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  1. #1
    Join Date
    Mar 2006
    Location
    Coats, North Carolina
    Posts
    53

    BACnet Schedule to ALC

    Has anyone been able to publish BACnet schedules to AutomatedLogic? It's working great with Johson Controls Metasys, but we have hit a snag with ALC. ALC can see the schedule and the object name, but the start/stop dates and times are not coming over. Any help would be greatly appreciated. Thanks!!!!

  2. #2
    Join Date
    Aug 2009
    Posts
    2,459
    I'm curious as to exactly what you mean by this.

    What are you using to make these schedules that you are trying to push out to the ALC controllers? Is it something like a Jace?

    Secondly, what variables are not showing up when you query the ALC controller? You mention "start/stop dates" which makes me think that you are describing the "Effective Period" variable but then you mention "times" as well and that's confusing me.

    It is possible that these controllers are not fast enough to operate a fully functional schedule. As an example, to be compliant a controller only needs to support a weekly schedule or an exception schedule. Of course all of the controllers I've played around with support both but this could be an example where the schedule was set up to only support one type of scheduling and you're polling for the other type.

    Post some more details and I'm sure we'll figure this out for you.

  3. #3
    Join Date
    Mar 2006
    Location
    Coats, North Carolina
    Posts
    53
    Thanks for looking at it. We are publishing BACnet schedules with an AX JACE to JCI Metasys systems and the JCI system can read the schedules that we are pushing out. For instance, the schedule contains the Schedule name, Target name, object name, object type, instance number and value.

    With the AutomatedLogic system, we can see and read the BACnet Object type and object name, but the start date andf end dates are showing asterisks where the where the month/date a year should be showing up.

    The AutomatedLogic PICS shows the following:

    BACnet Protocol Implementation Conformance Statement
    Automated Logic Corporation LGR25, LGR250, LGR1000

    Schedule (ENUM):
    1. Creatable? NO
    2. Deletable? NO
    3. Optional properties supported:
    description
    exception-schedule
    weekly-schedule
    4. Writeable properties:
    description
    effective-period
    exception-schedule
    priority-for-writing
    weekly-schedule
    list-of-prop-reference
    5. Proprietary properties: None
    6. Range restrictions:
    description limited to 50 octets in length
    exception-schedule
    limited to 30 BACnetSpecialEvents,
    each being limited to 6 BACnetTimeValues
    present-value 0 to 4294967295
    relinquish-default 0 to 4294967295
    weekly-schedule limited to 6 BACnetTimeValues per

    I have to believe that there is something that is not set correctly on the ALC system since we are using the sames process on othe systems such as Johnson Controls. In any case, thanks for asking. If there is anything that you could add, I vertainly would appreciate it.

  4. #4
    Join Date
    Aug 2009
    Posts
    2,459
    The LGR product line was BTL listed in 2005 and claimed conformance to the 2001 BACnet specification. Back in 2001 the schedules were much as they are today but there are a few differences that are noteworthy.

    Specifically, there was no "schedule default" variable, nor were there "status flags" "reliability" or "out of service." Reading through your stated issues, the most important of these is the schedule default.

    Because of the lack of a default, the method of setting up one of these old schedules is a bit different than a modern BACnet schedule. It is possible that your JACE is trying to automatically make use of this scheduling feature and that's being rejected by the old-style ALC controller.

    You will need to sniff the network transaction to be sure what the problem is. The actual rejection message sent by the ALC controller will help immeasurably in determining what needs to be modified.

    Can you post a wireshark capture of this interaction?

    Edit- Please note that schedules in new BACnet controllers need to be able to be set up to be used exactly like legacy 2001 BACnet controllers. They simply also have to have the more advanced features that have come into the system over the years.

    The front end *should* be smart enough to take this into account automatically if the schedule can only be set up in the 2001 way.

  5. #5
    Join Date
    Mar 2006
    Location
    Coats, North Carolina
    Posts
    53
    Thanks once again for the info. In the end, I'm just trying to push the schedule down to the local controller so that it can decide when and what it needs to do. I can publish an analog point value and have the ALC unit react to what the analog point value is, but I would rather see the ALC hold that actuall schedule. In the meantime, I'll see what I can capture on the interaction.

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