06-27-2012 01:46 PM
There is an input to the VISA Configure Serial Port called 'Enable Termination Char (T)'. Try wiring a False constant to it. Try sending a \r or \r\n after the T you are writing.
06-27-2012 02:10 PM
so without wiring a False constant but instead of sending T\n string, I sent T\r then it worked! quite strange even though I set LF = ON on the instrument. but anyhow, thank you! Now I can go ahead and try to add some extra stuff to it. I will also need to control a temp chamber using modbus rtu protocol in the same vi....not very easy for me but feel great when it work.
06-27-2012 03:20 PM
Which just goes to show something about the accuracy of some manuals, I guess.
07-02-2012 01:45 PM
Hi Dennis,
I have another instrument that I would like to control using LabView, a Watlow temp controller
http://www.watlow.com/products/controllers/ez-zone-pm-controller.cfm?famid=14
Its communication protocol is Modbus RTU. It appeared that Watlow had a driver for it but it was written for 32-bit OS only and I cannot use it since my OS is 64-bit. So I decided to download NI Modbus library to try to read and write the temp to the controller with no success with timeout error. Do you know any program that is equivalent to puTTy but instead capable of sending Modbus RTU message then receiving and parsing the response? I wanted to check first if I have established comm between the controller and my PC
Thanks a lot
Tim
07-02-2012 01:48 PM
Oh actually there is a program on Watlow's website. Let me check it out first.
07-02-2012 02:53 PM
02-13-2015 02:46 PM
Here is a example of how I use the Fluke 1504 with C++:
http://www.data-acquisition-software.com/rs232-software/
See the comments in the *.h files. There are some notes on configuration settings.
There are 2 perfidious traps that might be waiting for you.
1) The actual thermo probe is "mated" with the internal settings of the Fluke 1504. I belive the most common thermo probe is a 10K type 2. Make sure that the calibration settings are applied to the FLUKE 1504 match the reported probe coefficients for your attached probe. If you do not do this then your reported temperture will not be accurate. Guess how I know about this.(Grrrr)
2) The Fluke 1504 has a behavior that I refer to as "AUTO-SPEW". The Fluke spews the temperature measurements automatically to the RS-232. This behavior creates hideous mischeif when you wait for an RS232 reply to some other command. There is a button press squence that supresses this behavior. When I recieved my Fluke 1504 from the factory, this "feature" was enabled.
If you use Unix, then email me. I made a unix RS232 driver that will work with the Fluke 1504.
If you have troubles, then please use the "contact me" page.
03-20-2015 02:57 PM
Controlling a Watlow is not trivial. Watlow sometimes use a software overlay know as "MODBUS". Ask you customer representative if your controller behaves similar to an "F4" controller. If this is true then please examine the attached zipped file.
You will need to configure some of the attributes (controller number, RS232 BAUD rate) from button pokes on the front panel before you use ANY controller software.
Also, the actual temperture that the Watlow reports is only accurate at the very tip internal sensor. This internal sensor resembles a dangling wire inside ot the thermal chamber. If you need precise (<0.1C) temperture measurements, then use the FLUKE 1504! If your DUT has an enclosure, then you might need to expose the temperture senstive portions. Place the FLUKE 1504 as close as possible to the temperture sensitive portions of your DUT.
If you have trouble with what I have attached, then contact me via the "contact" page of my web page:
03-20-2015 02:57 PM
Controlling a Watlow is not trivial. Watlow sometimes use a software overlay know as "MODBUS". Ask you customer representative if your controller behaves similar to an "F4" controller. If this is true then please examine the attached zipped file.
You will need to configure some of the attributes (controller number, RS232 BAUD rate) from button pokes on the front panel before you use ANY controller software.
Also, the actual temperture that the Watlow reports is only accurate at the very tip internal sensor. This internal sensor resembles a dangling wire inside ot the thermal chamber. If you need precise (<0.1C) temperture measurements, then use the FLUKE 1504! If your DUT has an enclosure, then you might need to expose the temperture senstive portions. Place the FLUKE 1504 as close as possible to the temperture sensitive portions of your DUT.
If you have trouble with what I have attached, then contact me via the "contact" page of my web page: