Watlow F4 and Modbus

[unclebump]

try this website <a href="http://www.watlow.com/literature/pti_search.cfm" target="_blank">http://www.watlow.com/literature/pti_search.cfm</a>&nbsp;and search 'watlow controls data communications'. You should get three manuals that explain the modbus communication.
what is the full part number of the instrument?? What modbus register value are you trying to read?? A single register or multiple registers?? What modbus function code are you using?? Are you sending the address as 40100 or just 100. You may even need to add one to the register value. Use portmon to snoop the communication. Is it using RS232 or RS485??

[Jason Hobbs]

I just want to make sure you guys are aware of the certified LabVIEW instrument driver on IDNet (ni.com/idnet) for the Watlow F4 Series:
<a href="https://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=E3B19B3E9722659CE034080020E74861" target="_blank">https://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=E3B19B3E9722659CE034080020E74861</a>

[Brian Beal]

Joe-
Sorry that I just thought of this now.&nbsp; You could download Watlow's configuration software.&nbsp; I think it is called Watview.&nbsp; It is a free download, and this will certainly work if there are no hardware problems.

[sigaman]

Joe,
Did you get anywhere with your timeout issues communicating with the F4?&nbsp; I am having the same problems and was wondering if you had any ideas.
Thanks,
&nbsp;
-Steve
&nbsp;

[sigaman]

I just wanted to let you guys know, I was having problems communicating with the F4, then I did a firmware update and all works well now.&nbsp; The firmware update is on Watlow's website so you might want to try that if you are not on the current firmware.
Good Luck,
-Steve

[dandnguy]

Hi Joe,
I have just bought a Watlow F4 controller and it is not responding to the query as well.
I just want to read the current temperature (Register 100 - Input 1 Value).
I have also tried to read other simple register like current date, month, etc... but it is not returning anything.
Did you find out what is wrong? If so, can you tell me what was wrong?
Thanks
Dan

[jonwilson]

Hi Peter,
Thanks for the quick response.
Yes my PC com setting is the same as the F4 Controller. I was able to change the controller temperature unit from F to C or vice versa.
But I was unable to read anything from any of the holding registers.
Please advise.
Thanks
Dan

[falkpl]

I had a heck of a time getting the watlows to communicate with the PC using both the modbus libraries and writing my own visa commands.&nbsp; I dod get it to work though (It was my first attempt at modbus).&nbsp; The main culprit was the baud rate.&nbsp; The client insisted that they had set it to 9600 and the manual did state that the modbus is to be set to 9600 but it was 19200.&nbsp; Once the settings were correct I had little problem using visa to communicate with the watlow using my own string parser and simple visa com writes and reads.&nbsp; Dont give up, start simple and pass the example strings (make sure you are in hex string mode) and see if you can get a valid response.&nbsp; Good luck.
&nbsp;
Paul