CIMON Ethernet PLC Link Performance Test

Test Overview

• Purpose : Measuring the data transmission delay in Ethernet PLC Link of CIMON PLC.

• Protocol : The Ethernet PLC link configured by the special program of CICON.

• Tested Module : CM1-XP3A, CM1-EC10A

• Test Period : 07th Dec. 2006 – 11th Dec. 2006

• Test Network : The network is a data link system between 13 stations. A master station has three Ethernet modules. Each of these modules served a CIMON-SCADA system, a CICON and the PLC link network. Following picture explains above network configuration.

Open

Measuring

Stn0

1. STN0 had additional two Ethernet modules for CIMON-SCADA and CICON service (Total 3 EC10As).

2. STN0 manipulated two bit flags for other PLC stations each in network. One bit for transmit (Tx bit) and another bit for received flag (Rx bit).

3. Controlled the Tx bit not to be the same state with Rx bit.

4. Measured the time span between Tx bit control and Rx bit change.

5. The average and maximum delay were calculated from above measured time span data.

6. The time span was measured by means of the 10 mSec. timer of CPU.

Stn1 – Stn12
The sequence program copied the Rx bit to Tx bit.

(Note) The Tx period of all stations are configured as 20mSec.

Measured

The measured values after 96 hours (4 days) continuous test are as follows.

• Maximum Delay : 110 – 130 mSec. (110mSec. for 11 stations, 130mSec. for 1 station)

• Average Delay : 40 – 50 mSec.

Conclusion

Above measured time delays include both two directions of data transmission. Consequently, the delay time of single direction can be induced as followings. (a half of above measured values)

• Maximum Delay : 55 – 65 mSec.

• Average Delay : 20 – 25 mSec.

Notice that this test is based on the 20mSec. transmission period. That is, above delay time cannot be necessarily the minimum delay of CIMON PLC link system. If the test was progressed under 10mSec period, the measured delay would be smaller than above.