Rockwell AB Communication performance

ControlLogix series Ethernet communication

Add array OPCItems as Advise from a OPC Client.
It is measured reading time from added OPCItems. Communication performance is defined as average time of ten times measurement.
This time means to read the value of a continuous area of the device.

PC specification

OS:
    Windows 7 Professional  32bit OS
CPU：
    Intel(R) Core(TM) i7 CPU 860 @2.80GHz
Memory：3.00GB
OPC Server：
    DeviceXPlorer OPC Server Ver4.2.0.2
OPC Client：
    OPCClient sample VcSampleOpc(C++)
Cable：
    100BASE-TX cross cable connecting directly

OPC Server setting

Protocol Timer Tick：10msec
Timer Tick for Async Update Mode：10msec
Multi Access Mode：Enable
Multi Access for Snyc Asnyc：Disabled
Async Update Mode：Disabled

PLC setting

CPU:Logix5561
Communication Unit:EtherNet/IP
Device：IntArray[0]-IntArray[16383]
Max scan time:1.6msec

Communication Performance

(sec)

	1024	2048	4096	8192	16K	32K	64K	128K
Average	0.078	0.141	0.281	0.546	1.076	2.168	4.352	8.735
Max	0.078	0.141	0.281	0.546	1.077	2.169	4.353	8.736
Min	0.078	0.141	0.281	0.546	1.076	2.168	4.352	8.721

Results

In case of continuous integer array tag , it is possible to get max 15,000 points per sec.

Commnets

*Graph displays average time of ten times measurement.(1point = 1word)
*In case of 32K points access , Read 32K points by using 2 devices.( 16Kpoint per 1 device).
*The result only means our examination, it doesn't guarantee performance.

[Jun 2010]