PCG2621: Application Command VS "HW Cmd"
Results 1 to 11 of 11
  1. #1
    Join Date
    Jan 2012
    Posts
    144

    PCG2621: Application Command VS "HW Cmd"

    I'm having a bit of trouble trying to get the PCG2621 application to run independently, such that specific commands are not "overwritten" by the Front End FX60.

    What I am noticing is that when the program is not connected to the FX60, I can simulate and verify the proper sequence that I want.

    However, I am in the preliminary stages of integrating it onto the FX60, by discovering the controller, adding it to the network, and scanning the points to add.

    What I notice here, is that when one of my equipment should be ON, the FX60 points list shows that it is OFF. This point is override-able, and so it is displayed with "Off @16". This is the current state; OFF, when it should be ON.

    I am only on my first controller, and purposely added a single point to test this specific issue, trying to find a way around it. I hope that someone else has encountered the same issue.

    When I connect to the PCG2621 controller, either via Bluetooth, or through a bacnet commissioning device, I can see that my program is "trying" to turn ON the pump, but the "HW" part is overwritten as OFF.

    Is this the side effect of having the FX60 on the network? All I did was add the command point (that's able to be overwritten), but I did not test the override ability yet.

    What I want is to allow the operator the ability to override the command point, but otherwise, the command point itself will switch to on or off, depending on what my application wants.

    Would "Restore Command Procedure" be the reason? I can't see this being the case, because it is only valid if the controller loses all power, and starts up without the FX60 being online.

  2. #2
    Join Date
    Jan 2012
    Posts
    144
    I also noticed that when I am in the PCT application, when I right-click on the point, click on HW Commands, the default radio button is set to the "Inactive" slot.

    No matter which HW Commands I tried, it doesn't turn off the HW command. I think if I override it to ON, then release it, it will stay ON.

    But I can't see why this is happening.

  3. #3
    Join Date
    Feb 2009
    Location
    Northeast
    Posts
    342
    First, is there other equipment on the BACnet that could be writing to this point? Other controllers? Another Supervisor? Anything else on the network?

    This sounds like there is something in the FX60 commanding the point to OFF at priority 16. Things to check on the FX60. Look at the link sheet for the point in the FX60. Make sure there is not something linked controlling it.

    Then open the property sheet. Can you see anything in the priority array.

    If you have not found anything yet try this: On the priority array in the property sheet there should be an arrow at each priority level. Click the Arrow at priority 16 to show the null box and the value box. Clear the null box for priority 16 and click save. Check the null box for priority 16 and click save. Does the point work now? Yes, Great! No, try again at priority 15... Get the idea?

  4. #4
    Join Date
    Jan 2012
    Posts
    144
    billcontrols,

    thank you for your insight! It seems that In9 is the culprit, I am not entirely sure why this would happen. I tried def, In16, In15, and each of them, when I de-null (set to OFF), the command would come ON, but when I null the point again, it would go OFF again. I decided to jump to In9 (because In8 is the user override) and when I de-null and set to OFF, the command would stay OFF. When I put In9 to ON, the output would come ON. Upon re-nulling In9, the output stayed on the command that the controller application needs. Would you have any idea why?

  5. #5
    Join Date
    May 2011
    Location
    North Carolina
    Posts
    299
    When in commissioning mode in PCT for the binary output you see that the application says the output on "on" but the value beside HW: is "OFF". Is that point in PCT an orange color indicating that the software and hardware values do not match?

    Do you have an operator override on in PCT? Disconnect the FC bus from the PCG. If the point in PCT is still orange then right click and select hardware commands and then release operator override.

  6. #6
    Join Date
    Jan 2012
    Posts
    144
    syscontrol,

    Yes, it is an orange color, and yes, it does not match.

    What happened was that as soon as I downloaded the application onto PCT, I connected to the FX60, and discovered the points. At this point, they were still "Active".

    As soon as I added the point to my points list, in less than 1 minute, it would change to "Inactive".

    I can disconnect from FC bus, but I'm certain that if I can release the command, and put the FC bus back in, it will overwrite again.

  7. #7
    Join Date
    Feb 2009
    Location
    Northeast
    Posts
    342
    "Would you have any idea why?"

    I am not the most expert, but this is my understanding...
    Something on the network set that BACnet address to "off". Points in the FX60 are "proxy points" and do not seem to discover overrides that pre-exist the Bacnet point discovery. So the PCG had an override on the point in question at priority 9 but the discovered proxy point in the FX60 did not show it. Proxy point priority tables match up with the BACnet point priority table, but they are not the same thing. Since they do match up by De-nulling then re-nulling the point in the proxy point you sent a bacnet command then released the command to the real Bacnet point.

    The real question I have for a real expert is: Will the commands from another bacnet master show up on the proxy point of the FX60 if it occurred while the FX60 was online with the point configured. I suppose I will have to test this sometime.

  8. #8
    Join Date
    Apr 2013
    Posts
    3
    Go to your default tuning policy in your BACNet driver and make sure that that max send time is 0 and the write on start, write on up and write on enabled are all false. This will clear everything up. If you want to write to network variables create a new tuning policy that has a max write time of around 10 minutes and apply it to only those points. That will give you optimal performance.

  9. #9
    Join Date
    Apr 2013
    Posts
    3
    The commands from another bacnet device will show up in the priority array but you won't see it on the proxy point. In fact if you override a Network Variable and then delete the point the override will stay on the PCG point permanently. Even cycling power to the controller will not clear it up because the PCG is set to reinstate overides on startup. If you were to add this overridden point back on your FX60 you would not see that it is in override. You could however add a status flag on the proxy point that would tell you it was overridden.

  10. #10
    Join Date
    Jan 2012
    Posts
    144
    GWILL,

    By default, "write on start", "write on up", and "write on enabled" are TRUE. I thought that by having these true, once the FX60 boots up, it will send whatever command is required at that time (for example, from a schedule), or whatever the user had overwritten before the FX60 "lost power". I'm also not sure why this would be the reason why it would overwrite at In9?

    What is the point of "write on start", "write on up", and "write on enabled", and when should these be used?

    I have other tuning policies in order to reduce stress on the network. Such as:

    OAT that is linked to multiple controllers are written every 3(min) to 5(max) minutes.
    Schedules linked to multiple controllers are written every 5(min) to 10(max) minutes.

  11. #11
    Join Date
    Apr 2013
    Posts
    3
    [QUOTE=Questionz;15597161]GWILL,

    By default, "write on start", "write on up", and "write on enabled" are TRUE. I thought that by having these true, once the FX60 boots up, it will send whatever command is required at that time (for example, from a schedule), or whatever the user had overwritten before the FX60 "lost power". I'm also not sure why this would be the reason why it would overwrite at In9?

    What is the point of "write on start", "write on up", and "write on enabled", and when should these be used?

    I have other tuning policies in order to reduce stress on the network. Such as:

    OAT that is linked to multiple controllers are written every 3(min) to 5(max) minutes.
    Schedules linked to multiple controllers are written every 5(min) to 10(max) minutes.

    Essentially (write on enabled) will send commands to a point when that point is enabled. (Write on up) sends the commands to points when the controller it is on comes online. (write on start) writes to all proxy points when the Supervisor Starts. Max Write time is the maximum time between writes which essentially makes sure your command is being repeated regularly. The writes associated with these settings will go out to all writable proxy points when the specific event occurs. What isn't obvious is that null commands can will be sent out to the writable points in some of these cases. A BO is mapped as a writable proxy point and if it is added to the network when its output is on and (write on up) is true a null command may be sent to the point. This will cause the point to go to its relinquish default value. It may not be updated until the controller updates its command. If you set the Default tuning policy as I suggest this will not happen. I like to set my custom tuning policies up the same way. The only settings I am now using are min and max write time. If you lose power on your controller you could be unoccupied for 10 minutes however you eliminate a lot of other potential issues. Every Manufacturer of BACNet controllers do things just a little differently. This setup works with all that I have tested to date.

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