MKS PR4000 CONTROLLER driver for labview 8.6

[MurNesPc]

I would like to set according to the pressure inside the gas passage amount automatically.Can I do it with pr4000?

[Blokk]

What would you like to set according to pressure? Sorry, it is not clear what you would like to get. Anyway, this controller can be used to control mass flow rate, measure flow rate and measure pressure. All depends what device you connect to this controller. Anything else, any additional feature you have to program yourself. For example, you want to maintain a constant pressure in a vessel, you need to measure its pressure, and control the incoming gas flow with an MFC. But you need to write a program to do this, the PR4000 will not do this automatically...

[whaledave]

Hello all,

This thread has been vey informative and helpful for me.

I have downloaded the MKS PR4000F driver. However I'm still a bit confused.

My goal is to simply read the displayed pressure value continuously on my PR4000F with the vi on my computer. I have connected both through an RS232 serial cable, communicating on COM1. The communication is working well. But when I run say, the TEST.vi from the driver, or even the "Pilotage PR4000.vi" from early on in this thread, nothing happens. The pressure value doesn't show up. I have also double checked every other input (parity, baud rate...).

I have spent many hours trying to work this out and feel like it's not something that hard to accomplish now. Any help would be so much appreciated! 😄

Thank you very much.

Sincerely,

whaledave

[Blokk]

So you used this driver?:

http://sine.ni.com/apps/utf8/niid_web_display.model_page?p_model_id=3975

I assume you see the measured pressure value on the PR4000 controllers's display? Did you use a proper RS232 cable (as i remember, you need a "cross serial" cable, the RX and TX pins are cross connected, so a simple serial cable will not work)?

Try this VI (report error msg if you get any):

[whaledave]

Thank you for your very quick response.

Yes, I am using this driver, and able to see the actual measured pressure value on the PR4000 screen as well.

I wrote the VI you screenshot but the value still does not show up in "response". There are also no errors in the Error Handler, nor in the Initialize.vi

I should note that while I do all this and the cable is connected, the "Remote" light on the PR4000 is off. Maybe it is a problem with it being the wong cable as you point out..? I did not know there were several types of RS232.

Thank you,

-whaledave

[SVP1]

Try enabling the  remote light by pressing manually with your finger the corresponding button on the pr4000 panel.

[Blokk]

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@SVP1 wrote:

Try enabling the  remote light by pressing manually with your finger the corresponding button on the pr4000 panel.

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On my device there is no button, and there is no need to bring the device manually into "remote mode". This is done automatically when I run the "Initialize" VI...

whaledave:

It is strange you do not get any error. So I guess you have the correct cable. Could you check, what happens, if you disconnect the cable physically, and you try to run the VI. Do you get timeout error?

Another thing can be a problem, as I remember, you have two channels on this Controller (you can connect two MFC or pressure sensors). Where did you connect your pressure sensor's cable at the back of the PR4000 (cable between the sensor and the PR4000)? Or is it a single channel model?

If you connected the sensor to the second channel in the back panel of the PR4000, run the test VI with value 2 for channel input:

[Blokk]

The required serial cable (RS232) pinout is described in the manual, page 18: ( idealvac.com/files/manuals/PR4000_InstructionManual.pdf ).

Pin2 is RXD, Pin3 is TXD.

So if you have a straight serial cable, you should swap cables at pin2 and pin3. So the cable will connect the pin2 to pin3 and vica versa. You could use a multimeter to check your cable whether pin2 connected to pin2 at the two ends of the cable. If so, you need to do some cabling, or buy a "cross" cable.

Here is more info:

http://digital.ni.com/public.nsf/allkb/1EE0DD8AF67922FA86256F720071DECF

So what you need is a "Simple Null Modem Cable".

[SVP1]

Hi all, 

I am facing a problem when I try to read the flow from both channels at the same time (or check the set points of both channels). How should I work with the code? Should I have as many initialize components as many channels I want to read? In my case I want to get back 4 readings. The actual flow of both channels and the set points of both channels. 

[Blokk]

@SVP1 wrote:

Should I have as many initialize components as many channels I want to read? In my case I want to get back 4 readings. The actual flow of both channels and the set points of both channels. 

Obviously you only need a SINGLE initialization. You init your PR4000 unit specifying the serial port number (COM). After, you can read out flow rate values or check/set setpoint values for each channels. Have a look my code, there I show how to specify the channel. About what you try to do: you need to send serial commands to the unit and request string values back. It is not possible to request values "at the same time". You need to proceed in sequence. Init your unit before a while loop, and then inside the while loop you read the four values using 4 VIs from my driver set. You should also set up some timing so you get the values equidistant in time (use for example the "Wait until ms multiple" with 1000 msec to "round up" to 1 sec your loop iteration). Anyway, show your VI by attaching it (use a png snippet, i am on holiday, no LabVIEW here) so we can have a look...