Appendices; Appendix 1 Processing Time - Mitsubishi Electric MELSEC-L SERIES Basic User Manual

APPENDICES

Appendix 1
Calculate the minimum processing time for each function using the expressions below. Note that the processing time
may become longer depending on the load factor on the network (how congested the line is), the window size of each
connected device, the number of connections, and system configuration. Use the values obtained from the
expressions as a guideline for the processing time when communications are performed in only one connection.
(1) Minimum processing time of communications using a fixed buffer
(communications between the E71s)
(a) Procedure exists
Tfs = St + Ke + (Kdf  Df) + Sr
Tfs
St
Ke, Kdf
Df
Sr
Item
Communications using a binary code
Communications using an ASCII code
(b) No procedures
Tfs = St + Ke + (Kdf  Df)
Tfs
St
Ke, Kdf
Df
Item
Communications using a binary code
[Calculation example]
The time between the E71 sending 1017-word data of a binary code and it completing the sending when the
E71 communicates with another E71 in TCP/IP with the "Procedure Exist" method (unit: ms)
Assume that the scan time on the sending side is 10ms, and the scan time on the receiving side is 8ms.
• 28.6561 (ms)  10 + 7.3 + (0.0033  1017) + 8
304
Processing Time
The time from the start of sending to the completion of sending (unit: ms)
Sending station scan time
Constant (Refer to the table below.)
Number of send data words
Receiving station scan time
The time from the start of sending to the completion of sending (unit: ms)
Sending station scan time
Constant (Refer to the table below.)
Number of send data bytes
LJ71E71-100
TCP/IP communications
Ke Kdf
7.3 0.0033
7.3 0.0082
LJ71E71-100
TCP/IP communications
Ke Kdf
5.4 0.0010
UDP/IP communications
Ke Kdf
6.2 0.0040
6.2 0.0081
UDP/IP communications
Ke Kdf
3.8 0.0009