Troubles in reading data points from the equipment

Hi!

I have also a chiller from Carrier and I'm having troubles in reading data points from the equipment.

I have PXC200ED on the same LAN as the chiller and both are using BAC0. The chiller has the instance object number 1600001 and it is unique on the bacnet lan.

I have used Yabe to get the EDE file from the chiller, but when I choose any of it's points in IO editor, from CFC, it gives me the error: "target device is unknown " on the analog input object in CFC. On the equipment the point is an Aval.

Has anyone had this problem? The bacnet stack is enabled in the unit and in Yabe I can see all the chiller and PXC station on the same LAN.

I have also turn power OFF and ON on the chiller and also tried the direct addressing has indicated in this post but it result is the same: "target device unknown ".

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Split from BACnet 3rd party integration to Desigo PXC.

 Thank you so much _CJ. It worked for me this form of addressing. I had to use polling for it.

When I used the [1600001] following the text of the point it did not worked, only using [1600001][2,103] that is the number, in AVAL, of working hours of the machine it worked.

I do not understand why it does not accept the text format of addressing of the datapoints. Some equipments accept it and other don´t?

_CJ

Hi,

It may the case that the Chiller controller does not support COV, i.e. it will not transmit a COV onto the network. Have you tried setting the Polling Time on the PX analog input? It defaults to 0 seconds, try setting it to 10 seconds for example.

For the addressing on the PX analog input, is it in the format 'B=[1600001][x,y]'? (where x is the object type, and y is the object instance number for the analog point you want to read from).

Regards,

 Once again, very good explanation. Thank you _CJ!

_CJ

Hi,

Thanks for confirming that the issue is now resolved.

Not all devices support the integration being done using Object Names. This would normally be specified in the BACnet documentation for the 3rd party controller.

As an example, if you look at the attached PDF - pages 6, 9, 15 & 16 - reference is made to Object Names being supported. For this type of device, PX addresses can be either mapped with the Object Name, or by using the method detailed in the posts above.

Also attached is a screen dump from the EDE dump for the device detailed in the PDF. The format for using the Object Name mapping would be B=[10]Unit001_RA. The format for using the 'hard' address mapping would be B=[10][0,100108]. (Note the absence of square-brackets when using the Object Name).

For devices that don't support COV, the Polling Time needs to be set for Inputs to force the PX to Read the value, otherwise the PX will never be able to receive the value from the 3rd party controller.

For Outputs to the 3rd party controller (in your case, maybe the Chiller flow temperature setpoint) if the value of the PX output is changed, the value is written to the 3rd party controller by the PX using COV, which is fine. However, if the 3rd party controller is power-cycled, the value will revert to it's Default Value, and will only ever be updated again if the output in the PX is adjusted. This is where the output Heartbeat Time comes into use. The Heartbeat defaults to 0 seconds, so setting this to 10 seconds for example will cause the PX to Write the value to the 3rd party controller every 10 seconds. So, within 10 seconds of comms being re-established, the value in the 3rd party controller would be updated.

Regards,