Hey guys

now, first off im a TOTAL newbie at this PLC magic so, please dont laugh if my question is stupid - and it probably is!

Im currently working on a baggage system design and we have decided that we need to find some large(ish) screens that can

a; be seen from about 20 meters away
b; display either one line of 14 characters or two lines of 7 characters
c; connect to Siemens PLC's via Profibus
d; be as simple as possible to ensure that reliability is as high as possible (no Windows crashes here!)

Basicaly, these screens will be used in the dirty, dusty baggage halls to display flight numbers. I've tried looking with Google but got stumped - apart from finding this forum.


Hope someone can recommend/point me in the right direction and thanks in advance!!!!

Typically a display like that is called a marquee. I know Uticor and Exor others make such devices, though I cannot say which can communicate via Profibus.

ezautomation.com sells essentially "Uticor" brand stuff but the marquees are significantly cheaper. Primary difference is that the driver board doesn't have the "sophistication" of a real Uticor. Uticor boards allow you to trigger messages simply by triggering different inputs...you can have a marquee with relay logic only (no PLC, no serial port, etc.). ezautomation version does serial ports (or Ethernet or a few other buses) ONLY.

Support for Profibus is often weak, partly because it is difficult to work with overall and results in lots of calls to tech support. Only major vendor that loves it is Siemens. You may find yourself having to put in a converter to get from Profibus to something else such as Modbus.

Another option is the HMI's from Red Lion. One possible vendor is omega.com but they have lots of vendors. They have the "giant" display for their Gxxx series HMI's. These HMI's are some of the most rugged around I've found in the first place. The "giant" display is a "grey scale" (actually, a big array of LED's) display that attaches to one of their displays. Look on their web site for more info (www.redlion.net) or on Omega's (www.omega.com). The advantage here is that you're not limited to the marquee-type stuff.

A third option would be any HMI that works on a PC, don't get me wrong...XP can be very stable these days if you get all the current patches and don't load it up with anything other than it's intended purpose. You need a very solid industrial grade PC such as the boxes that drive the HMI's from CTC Parker, or even their software. Look for PC's with no hard drives and no fans. The "UNO" PC's from Advantech work very well, although the plant I work in (mining) uses them as thin clients. Put everything onto a flash card and use Windows XPe (embedded)...so you can "write protect" the system (reboot = restart from where you built the system). Or else find an HMI that has a VGA connector...

...And then buy a "big screen" LCD TV with a VGA connector and mount it in a big box (for cooling). Put in a large piece of lexan for the window to see it. So you get the effect of a "giant screen" LCD but keep everything nicely sealed away. This is another way that this trick is commonly done. Some folks try to put the "PC" (whatever it happens to be) in a separate room and pipe the video in. This can work too but you will find there are resolution limitations to doing this. I used it to put 4 screens directly on the floor of the casting department in a cast iron foundry (unbelievably nasty environment). We put in a 4-output VGA card from Matrox that supported composite video output and put in small 9" black-and-white composite video cameras. Only time the system ever went down is when they accidentally burned through the coax every few months. Fortunately this was easily replaced and relatively inexpensive. Resolution was horrendous but we were using something like "24 point" fonts on the screens.

wow.... awesome post mate and appears to be exactly the sort of info i'm after, thank you!!!!


(Sorry for the slow reply, just got back to work)