Labview Data Acquisition

[unclefeezus]

Hello All,

I'm an undergrad studying physics. I'm trying to write a LabVIEW VI that will set and monitor the flow rate of a single channel of a MKS 247C. The device can connect directly to my computer via a DB9 serial cable. Do I need a DAQ board to do this?

As far as my background goes, I've done a few introductory LabVIEW tutorials, but I've never attempted to connect anything to it. Also, I have some experience with computer programming. Can anyone give me advice on how to go about connecting to the device, or point me to some helpful tutorials?

Regards,
Danny Neumann

[smercurio_fc]

Not sure what an MKS 247C is, but since it connects to the serial port, then no, you do not need a DAQ board. Based on this, it seems you use the serial port to get data from the device by using the communication protocol for the device. What you actually need is an instrument driver that allows you to send commands to the device and get data from it. Over at the NI Instrument Driver network there don't seem to be drivers for that particular model, but there are for the 647. Have no idea what the differences are. You can also try to see if the manufacturer has any drivers so you don't have to try to write them yourself, although doing so is not too difficult. Check with the manufacturer first. If they don't have any, post a response and then further help can be provided.

[mikeporter]

I'm finding conflicting information: I was able to find was this reference from 4 years ago and according to the person who answered the question you will need a DAQ board. However, this document seems to infer that all you need is RS232.

Mike...

[smercurio_fc]

Hmm... that's quite peculiar. I wonder if the DB9 connector isn't actually a serial port connector, but just a signal connector. In that case, the device has no serial interface, and you can't connect it to the computer's DB9 connector. Doing so will probably damage the computer! Do you have the manual for this device? What does it say? I did a check on the MKS web site, but a search for MKS 247C turned up only 2 hits, neither of which was for the 247C, but for two devices that could be used with the 247C.

[gwd]

The MKS 247C is a controller that can talk to a computer by an RS232 bus. It controls mass flow controllers that (rarely) can have a 9-pin D type connector but much more often have 15-pin connectors or edge connectors.

No, you don't need a DAQ board. You do need Labview drivers, or a manual and a certain amount of determination.

[unclefeezus]

Thanks for your help, everyone. There doesn't appear to be a driver for the MKS 247C. It looks like I'm going to have to program it myself. The manual for the 247D is here: http://nsei.missouri.edu/manuals/hps-mks/247D_A_4channel%20readout.pdf . Hopefully, it's close enough to the 247C. The pinout for the connection that I'm going to use is on Page 43. Where should I go from here?

Danny

[Dennis_Knutson]

According to that manual, you do not have an RS-232 connection for controlling it. The way I read it, you have the option of providing 0-5 V signals or using P6 and TTL logic signals.

[gwd]

My mistake. This is a purely analog instrument. No RS232.

Goes to show that it really DOES help to read the manual.

(There are MKS instruments with a rather similar part number that are RS232 interfaceable).

[unclefeezus]

I see. How can I go about connecting to it?

Message Edited by unclefeezus on 07-19-2007 01:48 PM

[unclefeezus]

It looks like I'm going to have to get a DAQ. Any recommendations? Versatility would be nice, as I'm not sure what other applications I might need to use this for.

Danny