HMI w/ integrated PLC Opinions

I am currently looking into standardizing my companies control options; given the simplicity and redundancy of our systems i feel like a PLC/HMI combo might be a good route.

However, I am drowning in the options available. When selecting controllers previously it was quite simple as we always spec'ed AB for US customers or Siemens or IDEC for Int'l. However the task for this product line is all about getting standardization set and costs down so its wide open to the best product for the job.

Does anyone have any feedback on the options out there? Must be robust hardware as the systems will be on ocean going ships and oil rigs. Also must have Ethernet for remote IO and COMs.

Thanks!

Shawn,

Obviously the first thing to look for is software support.

That being said for smaller jobs around here I have been using Unitronics. They are a HMI and PLC in one, and you can add different I/O, comms cards, and IMHO were really easy to start using.

The software is free, and comes with the software and a cable in every box.

Oh yeah, they are cheap as well as robust.

Cheers

Mark

A couple of things I dislike about integrated PLC/HMI devices:

PLCs have often very long system lifetimes. For example a Siemens 315 CPU has existed in the current generation (the one with the MMC card) for 12 years. New versions have come many times, but they are backwards compatible so that you can exchange a defective CPU for a new one without having to convert the program. Install the old program flash card in the new CPU and it will run. I am certain that you can get a compatible CPU even 10 years from now.
In the same period of time I have seen several HMI generations come and go. And each time a new generation is launched, you have to "migrate" the HMI program.

The hardware of PLCs lasts much longer than the hardware of HMIs.
The HMIs achilles heel(s) are the buttons that wear out, and the display that go dim or totally fail.

With separate PLCs and HMIs, you can put together the combination that suits your requirements best.
Maybe you need a very powerful PLC, but a very basic HMI. Or maybe the other way around.
With integrated PLC/HMIs you can only choose from what the manufacturer has decided for you.

IMHO opinion, you wont get any standardization benefit from going this route.

Thanks, Jesper;
That sums up my experience with integrated PLC/HMI combos too.
Siemens has stopped production of its C7 line exactly because of such issues.
Regards,
Daniel Chartier

shawnhimself said:

When selecting controllers previously it was quite simple as we always spec'ed AB for US customers or Siemens or IDEC for Int'l.

Click to expand...

Why not just stick to one brand world-wide; I'm probably biased having used AB almost exclusively for the past 30 years so that is my preferred brand. I work mainly in Europe both on and offshore but have also worked in the Middle East and Kazakhstan and never had a problem with AB. I've used most of their PLC's but specialise in drives (both LV and MV), AB drives and PLC's are used extensively in the offshore industry and on board ships, if that is where most of your work lies then I would suggest sticking with one of the big well known brands.

The only slight issue I've had with AB support was with Modbus comms to an AB drive from a Telemecanique PLC when working in Paris and not speaking French but once I got my head around how the AB modbus module worked it was fine.

I'm sure you will get similar support from the other big players worldwide but I would first pick a brand you are happy to use and has proven reliability then as someone else said check up on the support.

Yeah... I had the same concerns regarding having one component fail prior to the other.

The reason I even looked at this route is : cost and space savings. I'm dealing with the age old issue of design engineers wanting squeeze my panels into a small dark corner of the machine.

Shawn,

The challenge with standardizing is dependent upon your market and customer requirements.

One approach that I have used for many years is the embedded PLC route. It doesn't look like a traditional PLC, therefore you don't call it a PLC and are able to standardize upon one hardware solution. There are other advantages of an embedded PLC over a traditional PLC or even an "all in one" solution that we can discuss further, if you are interested.

Much will depend upon your application requirements and which product ultimately fits your requirements the best.

As a distributor, we offer a solution that incorporates Triangle Research for Ethernet embedded PLCs and KEP for touch screens.

http://www.eternity-sales.com/tri-plc/tri-plc.htm
http://www.eternity-sales.com/KEP/MMI8000.htm

If this approach interests you, feel free to respond to this post, pm me, or use the link provided in my signature to email me your requirements to review and ultimately present a solution that will be beneficial to your company and customers.

Our synergy section provides you with some additional insight regarding how we approach our customer's requirements.

http://www.eternity-sales.com/synergy_home.htm

As stated previously, my first reaction would be to leave the HMI and control portion seperate. Their techs. seem to progress at different rates. That being said, I've used the Horner 'all in one' with their block (SmartStax?) I/O. The HMI was good, PLC OK (very much like a GE). The PLC programming software was not too hot but that may have improved by now. The I/O was very compact but a real pain to work on for troubleshooting.

If these machines aren't subject to much change after leaving the shop I'd definately consider the embedded route.