Want to Control a Blower, But No Experience w/Modbus


Thread Starter


I have a Delta VFD-L that I use to control a blower on my coffee roaster. In conjunction, I use a piece of software called Artisan to log the temperature probe readings. Artisan can also control Modbus devices. Given the Delta VFD-L allows for Modbus control, I'd love to get that setup so I can control the blower via the software. The problem is I have no experience with Modbus and its quite difficult for me to understand when I read the documentation.

I'm looking for a kind soul who might be able to help me out.

Bob Peterson

There is no trick that anyone can give you. You will need to read the vfd manual to figure out what Modbus address(es) need to be changed to control the vfd.

Typically your computer will have a serial port that will be used to communicate with the drive. You will have to configure your software to use the serial port.

You will also have to configure the vfd to accept commands from my bus as opposed to terminals on the hardwired interface and to give the vfd a Modbus address.
As you mentioned you want to read Modbus data of Delta VFD-L in Artisan software. I gone through Delta VFD-L User Manual document and found that Delta VFD-L supports Modbus ASCII. Please check what is there in your site. So your software should support Modbus ASCII. If not, then you have to use some convertor. From User manual of Delta VFD-L all data is in Holding registers and some is only read and some are read and write. So basically you have to use Function code 03 for reading holding registers and 06 for writing holding registers. The address of VFD to be set which in manual mentioned that address can be set from 1 to 63 as it uses DIP switches 1 to 6. Please check what is there in your site.

Hope this may be helpful.



If you want to build a control application quickly for your blower, why don't you try Daacoworks's Modbus programming Interface?

Daacoworks's Modern Modbus API library is available in two languages (Java and .NET)

It's lean & event-driven architecture simplifies Modbus communication interface for the developers.

checkout www.daacoworks.com