Omron CJ2H-CPU6 - REV 02-2010, Руководство по эксплуатации, Страница: 326 / 464

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Message Service Transmission Delay Section 10-5
Example Calculation In this example, RECV(098) is used to receive 256 words of data from another
PLC. The maximum transmission delay is calculated based on the following
operating conditions.
• Local node’s CPU cycle time: 10 ms
• Local node’s CPU execution mode: Normal
• Local node’s CPU peripheral servicing time: Default (4%)
• Remote node’s CPU cycle time: 15 ms
• Remote node’s CPU execution mode: Normal
• Remote node’s CPU peripheral servicing time: Default (4%)
• Baud rate: 100Base-TX
Item Calculated value
CPU Bus Unit service cycle (local
node, 1) 10 ms
CPU Bus Unit service processing
time (local node, 1) 0.4 ms
Send processing (command) 0.550 ms
≅
0.5 ms
Transmission delay (command) 0.0118 ms
≅
0.1 ms
Receive processing (command) 0.704 ms
≅
0.7 ms
CPU Bus Unit service cycle (remote
node) 15 ms
CPU Bus Unit service processing
time (remote node) 0.6 ms
Send processing (command) (256
×
0.002) + 0.550 = 1.062
≅
1.1 ms
Transmission delay (command) (256
×
0.0013) + 0.0118 = 0.3446
≅
0.3 ms
Receive processing (command) (256
×
0.003) + 0.704 = 1.472
≅
1.5 ms
CPU Bus Unit service cycle (local
node, 2) 10 ms
CPU Bus Unit service processing
time (local node, 2) 0.4 ms
Maximum transmission delay 10 + 0.4 + 0.5 + 0.1 + 0.7 + 15 + 0.6 + 1.1 +
0.3 + 1.5 + 10 + 0.4 = 40.6 ms