How to control velocity with frequency inverter cfw08?

[luucas]

Hi everyone,

I would like to set the electric motor velocity using the labview, I have a frequency inverter cfw 08 to control motor, do you have any examples to send me?, i don't know if it is need to use Modbus.

Tks

[FloresFe]

Hey Luccas,

Firstly, I strongly recommend you to give more details on your question, like it is not everyone who knows the CFW 08 frequency inverter, so it would help a lot to post a link to its manual.

I'm not really into Frequency Inverters but from what I learned, you can use different industrial protocols (e.g. ModBUS) or simply use a PWM signal to control de speed. What you are going to implement will depend on what is more suited for your application. So, to get to know more about it and give you a better help, here are some questions:

1) What is the hardware interface you are implementing to communicate with the CFW08? Is that an NI Board, PLC, uC?

2) What is the purpose of your application, I mean, what are you trying to do?

3) Have you tried googling "LabVIEW CFW 08"? I did and I found some paperworks on it (in portuguese). Give it a shot!

Best Regards

[luucas]

Hey Felipe.

I'm trying to control the electric motor's velocity , using labview. The motor is part of a fan, which makes the air flow in an wind tunnel. The frequency inverter is the wind tunnnel HMI, and I want to replace it with labview, but the only way to control the motor is through the frequency inverter. I googled it, but I've only found how to track the engine status with labview. I want to control the motor RPM because I want to control the tunnel air flow. In the manual it says  the frequency inverter can communicate with external devices using the serial RS-485 through modbus. To summarize it, I want labview to act like the master and the frequency inverter to act as slave where I set a RPM in labview, and then labview sets it in the frequency inverter.

Best Regards

[FloresFe]

Hi Luccas,

Thanks for making it clearer!

As of page 188, the manual describes the communication via ModBus RTU. From what I read, most part of that LabVIEW already implements, except for the specific adresses/variables the CFW 08 uses. So for that, it would be good to take a look at the different ways you can create VIs in LabVIEW to communicate using ModBUS.

Check out this link! Try running the suggested examples so you can better understand how they work.

Once you decide which is the Software approach you're going to use, you should have an RS-485 interface to connect your computer to the Frequency Inverter. Does your computer have an RS-485 port or do you have an adapter?

Best Regards