Appendix 5 Processing Time; Transmission Delay Time - Mitsubishi Electric MELSEC iQ-R Series User Manual

Appendix 5

Transmission delay time

The following describes the formulas used to calculate the transmission delay time of EtherNet/IP communications.
Note that the processing time may be prolonged depending on the load ratio of the network (degree of line congestion), the
processing performance of controllers, and the system configuration.
Class1 communication transmission delay time
The following describes the concept and the calculation formula of the transmission delay time of Class1 communications.
■Concept of send delay time
CPU module
RJ71EIP91
EtherNet/IP device
No. Item name
(1) Sequence scan
(2) Module processing time
(3) RPI
■Concept of receive delay time
EtherNet/IP device
RJ71EIP91
CPU module
No. Item name
(1) Sequence scan
(2) Module processing time
(3) RPI
■Calculation formula of transmission delay time
Calculation value Calculation formula (Unit: ms)
0.573 + (sequence scan ÷ 2) + module processing time
Normal value
Maximum value 0.725 + sequence scan time + module processing time
*1 Calculate the module processing time using the following formula.
Module processing time[ms] = 0.0001 × Total data size[byte] + 0.007 × number of connections
Processing Time
(1)
(2)
(3)
Description
Time required from setting the send data in a program to refreshing the buffer memory on the
RJ71EIP91.
Time required for transferring send data from the buffer memory on the RJ71EIP91 to the send
buffer.
RPI setting value (transmission interval time)
(3)
(2)
Description
Time required for refreshing the receive data from the buffer memory on the RJ71EIP91 to a
program.
Time required for transferring receive data from the receive buffer to the buffer memory on the
RJ71EIP91.
RPI setting value (transmission interval time)
(1)
*1
+ (RPI ÷ 2)
*1
+ RPI

Appendix 5 Processing Time

A
APPX
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