Controllogix Flex I/O Reliability -recommendation

Dear Sirs
Currently we are evaluating a PLC architecture make up for Contrologix (ENBT) and ethernet Flex I/Os.
We would like to know your recommendation, because we do not have experience with ethernet Flex I/O. We always have worked using Controlnet links.
Anyone of you knows any type of problem for the ethernet link, or disadvantages respect to controlnet?.
We would really appreciate your comments.
Kind regards
Pedro Ascencio

Pedro:
I have never user flex i/O over controlnet, recently I installed flex i/O over ethernet/IP and I got it working in less than an hour. Since then no problem, no flaw at all. My config is 1756-enbt, controllogix L61 cpu, stratix comm switch.

Dear Widelto.
Many thanks for sharing your experience.
I have seen on this web page rockwell some what it is the purpose of each network.

http://www.ab.com/networks/controlnet/faq.html

In my point of view, despite of ethernet i/o flex seems to work without a problems, it is not for control.

In my brief experience, I have used CIP protocol over ethernet (ENBT) sending messages between 2 controllers, and I have detected errors frequently. However, the link is too fast, so finally it does not affect the data transfer.

Many thanks
Pedro

To be honest with you, I used flex I/O just for digital IO´s no analog control. I have seen some friends of mine using flex I/O over devicenet with analog control and they have no problem at all.

I use 1734 Point I/O on EthernetIP to ControlLogix.
1734 Analog I/O is 14-16 bit. Flex I/O is more 12 bit.

To be honest, for new systems, I much prefer the 1734 Point I/O myself over the Flex. Both work fine with the various networks though.

I have had several strange lockup issues and module failures with Flex, and none with Point.

pedroascencio said:

Dear Sirs
Currently we are evaluating a PLC architecture make up for Contrologix (ENBT) and ethernet Flex I/Os.
We would like to know your recommendation, because we do not have experience with ethernet Flex I/O. We always have worked using Controlnet links.
Anyone of you knows any type of problem for the ethernet link, or disadvantages respect to controlnet?.
We would really appreciate your comments.
Kind regards
Pedro Ascencio

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In an industrial environment, the installation and planning of the EtherNet cable is very important.

There are some good guides on how to plan and properly install.
Go To www.odva.org and search for Publication 001480R0 EtherNet/IP Media Planning and Installation Manual.

Worked with Flex for years on RIO and ControlNet. It works fine and is reliable. The biggest problem I found is when panel-builders mash the terminal blocks together and smash the pins.

Good luck,

(8{)} .)
(Yosi)

It seems to me that R.A. is developing Point I/O more than Flex I/O.
Not saying that Flex is being discontinued anytime soon, but for the long-term I would go Point I/O.

In my point of view, despite of ethernet i/o flex seems to work without a problems, it is not for control

Click to expand...

That is a blanket statement with no merit (true 10 years go, but not now). Ethernet based fieldbuses are here to stay and are taking over the older serial fieldbuses. Ourselves, we are phasing out Profibus and going all Profinet.
Another thing is that ControlNet is in reality a standard with only 1 vendor (RA). I would be much more comfortable with Ethernet/IP which is really a standard with many vendors.

I have personally deployed FLEX hardware (Analog and HSC included on compatible networks)on pretty much every type of Master/Slave communication protocols RA/A-B has ever implemented: Universal RIO, DeviceNet, ControlNet and EtherNet/IP; custom 1794 Comm adapters are also available for ProfiBus/Net, Modbus (RTU, TCP/IP, RTU)and probably other mainstream automation protocols)
I have found it very reliable, rugged, flexible, cost effective, accurate and easy to integrate within PLC, SLC or Logix platforms.
It has a very small "footprint" (32 point DIO modules are available)and the electrical ratings are as "efficient" as they come.
One caveat that comes to my mind is absolutelly no RIUP (Removal and Insertion Under Power) especially when networked via legacy communications (EtherNet/IP seems to be oblivious to it though!)and maybe the Output modules configuration data table required "manipulation" when deployed onto legacy plaforms such as PLC or SLC.

Flex I/O is more robust that Point I/O. My company has put both under IEEE C37.90.1 surge withstand testing and Flex is much more durable.

I would recommend using 1756-EN2T or EN2TR (depends on if you are using a star network, or a ring) over the 1756-ENBT.