Publishing data from a flow meter, via foundation fieldbus, to a host device (PC) for data acquisition.

[akedz]

I have an application where I need to receive data from a flowmeter, via foundation fieldbus, to a host device (PC). The data will be used by a LabView application for monitoring.

How do I setup the flowmeter to publish data out to the host device? Do I develop a function block application (in NI-FBUS Configurator) with the AI block connected to a Trend block and download this to the Link Active Scheduler?

The host device has an AT-FBUS card connected to the flowmeter. Communication has been established with the flowmeter. The flowmeter is being used purely for data acquisition in the system.

[Fbus]

First of all, you can NOT setup dedicated publish data from FF device to the host device deterministically; if you want to use LabVIEW, you don't need to configure a trend or schedule for host, what you can do is to update (read in a certain period) data through OPC (DataSocket) in LabVIEW, but it is not deterministic.

Secondly, when you configure the data you want to monitor in LabVIEW, you can adjust the OPC update rate to fit your requirement.

If you don't like OPC solution, please wait for the upcoming NI-FBUS Communications Manager 3.0 version, which will come up with a specific LabVIEW VI library for Fieldbus. It is said the 3.0 version would be released this year, you can contact "fieldbus.support@ni.com" for further information.

[akedz]

Thank you for your quick response. I have just starting working with FF.

I will be using LabView DataSocket to acquire data from the FF device. (I have already been able to view data using Server Explorer.) What then is required for the FF device and the host adapter. Do I simply configure the AI block for the FF device? And then do I need to develop any function block application? The FF device is being used only for daq and is not linked to any process control.

Thank you again for your assistance.

[Fbus]

Nice to hear it helps.

If you just want to use FF device for data acquisition purpose, you don't need to develop function block application. But please be aware that the data you get from FF device through OPC (or NI-FBUS software) might not be deterministic or real-time.

However, if there is no other FF device or other fieldbus communication activity, and the data you need are not too huge, it should be acceptable to acquire data through DataSocket (OPC).

Anyway, it is still not a good solution for higher speed daq application. Just my opinions.

[akedz]

High speed daq is not a requirement - process is fairly slow and sample rate will be on the order of a second. I'll be recording four points of data from the flowmeter (mass flow, temp, density, total flow). Flowmeter is the only FF device on the bus. It's not the optimum solution - just a compromise.

I was able to view data using OPC sample VIs in LabView. All I did was configure the AI block and then place the block in the function block application. I'll try it without the function block application today.

Thanks again for your assistance.

[Regis Lee]

akedz,

if you don't mind me asking, what type of flow meter are you using?

Regis


"akedz" wrote in message
news:5065000000050000004CC70000-1042324653000@exchange.ni.com...
> High speed daq is not a requirement - process is fairly slow and
> sample rate will be on the order of a second. I'll be recording four
> points of data from the flowmeter (mass flow, temp, density, total
> flow). Flowmeter is the only FF device on the bus. It's not the
> optimum solution - just a compromise.
>
> I was able to view data using OPC sample VIs in LabView. All I did
> was configure the AI block and then place the block in the function
> block application. I'll try it without the function block application
> today.
>
> Thank
s again for your assistance.