Has anyone written for a Honeywell UMC800 with Modbus?

[Meinesz]

Honeywell UMC800 is connected to the PC via a RS232/RS485 converter

[Khalid]

Hi Meinesz,

If your device communicates using the Modbus protocol, you basically need some Modbus VIs/drivers/Servers to communicate with it from LabVIEW.

There are several options for communicating to Modbus devices from LabVIEW:

1. Write your own driver

Modbus is a simple protocol so you can write a driver, or part of it that you need in LabVIEW. You'll use serial/VISA as with any other serial driver (note that there's a Modbus-TCP protocol as well). The protocol specification below should give you an idea of what's involved. In addition, C/C++ and VisualBasic APIs are also available.

The Modbus protocol can be found here:
http://www.modicon.com/techpubs/toc7.html

Modbus-IDA now maintains it:
http://www.modbus.org

2. Use existing LabVIEW VIs

There are several VIs available out there (none from NI though; some are from Alliance members). Some of these are free:

http://www.air.nl/nlibrary/modbus_vi.html

http://www.users.globalnet.co.uk/~pseudo/downloads.html
(see Eurotherm; uses Modbus)

http://www.softwarewithrelish.com/specs/BusVIEW.html

http://www.ewebsite.nl/eng/html/modbus.html

http://www.saphir.fr/FR/produits/pilotes/modbus/index.htm

http://labview.citeng.com/pagesEN/products/modbus.aspx

Etc...

3. Use an OPC Server

As Modbus is heavily used in Industrial Automation, there are several OPC Servers available for it, including one from NI:

http://ni.com/opc/opcservers.htm

Here you'll find a free one from Matrikon:
http://www.matrikon.com/drivers/FreeDownloads.asp

In LabVIEW, as you very likely know, to talk to an OPC Server, you would either use DataSocket, or use the DSC module which has built-in support for OPC, and is recommended over DataSocket especially when you have a bunch of IO points.

4. Use an ActiveX Server

There are ActiveX Servers available which talk Modbus.

http://www.automatedsolutions.com/products/modbusrtu.asp

A Google search returns a bunch for these.

You will have to know what Modbus registers map to what "items" in your device. These will have "addresses" which the documentation should provide.

Hope this gets you started.

Regards,

Khalid

[Meinesz]

Thanks you for the information, it's very usefull

[Khalid]

I just wanted to add this to the above list of VIs for Modbus:  NI's Modbus Library.

-Khalid

[Khalid]

Here's the NI-Modbus library without the MSI installer and saved back for LabVIEW 6.1:  MGI Modbus

-Khalid

[Khalid]

Here's the 7.1.1 version.

[Khalid]

And the 8.20 version...

[Nishant]

Dear Khalid,

      Please guide me to get the drivers for the Modbus TCP/IP, please give me the path for the modbus TCP/IP driver.

Thanks,

Nishant

[unclebump]

Try here.

https://forums.ni.com/t5/Reference-Design-Content/LabVIEW-Modbus-API/ta-p/3524019