Appendix; Appendix 1 Processing Time - Mitsubishi MELSEC-F User Manual

APPENDIX

APPENDIX

Appendix 1 Processing Time

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 used concurrently, and how the system is configured. Use the
values obtained from the expressions below as a guideline for the processing time
when communication is performed using only one connection.
(1) Minimum processing time of communication using the fixed buffer
Data communication using binary code
Data communication using ASCII code
Data communication using binary code
App - 1
(communication between the Ethernet blocks)
(a) Communication using the fixed buffer (Procedure exist)
Tfs = St + Ke + (Kdf × Df) + Sr
Tfs : Time from the start of sending to the completion of sending
(unit: ms)
St : Sending station scan time
Ke, Kdf : Constant (see the table below)
Df : Word count of send data
Sr : Receiving station scan time
Communication using TCP/IP
Ke
12
12
(b) Communication using the fixed buffer (No procedure)
Tfs = St + Ke + (Kdf × Df)
Tfs : Time from the start of sending to the completion of sending
(unit: ms)
St : Sending station scan time
Ke, Kdf : Constant (see the table below)
Df : Byte count of send data
Communication using TCP/IP
Ke
7
[Calculation example]
Calculate the time from the start of sending to the completion of
sending (unit: ms) when the FX
and send 32 words of binary code data using fixed buffer
communication (procedure exist).
• Assume that the scan time on the receiving side is 30 ms and the
scan time on the transmission side is 25 ms:
67 (ms)
Kdf
0.0065
0.030
Kdf
0.0018
-ENET communicate using TCP/IP
3U
30 + 12 + (0.0065 × 32) + 25
MELSEC-F
Communication using UDP/IP
Ke Kdf
10 0.0069
10 0.029
Communication using UDP/IP
Ke Kdf
4 0.0014
App - 1
App