will not recognize pH meter

[agorden]

I have two setups with Labview. Each runs a autoburet, a pH meter, and a UV-Vis spectrophotometer. On one, every now and again when you use the spectrophotmeter the pH meter gets "stuck" and will only read 0mv. This can usually be corrected by turning the program off and then back on. This is annoying but not critical. On the second setup, labview will no longer recognize the pH meter at all, always reading 0mv although the pH meter by itself works.
Any ideas?

[JoshuaP]

Hey Agorden,

You didn't mention how you are communicating to your instruments, but I am assuming you are using GPIB or serial. If so, the first place to check is with NI-SPY. This will let you know what is being communicated in the back ground. You should be able to see with NI-SPY whether or not you instrument is transmitting the correct data, or if your program is parsing the data correctly.

Here is a link to more information about NI-SPY.
http://zone.ni.com/devzone/conceptd.nsf/webmain/C31BC5FB34DBC0EF86256ADF007B8A47?opendocument
http://www.ni.com/support/vxi/spy/spy.htm

Just open up NI-SPY and run it while your program is running. You should be able to see all data that is being read and be able to see if it is changing.

I hope this helps ou
t.

JoshuaP
National Instruments