OPC-Interface Performance

Normal Tag(Not array type)

We register the tags of the same number as the accessed point for PLC, and we measure the communication performance of SyncWrite, SyncRead,AsyncRead, AsyncWrite and DataChange.
In case of SyncWrite, SyncRead, AsyncRead, AsyncWrite, we measured the time between requesting to DeviceXPlorer from OPC Client and receiving results from it.
In case of DataChange, we measured the interval of DataChange event as DeviceXPlorer's update time is 50msec.
Communication performance is defined as average time of ten times measurement.

PC specification

OS:
    Windows 7 Ultimate  32bit OS
CPU：
    Intel(R) Core2 Duo CPU E8400 @3.00GHz 2.99GHz
Memory：2.00GB
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:Q06UDHCPU(MELSEC)
Communication Unit:F3LE01-5T
Register:D0-D8191
Max scan time:0.06msec

Communication Performance

≪Average≫

(sec)

	1	1024	2048	4096	8192	16K	32K	64K	128K
SyncRead	0.010	0.029	0.056	0.104	0.213	0.510	1.453	4.475	15.906
SyncWrite	0.011	0.119	0.212	0.417	0.852	1.741	3.644	7.925	18.585
AsyncRead	0.011	0.030	0.052	0.104	0.205	0.518	1.549	4.985	18.052
AsyncWrite	0.010	0.112	0.213	0.425	0.860	1.173	3.792	6.958	21.139
DataChange	0.060	0.060	0.060	0.119	0.148	0.310	0.636	1.276	2.604
Communication time with PLC	----	0.031	0.047	0.078	0.141	0.307	0.611	1.235	2.487

Results

In case of SyncRead/AsyncRead, it is possible to get 8,000 words per sec.
In case of SyncWrite/AsyncWrite, it is possible to get 7,000 words per sec.
In case of DataChange, it is possible to get 50,000 words per sec. It is the time as same as communication time with PLC.

Comment

*The difference of communication time with PLC and measuresing time is based on the internal-processing of DeviceXPlorer.
*You can calculate OPC-Interface processing time of other PLCs, it is to add communication time with PLC and measuring time. *You can see Other PLCs communication time in the link of the lower side.

[Jun 2010]

Array Tag

We register one array tag of the same number as the accessed point for PLC, and we measure the communication performance of SyncWrite, SyncRead, AsyncRead, AsyncWrite and DataChange.
In case of SyncWrite, SyncRead, AsyncRead, AsyncWrite, we measured the time between requesting to DeviceXPlorer from OPC Client and receiving results from it.
In case of DataChange, we measured the interval of DataChange event as DeviceXPlorer's update time is 50msec.
Communication performance is defined as average time of ten times measurement.