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  1. #1
    Join Date
    Feb 2016
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    JCI FECs is Getting random overrides

    I知 working on a building where there was originally an NAE and 10 ac/hp units tied with FEC controllers. They recently extended the building, added an LG VRF MULTIsite manager to control the new ac they installed and took the NAE away and added a JACE. The MULTIsite manager is in the same trunk as the FEC. The issue is, every once in a while, something is overriding my compressors to start on most of the equipment. This will happen randomly, sometimes multiple times a day and sometime it won稚 at all!!! The logic in CCT is not asking for any compressor command. I would have to go to CCT and release the override and at times it would return in 5 mins. By unplugging the FEC controller from the FC trunk, the unit works perfect. When I plug it back in, it値l override the compressor command. Have some equipment where it would only override the seconds stage cooling Y2. Any help would be appreciated.

  2. #2
    Join Date
    Mar 2018
    Posts
    181
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    What about unplugging the LG controllers comm, or the Jaces comm ? See if when either is unplugged, does the override stop coming back in.


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  3. #3
    Join Date
    Feb 2009
    Location
    D/FW
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    Someone probably used the "set" command in the jace on an output and everytime the system writes it commands your outputs. Go to the point in question and look at the property sheet and there should not be any values for any priority except "out".

  4. #4
    Join Date
    Dec 2007
    Location
    Connecticut
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    Quote Originally Posted by eddiejb11 View Post
    I知 working on a building where there was originally an NAE and 10 ac/hp units tied with FEC controllers. They recently extended the building, added an LG VRF MULTIsite manager to control the new ac they installed and took the NAE away and added a JACE. The MULTIsite manager is in the same trunk as the FEC. The issue is, every once in a while, something is overriding my compressors to start on most of the equipment. This will happen randomly, sometimes multiple times a day and sometime it won稚 at all!!! The logic in CCT is not asking for any compressor command. I would have to go to CCT and release the override and at times it would return in 5 mins. By unplugging the FEC controller from the FC trunk, the unit works perfect. When I plug it back in, it値l override the compressor command. Have some equipment where it would only override the seconds stage cooling Y2. Any help would be appreciated.
    Check your tuning policy on the BO's for the compressor start command. Make sure the Min/Max write times are set to 0. If not, they will randomly start. Don't know if this is exactly your issue but it is a known issue with FEC's and Jaces

  5. #5
    Join Date
    Jul 2009
    Location
    Wa
    Posts
    442
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    Reaper has a good point. The tuning policy needs to be checked. Not sure if your using a FX jace? If it's N4 or AX? If using a FX jace JCI has created all the tuning policies for you in correlation with the correct point type. The default tuning policy before they added that feature had both min/max write times set to zero. Worth checking for sure. Another suggestion would be to delete the compressor command point from the jace, and proxy it back in as non writable. If the problem stops this confirms the jace is doing it. Also make sure somebody hasn't wrote some funky frontend logic commanding the point. If that has been done in the out slot in the property sheet it will say something like out On @14 it should be out On @ def if nothing has been linked in the priority array.

  6. #6
    Join Date
    Feb 2016
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    3
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    Thread Starter
    I haven't had the opportunity to return to the site till yesterday. The front end is Distech/Niagara. I haven't had any overrides lately but I notice my set points for all controllers have changed. I looked at the tuning policy folder at took a screen shot of them along with other things. Is there anything I missed??
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    Last edited by eddiejb11; 03-19-2019 at 11:23 AM. Reason: wrong pic

  7. #7
    Join Date
    Feb 2009
    Location
    D/FW
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    You need to null the fallback command, then you need to remove the set or set fallback slot from the action menu so that nobody can set it again. Outputs should only have override action commands.

  8. #8
    Join Date
    Jul 2009
    Location
    Wa
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    442
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    Quote Originally Posted by eddiejb11 View Post
    I haven't had the opportunity to return to the site till yesterday. The front end is Distech/Niagara. I haven't had any overrides lately but I notice my set points for all controllers have changed. I looked at the tuning policy folder at took a screen shot of them along with other things. Is there anything I missed??
    Like Chuz said release the fallback value to null. Point is operator overridden @8 right now. If you release that you would see in the out value. Start @ Fallback that is whats commanding your point. Not the logic in the field controller.

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