Ethernet network of Compact Logics PLCs

Dears;

We have in our machine 10 Compact Logic PLCs which are connected via an Ethernet network. SOme time it happen that communication link break down of some of PLCs. I want to know the difference/usage of following two types of Ethernet connector RJ45 configurations; 1) T-568A Straight-Through Ethernet Cable
2) T-568B Straight-Through Ethernet Cable

We have used # 1 method for all. Attatched is a lay out of this network. Kindly assist.

Nice drawing. The details, however, appear to be on other referenced sheets. I am not familiar with some of the terms. Can you tell us the maker and part numbers for the switches? Do you have wireshark?

Wikipedia said:

http://en.wikipedia.org/wiki/TIA/EIA-568

Click to expand...

As long as all terminations are the same (568A OR 568B), it doesn't matter at all which standard you apply to Ethernet.

Traditionally, 568A was used for telecommunications systems (phones, PBX systems, etc), and 568B was implemented for purely digital (Ethernet and other twisted pair comms).

The difference is that the ORG and GRN pairs are swapped, but again, as long as all terminations are the same, it doesn't matter.

As far as your communications failures, what are the actual failures? Are they with Messaging? If so, what are the error codes, and how do you have your messaging configured ? Polled, Cyclic, cached, how many connections, etc.

Are they with produced/consumed tags?

Are they with Ethernet I/O?

It doesn't matter which wiring scheme you use, as long as you use the same on each end. T568B is what i tend to see most often though.

However, if you want to make a crossover cable, you just make one end T568B and the other T568A.

We are using AB 1783 US05T Ethernet FL Switch 5TX for panel view and PLC and AB 1783 EMS08T for combining the all.
During communication link break down problem, the numeric displays display ***** and after re-starting the panel view and some time PLC, problem removes.

In below image of Ethernet cable, you will find that Orange cable is more twisted, Blue is less and so on. What is the reason for that.