LabVIEW
Bronkhorst Labview-Flowbus System Integration
I'm not sure I understand. Controlling the Bronkhorst Flow Controllers through the LabVIEW library provided by Bronkhorst should be quite possible. One of the controllers will have to be connected to the computer through the serial port and all controllers are connected through the Flowbus with each other with the according Bronkhorst cables, adapters and terminator plugs.
What is your problem exactly? Accessing the Bronkhorsts? Controlling the solenoids? How have you connected the solenoids to your computer?
If you want to control the solenoids from your Massflow controllers you certainly have a problem. Depending on the type and configuration of your device, you can order it with a custom function on pin 5 of the main DSUB-9 connector. This can be an analog or digital input or output. As digital output you have either the option to have it be active on alarm or a below a certain flow. But the controller has to be configured at factory for this and you have only at most 1 output per controller. I also don't think you have any possibility to control that output yourself arbitrarily but simply have it work as alarm or below certain level output.
There is a LibVIEW library from Bronkhorst that lets you communicate with Bronkhort flow meters and controllers
https://www.bronkhorst.com/int/products/accessories-and-software/flowware/labview/
It works for basic requirements quite well!
You connect one Bronkhorst device through serial to your computer and the others are connected over Flowbus to this first device. This requires the Bronkhorst devices to have Flowbus interface (a RJ-45 type connector on the top) and the according Flowbus connecting cables and terminators.
When you commission the system you have to assign each controller a unique Flowbus nodeID and then you use that nodeID to communicate with the device(s) from LabVIEW.
According to the manual, there is a parameter (NODE ADDRESS) that you can use to address each individual valve in the network.
LVNinja already pointed out to you the LabVIEW side. Each Flowbus device needs to have its own unique node address. This is assigned to a device in a number of ways:
1) there is an initialization sequence where you push the little button on the device during power up for a certain amount of time. The exact procedure varies per device type but you basically hold the button pressed as the two LEDs on the device go through a sequence of blinking patterns and release the button at a certain pattern. (The devices I used in the past had 4 seconds per pattern and I had to release the button during the third). This initiates a sequence in the device where the device will search for other already assigned node addresses on the Flowbus and then select the next available one, starting at node address 3 if it can't find any other device. In this way you add device per device to the Flowbus and go through this startup sequence for each as you add it and power it up.
2) In my case I had trouble to get more than 7 devices initialized that way as the 8th device for some reason refused to find that it should use node address 10. After some support call to Bronkhorst, who did respond within very reasonable time of one day and a little back and forth, they recommended to me to use their FlowSuite software. In there you can let it find a connected Bronkhorst device and it will query it for all connected Flowbus devices. And you can per device change the node address. With a little back and forth and disconnecting and connecting the various devices in the right order, I managed to program each device to its own node address.
3) After all devices show up properly in the FlowSuite software, you can use the LabVIEW VIs from Bronkhorst (you need to close FlowSuite in order to be able to access the serial port from within LabVIEW) to communicate with each device by specifying the actual node address in the node parameter for the particular VI. In that way I could control and read all 9 flow controllers in realtime very easily.
This was a fairly simple application that just controlled the 9 flow controllers based on a recipe and then read back the current flow once every half second or so and logged it to disk. For more complex applications it would be useful to go with an actual framework like DQMH or similar instead of the very simple queue with notifier design used here. Not because it is bad, but once you start using more independent "engines" like the above in an application, the overhead of creating a new separate queue and according message infrastructure for each over and over again starts to get burdensome.
1) My problem was that the automatic node address initialization from pressing the little button on the device during power up was not willing to auto assign a node address above 9. By the first device having always a node address of at least 3, this did not let me get more than 7 devices properly configured, but I needed 9 devices (node address 3 to 11).
2) It is simply a number (between 3 and 80) assigned to each Flowbus device that needs to be unique on the whole Flowbus and that the device will maintain in its resident memory even while the device is powered off. When started up again it will remember that node number and use that. Any message on the Flowbus contains as one of the first elements this node address and a device only will consider a message for itself if the node address in a message matches its own node address (or is addressed to node address 0 which is a broadcast to all devices on the bus).
3) All the Bronkhorst VIs have an input parameter "node". This is the "node address" of your specific flow meter or controller to communicate to it. If you want to talk to a flow controller with a node address of 3 assigned, you would wire a 3 to this terminal, and accordingly a different value for other devices.
