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Thread: First Bacnet

  1. #40
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    Ya, i limit my control networks to fewer issues.
    Plus free topology, noise immunity, and way longer segment lengths
    You wanna have a wager?
    Ft10 vs ms/tp?

    You must love Backnet time and material jobs
    Lb out
    A hundred million nodes - it's a LON story.

  2. #41
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    Oh and let's not forget ft10 speed and through-put also vastly superior to ms/tp
    A hundred million nodes - it's a LON story.

  3. #42
    Join Date
    Aug 2009
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    2,459
    It is interesting to me that the one thing that allowed BACnet to become the most widely adopted BAS protocol is the one thing that it is attacked for.

    Rs485 is never going to compare with cat6 gigabit speeds. But then again, rs485 has has been used and accepted by manufacturers for 30 or so years now. Embracing rs485 as one possible method (the slowest by the way) of BACnet communications is arguably what allowed BACnet to become the dominant protocol in just over a decade.

    Of course there are 3 other methods of BACnet comms, all of which are faster than rs485. And yes, rs485 does require color-coded wires because it is polarity sensitive. But let's be honest here. BACnet works on gigabit connections and it also works on 19.2kbps connections. But they all talk together automatically. And that's why BACnet won the protocol wars. Not because it adopted the fastest comms (which it did with BACnet/IP) but because it also adapted the lowly rs485 comms as part of the portfolio.


  4. #43
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    Dec 2006
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    What are we wagering and what is the bet?
    That you can implement a LON system better then me -> you win.
    That I can implement a BACnet system better then you -> I win.
    Which system is "better" -> unquantifiable, no one wins.
    How many LON controllers on your largest HVAC network. I have worked on a couple of projects with over 3K BACnet controllers and 90% of them resided on an MSTP bus with no issues.
    Been working with Reliable Controls lately, reverse polarity on a the comm buss and only that controller does not show up, none of this OMG the whole network will crash if you reverse the polarity. Duplicate MAC address, one controller will take it's sweet *ss time coming online (which is a great indication you have duplicate MAC address), none of this OMG the whole network will crash if you have duplicate MAC address. Duplicate device instance same as duplicate MAC address. All running at 78.8kbs. Only difference is I have to address the controllers before they are brought online. Their latest rev of BACnet controllers don't even require this, took a leaf from the LON world and they default to their serial number until you set a MAC address and device instance, so install, record S#, location and power up, auto-baud as well. The gap is closing.

    kontrol out
    "Open is as open does." - Forrest Gump
    "Can't we all just get a Lon?" - Garry Jack
    "BACnet: integration or interrogation?" - The Janitor
    "Open protocols? You can't handle open protocols!" - Nathan R. Jessup
    “What’s that? Aaa… open protocols? Don’t talk about…. open protocols? Are you kidding me? Open protocols? I just hope we can hardwire an interface!” - Jim Mora http://www.youtube.com/watch?v=U7fjDS0jKiE

  5. #44
    Join Date
    Mar 2007
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    274
    Quote Originally Posted by lonboy View Post
    No way would I ever consider an archaic technology such as MS/TP
    you must be lucky to have that option.
    I don't have the luxury of deciding which protocol will be used
    i would be out of business if I only consider jobs that have my preferred protocol !!

  6. #45
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    Apr 2007
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    Amarillo by mornin'
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    Quote Originally Posted by kontrolphreak View Post
    Their latest rev of BACnet controllers don't even require this, took a leaf from the LON world and they default to their serial number until you set a MAC address and device instance, so install, record S#, location and power up, auto-baud as well. The gap is closing.

    kontrol out
    Damn, that is slick. This is KMC your still talking about?
    "It's not that I'm smart, it's that I stay with the problem longer”
    Albert Einstein

  7. #46
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    No, Reliable Controls.
    Their new MACH-ProZone and Smart Space Controller.
    Andover has something similar and KMC has auto MAC addressing.

    kontrol out
    "Open is as open does." - Forrest Gump
    "Can't we all just get a Lon?" - Garry Jack
    "BACnet: integration or interrogation?" - The Janitor
    "Open protocols? You can't handle open protocols!" - Nathan R. Jessup
    “What’s that? Aaa… open protocols? Don’t talk about…. open protocols? Are you kidding me? Open protocols? I just hope we can hardwire an interface!” - Jim Mora http://www.youtube.com/watch?v=U7fjDS0jKiE

  8. #47
    Join Date
    Dec 2011
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    Winnipeg,Manitoba
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    So I have that whole system running that started this original thread, the only thing complaint is that the BACnet MSTP speed seems somewhat slow. for example it could take 1-3 minutes to shut a fan down on one of the 6 Johnson freq drives.

  9. #48
    Join Date
    Dec 2011
    Location
    Winnipeg,Manitoba
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    33
    Forgot to mention that I don't have any EOL's mounted at any end because it made things slow and then unstable, and because I'm using a Johnson FX60 as the only master Johnson recommended we use there 24volt powered EOL's which made things worse so somehow it worked out the best open. The furthest wire run on the Belden is 350 feet.

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