task period
(local node)
Maximum transmission delay time = Send delay + System service execution time + Transmission delay + Receive delay + System service execution time
+ Variable write time + System service execution time + Transmission delay + Receive delay + System service execution time
(Remote node task period)
Processes that cause a delay time are processed in the task periods at each node as shown in the
above diagram. Line-based delays are as follows:
 Transmission Delay
The transmission delay on an Ethernet line is 50 μs or less. This delay time can be ignored.
14-28
IO UPG MC
Command generated.
Line
×
IO UPG MC IO UPG MC
System System
service service
Transmission System System
Receive Variable
service service
delay
delay written.
Line
Task period Task period
(remote node) (remote node)
(Local node task period)
NJ/NX-series CPU Unit Built-in EtherNet/IP Port User's Manual (W506)
Instruction completed.
OI UPG MC OI UPG MC
Received response interpreted.
System
service
×
Line
Variable written.
Response generated.
Transmission System
Receive
service
delay
delay
Line
Task period
(local node)
(Local node task period)
(Remote node task period)