Unison USAP long distance

I have a unison legacy system that wants to add integration to an A/V system.  The A/V system is to be located about 100-150' away, as the cable flies.

There is also currently  11 walls and 4-5 zones per section.  What this means, is that an A/V station will need to change pages in order to have feedback for all zones, and control of all walls and presets.  Therefore,  I'm assuming that USAP is the way to go.

So, does anyone have experience with serial extenders, repeaters, etc (something B&B may have?)  For $100 or so, I can convert to current loop or 485 and back again.  I think that will be cheaper than an A/V interface..and much easier to program. (no dummy zones and templates, etc)  Has anyone tried this? 

Kind of related, but how does RS232 over a cat5 or cat6 wire compare to the traditional spec cable and its15m limit?  Has anyone looked at this in any detail?

Thanks

 

 

  • I use to do this all the time. AMX makes devices to do this, but so do several rather cheap online retailers. I even built one from parts once. Price here isn't so much the issue, as you will probably not make up the cost difference between running 8471 for an AV station compared to 9729 or equiv for Serial. (Use a real shielded serial cable like 9729).

    Have a look at bb-elec.com. they have several cheap and easy solutions for 485, 422, Ethernet, and even some more odd ball ideas. Remember termination if you go 485..

    Keep in mind there are design differences to when AV stations are good and USAP is better. When an AV station is placed in a config it is part of the ROOM just like a station, or in a section just like a station. The same property restrictions apply. Whereas USAP can control everything and is not a member of any room. There are advantages and disadvantages to each, but important to consider when adding this functionality.  Also, an AV station allows the light manager programmer to control the access to the Unison system, whereby USAP allows free access to the remote system. There are several other pros and cons, but that’s the gist.

    Best of luck.

     

     

     



    [edited by: mskurla at 8:51 PM (GMT -6) on Thu, Jan 14 2010]
  • Converting to RS485 and back is probably going to be your best bet.  Any such converter will work just fine as they're mostly too simple to screw up.

    Cat5 wire would be an option, though by itself it probably doesn't give enough extra length.  I would also still recommend either shielded cable or installing it in a grounded metal conduit.  RS232 is an unbalanced signal, which can make it more susceptible to electrical interference.  Converting to RS485 helps with that a bit, but I still prefer shielded wire. 

    This website has some good information on RS232, including a section on cable length. 

    Keep in mind too that there are a lot of ways you could do this that would be almost correct.  For example, that website says that Cat5 wire should be okay up to 147'.  You could round that up to 150' for your application and it would probably work while you're testing it, but it may not be reliable long-term.  You definitely want to aim on the side of being overly cautious.

  • As others have suggested the 485 route is pretty clean.  The B+B boxes work great!  We do AMX intergration and generally us a IP to RS-232 box at the far end.  It looks like a "real" serial port to AMX but on the network.  The B+B work great as a wire streacher.

     

    KEN

  • So I'm thinking the IP->RS232 could be the easiest way to go. 

    I actually have very little experience with the actual programming of a Crestron  (or what ever system actually will get installed in this system).  I have always just told the A/V guy what I need to see...and what they get back from the lighting system...and they have just done it....and it worked and all was good in the world.

    So all you Crestron programmers out there:

    How common would it be to have a system that can access an IP COM port?  I would think there would be special drivers needed.  I guess I could always use a RS232->IP->RS232 tunnel....but if I'm using two interfaces (one in one out) then I think an RS232->RS485->RS232 would be lower cost.

    Any thoughts on this?

    I am leaning away from an A/V interface because the system has too many Zones and Walls that need to stay in sync with the A/V system.  How easy is it for a Crestron system to deal with pages on an A/V station (so that the LED zones and Walls are spread over multiple pages, and the first few LEDs signify the current page)

    Thanks

  • I've done some Crestron programming with the Crestron processor talking serial directly to the CME. It worked pretty well, but one thing you might want to verify is which revision of firmware is running in the CME, as ETC made some major improvements along the way. My recollection is that a major change to the protocol happened around the middle of 2005 - originally the serial protocol was strictly polling based, but the most recent protocol has some push functionality which made the Crestron interface much more responsive.

    For your question about IP com ports, the easiest way (and since it's Crestron's solution - fairly pricey compared with a generic IP serial port) is to put in a QM-RMC in slave mode. It can sit on the Ethernet and gives 2 COM ports at the remote location. Cost is around $350 or so.

    AndrewY