Results 1 to 11 of 11
  1. #1
    Join Date
    Sep 2009
    Posts
    25

    Trend Controls 3XTEND

    Hi There,

    Hoping some of the Trend experts might be able to help out !!

    Is there a recommended number of LON devices to hang off a 3XTEND? Like anything I imagine there is a maximum number of devices however there is also an OPTIMUM number of devices to ensure fast response etc.

    I am looking at a job that has 300 IQL-VAV devices on one 3XTEND, divided up by routers (IQL Router) could this be percieved as excessive??? In attempting to solve some issues we are considering adding some 3XTENDS so it would be nice to know what the optimum number of VAV's for good response time would be.

    Any comments welcome.
    Cheers

  2. #2
    Join Date
    Jan 2003
    Location
    USA
    Posts
    1,657
    I personally would not put that many on devices on a single extend. Mainly because if it fails I just lost the whole dang building. Also if your not careful with the amount of traffic passing through it, it will likely lock up. This would happen really often on the old firmware, which I would make sure its current on this one for sure. If I designed this system I would have broken the lon network over at least two extends.

    In the past I have had little issue with ~150 devices to the extend pending my comms over the network are in check.
    Propagating the formula. http://www.noagendashow.com/

  3. #3
    Join Date
    Sep 2009
    Posts
    25
    Hi Orion,

    Thanks for the advice there are around 2,500 IQL's in the building so when they lose one they lose about 6-8 floors. However even this is a bit dodgy.

    Is it possible to alter the points exposed to the LON network in the IQL-VAV?
    Our advice so far is that the device is not programmable....or shall we cannot be altered.

    The second issue was that the best update times (say to poulate a screen of VAV data) is about 40-50 seconds for around 30 values all from the same device would you expect this sort of population speed normally?

    The 3XTENDS are being polled by IQ3 controllers used for logging and they are logging around 5-7 values (VAV type dependant) every 15 minutes which would cause a fair amount of traffic.

    The worst part about the way the system is configured is that all data from the buildings comes through a "master" 3 XTEND for each building, if this falls over ALL access to the building is lost.

    Anyways I think spreading the love by adding 3XTENDS may be a worthwhile excercise.

    Thanks for your assistance

    PBW

  4. #4
    Join Date
    Jan 2003
    Location
    USA
    Posts
    1,657
    >Our advice so far is that the device is not programmable....or shall we cannot be altered.

    That's not totally true. They can be programmed, however you need to send in the files and have them compiled, then you can do a firmware download to install them. Programming them is less than straight forward.

    >is about 40-50 seconds for around 30 values all from the same device would you expect this sort of population speed normally?

    Nope, that seems excessive. It’s likely due to the traffic.

    >IQ3 controllers used for logging and they are logging around 5-7 values (VAV type dependant) every 15 minutes

    Yikes, hope that is staggered out and not hitting all at once on the quarter of the hour. If it's not, that is going to be nothing but problems.
    Propagating the formula. http://www.noagendashow.com/

  5. #5
    Join Date
    Sep 2009
    Posts
    25
    Thanks for the feeback Orion.

    This helps a lot. I was sure the Trend systems I had seen in the past were significantly more responsive.

    The reprogram ability sounds like a possibility our client would be happy to think about.

    Its quite a significant sized system and the local agent is doing stuff all to assist....not only are there lumps every piece of carpet but the cupboards are bursting at the seams with skeletons!!

    I appreciate the heads up!

    Cheers
    Brendan.

  6. #6
    Join Date
    Apr 2007
    Location
    Amarillo by mornin'
    Posts
    853
    Quote Originally Posted by orion242 View Post
    >Our advice so far is that the device is not programmable....or shall we cannot be altered.

    That's not totally true. They can be programmed, however you need to send in the files and have them compiled, then you can do a firmware download to install them. Programming them is less than straight forward.
    So Orion, with Trend you are not able to do your own program changes?
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  7. #7
    Join Date
    Jan 2003
    Location
    USA
    Posts
    1,657
    This only applies to the lon controllers, which in all fairness are sold as a non-programmable ASCs. All other controllers, including the new BACnet line, are fully programmable without any extra bs.
    Propagating the formula. http://www.noagendashow.com/

  8. #8
    Join Date
    Apr 2007
    Location
    Amarillo by mornin'
    Posts
    853
    Quote Originally Posted by orion242 View Post
    This only applies to the lon controllers, which in all fairness are sold as a non-programmable ASCs. All other controllers, including the new BACnet line, are fully programmable without any extra bs.
    Thanks for the reply thus far Orion. I got another question for you. What type of
    Programing language do they use? Is graphical block style or line coding? TIA
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  9. #9
    Join Date
    Nov 2007
    Location
    Clayton, NC
    Posts
    42
    All Trend controls are programmed using graphical function block programming.

  10. #10
    Join Date
    Apr 2007
    Location
    Amarillo by mornin'
    Posts
    853
    Quote Originally Posted by NC Trend View Post
    All Trend controls are programmed using graphical function block programming.
    Thanks. I read on their site that they are "somewhat" territorial. How true is this?
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  11. #11
    Join Date
    Jan 2003
    Location
    USA
    Posts
    1,657
    It's true. You can PM me if you want more details.
    Propagating the formula. http://www.noagendashow.com/

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event