Communications Load - Omron CJ1W-EIP21 - 10-2010 Operation Manual

Communications Performance and Communications Load
This section describes the communications performance in an EtherNet/IP network, and shows how to estimate the I/O
response times and transmission delays.
10-1 Communications System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-1-1 Tag Data Link Communications Method . . . . . . . . . . . . . . . . . . . . .
10-1-2 Calculating the Number of Connections. . . . . . . . . . . . . . . . . . . . . .
10-1-3 Network Transmission Delay Time . . . . . . . . . . . . . . . . . . . . . . . . .
10-2 Adjusting the Communications Load . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-2-1 Checking Bandwidth Usage for Tag Data Links . . . . . . . . . . . . . . .
10-2-2 Tag Data Link Bandwidth Usage and RPI . . . . . . . . . . . . . . . . . . . .
10-2-3 Adjusting Device Bandwidth Usage. . . . . . . . . . . . . . . . . . . . . . . . .
10-2-4 Changing the RPI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-2-5 RPI Setting Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-3 I/O Response Time in Tag Data Links . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-3-1 Timing of Data Transmissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-3-2 EtherNet/IP Unit or CJ2H Built-in Port Data Processing Time . . . .
10-3-3 Effect on the CPU Unit's Cycle Time. . . . . . . . . . . . . . . . . . . . . . . .
10-3-4 Tag Data Link I/O Response Time Calculation Example. . . . . . . . .
10-4 Tag Data Link Performance for CJ2M Built-in EtherNet/IP Ports . . . . . . . . .
10-4-1 Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-4-2 Tag Data Link I/O Response Time . . . . . . . . . . . . . . . . . . . . . . . . . .
10-5 Message Service Transmission Delay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10-5-1 Maximum Transmission Delays (Excluding Delays in the Network)
SECTION 10
262
262
264
265
268
269
270
271
272
276
283
283
283
284
285
291
291
292
294
294
261