LabVIEW and Honeywell Read-out Box

[seb_Dai]

Hi,

I am completely new to LabVIEW and need help here.

I am trying to use LabVIEW to record the pressure reading on a Honeywell read-out box with its one end connected to the transducer and the other end connected to the computer (LabVIEW). The part number of the Honeywell read-out box is 060-1833-18. Both the transducer and the read-out box are working fine and they are showing correct reading. However, the LabVIEW software shows up error code: 1073807339 (Time out error). I know that this type of error shows up when there is no data flowing into the computer but I could not figure out why. All the cables are correctly wired so I think that the problem is in the software itself. The software also highlight the Honeywell read-out box part on the block diagram to show where the error is.

I am attaching my error message screenshot and my block diagram. The red circle is where the Honeywell read-out box part is and it is where the error message highlights.

Please I am a little desperate here and need all the help that I can get.

Thank you!!!

[StevenD]

Your message makes no sense. First off the part number you give (060-1833-18) is for a transducer, not a "read-out box", secondly I only see analog options for that transducer and the image of LabVIEW code (not actual code) you posted looks like you are trying to read serial data. 

I Googled "SC500" and I found a page that refers to a Honeywell signal conditioner. I am guessing that is what you are calling a "read-out box?" In any case the only information on any kind of digital communication I could find there is something called Honeywell's Signature Calibration. Even if you could read that with a serial port (which I doubt you can) that information only contains calibration data and doesn't have the signal, IE pressure in it. Just the instructions on how to interpret the analog signal. 

[seb_Dai]

Hi, StevenD:

Sorry about the mistake. The part number for the read-out box is 060-J500-10.

[StevenD · Accepted solution]

Ahhhh.. Ok I stand corrected, it looks like that box does have 232 or 485 communication port. Have you taken a look at this document from Honeywell? What steps have you taken so far to try and communicate with the device? Section 6 of the linked document describes using Hyperterminal to communicate with the device. I don't think Hyperterminal ships with newer versions of Windows, but you can use a similar program (I am a fan of Termite ) and the steps should be similar enough that you should be able to do direct communication. That's where I would start.

[seb_Dai]

Hi, StevenD

Thank you for your message. I looked at the section 6 of the link you send me and followed the instruction on using HyperTerminal to communicate with the device and here is what I observed.

I have two pressure read-out boxes connected to the computer and I am using a usb-to-serial port adapter to connect one of them because there is only one serial port on the computer. The other one read-out box is a MKS read-out box (part number: PDR2000AO). Based on the device manager (screenshot attached), the serial port on the computer is COM1 and the other one where the adapter is plugged in is COM3. At first the Honeywell box is connected to the COM1 and MKS is connected to the COM3. I used HyperTerminal and I was able to communicate with COM1 but failed with COM3.

I then swapped these two connections and make MKS connected to COM1 and Honeywell connected to COM3. The result is that I failed to communicate with COM1 but I was able to communicate with COM3.

It seems that what the result is trying to tell me is that Honeywell is working fine but the MKS is not working. However, when I tried to record data using LabVIEW, the pressure reading on the MKS read-out box can actually be transmitted onto the software panel. I am a little confused here and really appreciate it if you could provide further help.

Thanks!

[StevenD]

What do you mean when you say you failed to communicate with COM1 or 3? Was there an error message? Did you change the port settings to match the device? IE baud, parity, stop bits, etc?

[seb_Dai]

Okay sorry i was being a fool. I used the code for Honeywell on the MKS instrument. I will need to check to see if they have the same thing for MKS but right now it seems that both the Honeywell and the MKS are working fine since the MKS reading can be transmitted onto to the computer and the Honeywell can respond through HyperTerminal. I have attached a screenshot of the message I got from Honeywell. It is the same as described in section 6 of the document. But still, it still shows time-out error on the LabVIEW software.

Thanks!

[seb_Dai]

The port settings are the same as those mentioned in section 6 for the Honeywell.

[StevenD]

Well you have verified that you can communicate with the Honeywell so next step would be to debug software. I recommend getting rid of the instrument assist VI's. They are not that great and are probably opening and closing that port unnecessarily. Use VISA configure port (and change the termination character to 13) and the VISA functions. This way you are opening the port once, and closing the port once. I would do this for both serial devices.

Should look something like this:

The command should be something different, I just used the example from the manual. Set your read bytes to be something bigger than you expect to receive (the termination character will ensure the read returns data whenever that character is read). Then parse your response as you are doing in your picture.

Edit - The command should also end in a carriage return, ascii code 13. Right click and change the display to "\ codes display" and add \r at then end.

[seb_Dai]

Okay I was able to make the time-out error disappear and push the run button but instead of showing the reading of the Honeywell read-out box it just shows a constant number of 11.