Problem with writing to Eurotherm 2416 controller - Keep getting Timeout error

[CaptainPuma]

I'm designing a LabVIEW-application for controlling the heating of a furnace, using the Eurotherm 2416 controller, but I keep bumping into errors.

First of all, I have established communication using the Eurotherm Sampler and iTools OPC-server. I am able to read values, and write SOME values like Proportional Band and alarm setpoints, but strangely enough I'm not able to write values such as Setpoint and Integration Time. Odd.

Secondly, I downloaded the 24xx drivers, v3.06 for LabVIEW from NI. Using the provided examples, I tried some simple read/write operations. Now, every single time I try to write a value to the controller, ANY value, I recieve the  -1073807339 Timeout error.
After some troubleshooting I'm still in the dark as to where the error lies. It's probably not the wiring or in the controller, though, so it's probably the LabVIEW program.
Do anyone here have experience in using this set of drivers with this controller? Any known issues with the drivers?

Any help will be appreciated

[Brian_Beal]

I have not used that driver, but have used a more generic Modbus driver.  I had no problems, but I was only reading process value and changing setpoint on a 2404.  If you have the open version of iTools, I would just use the Eurotherm OPC server instead of Modbus with Labview.  That should be very simple, and I have used Labview and the OPC server that way without any problems.

[jjp377]

The et24xx driver uses VISA to communicate.  Error -1073807339 is a VISA timeout error.  Since you are using Eurotherm software to establish communication.  Do you know if the Eurotherm software uses VISA as well?  Could you test commands like ID query  *IDN?using VISA communication in Measurement & Automation Explorer.  Do you have updated versions of the NI-VISA software? 

[Jiri_Kominek]

It looks like driver didn't initialize. Please check settings of serial port parameters with parameters set in the instrument. There's no automatic find featrue in the driver, you have to set it manually. Parameters including Unit address can be found in et24xx Initialize.vi and in examples serial interface parameters are as cluster constant in diagram (bottom left corner).

[ChillyWilly]

Perhaps you have already resolved your problem and if you have I'll be interested in finding out what the issue was.  I was getting the same error message using the eurotehrm drivers and all the software settings matched the hardware communication settings.  I found that the instrument I am trying to control (a three zone furnace) was wired (serial comm cables) with the Tx and Rx wires switched so a straigth serial cable will not work.  In my case I can either get a null modem adapter or just get inside the control box and switch the Tx and Rx wires so that I can use a straigth through serial cable.

If you have not fixed your problem I hope this helps you.

P.S. Be careful with the examples that come with the drivers; one of them re-configures the controller and may not behave as you expect if you have already mannually configured it.

[CaptainPuma]

The problem was resolved, and to be honest, it was embarrasingly simple.

It's been over a year now, so I can't really recall the specifics but the "Write to Eurotherm" VIs came with a floating point version in addition to the regular one. It was just a question of switching between the two, I can't remember which version worked.

Thank you for your help! 

[BZajec]

Dear CaptainPuma,

I know it has been a long time since you were debugging this probem. I have more basic problem: I can't establish ANY connection between my PC (using LV 7.1 with et24xx library) and my Eurotherm 2416. I am getting VISA timeout error. I guess I have the right cable (for rs232) since I can easily communicate using e.g. iTools.

Can you please tell me what should be the settings in the Eurotherm 2416 and what should be set in ET24XX Initialize.vi  that comes with et24xx library ?

regards,

 Bojan

[Song_M]

Hey BZajec!

The first step we should take is make sure we can communicate with the device in hyperterminal.  Try to use some simple commands that comes with the manual, and make sure that the communication is established!  Thanks!

[Brian_Beal]

The 2416 usually uses Modbus to communicate.  I believe it can also use EI-bysinc.  Neither one are straight ASCII, so Hyperterminal will not work.

[ChillyWilly]

Here is a very simple read and write program that you can check your communications to the controller with.

You have to make sure that the HA menu in the controller (refer to the manual, section 6-11) is set to:

Func = mod

Baud = 9600

Prty = EvEn

or change the numbers in the program to reflect the settings in you controller.

The other setting in you controller that you need to match is the unit address.  I've found that in the units I've had to program for this is usually set to 11, but if that does not work for your unit and everything else matches then play with this number in the program, start at 0 and then work all the way to up.  This may take time as you could go up to 99.

I hope this helps out.